From ed79165d195c99e5d8e283bb5bbf84c3363ae254 Mon Sep 17 00:00:00 2001 From: Maksymilian Osowski Date: Mon, 26 Jul 2010 17:00:30 +0100 Subject: Added the sources. Change-Id: Ifd46f7bc83306f9e16ec2a725c2300f584068e59 --- name/fraser/neil/plaintext/diff_match_patch.java | 2428 ++++++++++++++++++++ .../neil/plaintext/diff_match_patch_test.java | 945 ++++++++ 2 files changed, 3373 insertions(+) create mode 100644 name/fraser/neil/plaintext/diff_match_patch.java create mode 100644 name/fraser/neil/plaintext/diff_match_patch_test.java diff --git a/name/fraser/neil/plaintext/diff_match_patch.java b/name/fraser/neil/plaintext/diff_match_patch.java new file mode 100644 index 0000000..92e65e4 --- /dev/null +++ b/name/fraser/neil/plaintext/diff_match_patch.java @@ -0,0 +1,2428 @@ +/* + * Diff Match and Patch + * + * Copyright 2006 Google Inc. + * http://code.google.com/p/google-diff-match-patch/ + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package name.fraser.neil.plaintext; + +import java.io.UnsupportedEncodingException; +import java.net.URLEncoder; +import java.net.URLDecoder; +import java.util.ArrayList; +import java.util.Arrays; +import java.util.HashMap; +import java.util.HashSet; +import java.util.LinkedList; +import java.util.List; +import java.util.ListIterator; +import java.util.Map; +import java.util.Set; +import java.util.Stack; +import java.util.regex.Matcher; +import java.util.regex.Pattern; + + +/* + * Functions for diff, match and patch. + * Computes the difference between two texts to create a patch. + * Applies the patch onto another text, allowing for errors. + * + * @author fraser@google.com (Neil Fraser) + */ + +/** + * Class containing the diff, match and patch methods. + * Also contains the behaviour settings. + */ +public class diff_match_patch { + + // Defaults. + // Set these on your diff_match_patch instance to override the defaults. + + /** + * Number of seconds to map a diff before giving up (0 for infinity). + */ + public float Diff_Timeout = 1.0f; + /** + * Cost of an empty edit operation in terms of edit characters. + */ + public short Diff_EditCost = 4; + /** + * The size beyond which the double-ended diff activates. + * Double-ending is twice as fast, but less accurate. + */ + public short Diff_DualThreshold = 32; + /** + * At what point is no match declared (0.0 = perfection, 1.0 = very loose). + */ + public float Match_Threshold = 0.5f; + /** + * How far to search for a match (0 = exact location, 1000+ = broad match). + * A match this many characters away from the expected location will add + * 1.0 to the score (0.0 is a perfect match). + */ + public int Match_Distance = 1000; + /** + * When deleting a large block of text (over ~64 characters), how close does + * the contents have to match the expected contents. (0.0 = perfection, + * 1.0 = very loose). Note that Match_Threshold controls how closely the + * end points of a delete need to match. + */ + public float Patch_DeleteThreshold = 0.5f; + /** + * Chunk size for context length. + */ + public short Patch_Margin = 4; + + /** + * The number of bits in an int. + */ + private int Match_MaxBits = 32; + + /** + * Internal class for returning results from diff_linesToChars(). + * Other less paranoid languages just use a three-element array. + */ + protected static class LinesToCharsResult { + protected String chars1; + protected String chars2; + protected List lineArray; + + protected LinesToCharsResult(String chars1, String chars2, + List lineArray) { + this.chars1 = chars1; + this.chars2 = chars2; + this.lineArray = lineArray; + } + } + + + // DIFF FUNCTIONS + + + /** + * The data structure representing a diff is a Linked list of Diff objects: + * {Diff(Operation.DELETE, "Hello"), Diff(Operation.INSERT, "Goodbye"), + * Diff(Operation.EQUAL, " world.")} + * which means: delete "Hello", add "Goodbye" and keep " world." + */ + public enum Operation { + DELETE, INSERT, EQUAL + } + + + /** + * Find the differences between two texts. + * Run a faster slightly less optimal diff + * This method allows the 'checklines' of diff_main() to be optional. + * Most of the time checklines is wanted, so default to true. + * @param text1 Old string to be diffed. + * @param text2 New string to be diffed. + * @return Linked List of Diff objects. + */ + public LinkedList diff_main(String text1, String text2) { + return diff_main(text1, text2, true); + } + + /** + * Find the differences between two texts. Simplifies the problem by + * stripping any common prefix or suffix off the texts before diffing. + * @param text1 Old string to be diffed. + * @param text2 New string to be diffed. + * @param checklines Speedup flag. If false, then don't run a + * line-level diff first to identify the changed areas. + * If true, then run a faster slightly less optimal diff + * @return Linked List of Diff objects. + */ + public LinkedList diff_main(String text1, String text2, + boolean checklines) { + // Check for null inputs. + if (text1 == null || text2 == null) { + throw new IllegalArgumentException("Null inputs. (diff_main)"); + } + + // Check for equality (speedup). + LinkedList diffs; + if (text1.equals(text2)) { + diffs = new LinkedList(); + diffs.add(new Diff(Operation.EQUAL, text1)); + return diffs; + } + + // Trim off common prefix (speedup). + int commonlength = diff_commonPrefix(text1, text2); + String commonprefix = text1.substring(0, commonlength); + text1 = text1.substring(commonlength); + text2 = text2.substring(commonlength); + + // Trim off common suffix (speedup). + commonlength = diff_commonSuffix(text1, text2); + String commonsuffix = text1.substring(text1.length() - commonlength); + text1 = text1.substring(0, text1.length() - commonlength); + text2 = text2.substring(0, text2.length() - commonlength); + + // Compute the diff on the middle block. + diffs = diff_compute(text1, text2, checklines); + + // Restore the prefix and suffix. + if (commonprefix.length() != 0) { + diffs.addFirst(new Diff(Operation.EQUAL, commonprefix)); + } + if (commonsuffix.length() != 0) { + diffs.addLast(new Diff(Operation.EQUAL, commonsuffix)); + } + + diff_cleanupMerge(diffs); + return diffs; + } + + + /** + * Find the differences between two texts. Assumes that the texts do not + * have any common prefix or suffix. + * @param text1 Old string to be diffed. + * @param text2 New string to be diffed. + * @param checklines Speedup flag. If false, then don't run a + * line-level diff first to identify the changed areas. + * If true, then run a faster slightly less optimal diff + * @return Linked List of Diff objects. + */ + protected LinkedList diff_compute(String text1, String text2, + boolean checklines) { + LinkedList diffs = new LinkedList(); + + if (text1.length() == 0) { + // Just add some text (speedup). + diffs.add(new Diff(Operation.INSERT, text2)); + return diffs; + } + + if (text2.length() == 0) { + // Just delete some text (speedup). + diffs.add(new Diff(Operation.DELETE, text1)); + return diffs; + } + + String longtext = text1.length() > text2.length() ? text1 : text2; + String shorttext = text1.length() > text2.length() ? text2 : text1; + int i = longtext.indexOf(shorttext); + if (i != -1) { + // Shorter text is inside the longer text (speedup). + Operation op = (text1.length() > text2.length()) ? + Operation.DELETE : Operation.INSERT; + diffs.add(new Diff(op, longtext.substring(0, i))); + diffs.add(new Diff(Operation.EQUAL, shorttext)); + diffs.add(new Diff(op, longtext.substring(i + shorttext.length()))); + return diffs; + } + longtext = shorttext = null; // Garbage collect. + + // Check to see if the problem can be split in two. + String[] hm = diff_halfMatch(text1, text2); + if (hm != null) { + // A half-match was found, sort out the return data. + String text1_a = hm[0]; + String text1_b = hm[1]; + String text2_a = hm[2]; + String text2_b = hm[3]; + String mid_common = hm[4]; + // Send both pairs off for separate processing. + LinkedList diffs_a = diff_main(text1_a, text2_a, checklines); + LinkedList diffs_b = diff_main(text1_b, text2_b, checklines); + // Merge the results. + diffs = diffs_a; + diffs.add(new Diff(Operation.EQUAL, mid_common)); + diffs.addAll(diffs_b); + return diffs; + } + + // Perform a real diff. + if (checklines && (text1.length() < 100 || text2.length() < 100)) { + checklines = false; // Too trivial for the overhead. + } + List linearray = null; + if (checklines) { + // Scan the text on a line-by-line basis first. + LinesToCharsResult b = diff_linesToChars(text1, text2); + text1 = b.chars1; + text2 = b.chars2; + linearray = b.lineArray; + } + + diffs = diff_map(text1, text2); + if (diffs == null) { + // No acceptable result. + diffs = new LinkedList(); + diffs.add(new Diff(Operation.DELETE, text1)); + diffs.add(new Diff(Operation.INSERT, text2)); + } + + if (checklines) { + // Convert the diff back to original text. + diff_charsToLines(diffs, linearray); + // Eliminate freak matches (e.g. blank lines) + diff_cleanupSemantic(diffs); + + // Rediff any replacement blocks, this time character-by-character. + // Add a dummy entry at the end. + diffs.add(new Diff(Operation.EQUAL, "")); + int count_delete = 0; + int count_insert = 0; + String text_delete = ""; + String text_insert = ""; + ListIterator pointer = diffs.listIterator(); + Diff thisDiff = pointer.next(); + while (thisDiff != null) { + switch (thisDiff.operation) { + case INSERT: + count_insert++; + text_insert += thisDiff.text; + break; + case DELETE: + count_delete++; + text_delete += thisDiff.text; + break; + case EQUAL: + // Upon reaching an equality, check for prior redundancies. + if (count_delete >= 1 && count_insert >= 1) { + // Delete the offending records and add the merged ones. + pointer.previous(); + for (int j = 0; j < count_delete + count_insert; j++) { + pointer.previous(); + pointer.remove(); + } + for (Diff newDiff : diff_main(text_delete, text_insert, false)) { + pointer.add(newDiff); + } + } + count_insert = 0; + count_delete = 0; + text_delete = ""; + text_insert = ""; + break; + } + thisDiff = pointer.hasNext() ? pointer.next() : null; + } + diffs.removeLast(); // Remove the dummy entry at the end. + } + return diffs; + } + + + /** + * Split two texts into a list of strings. Reduce the texts to a string of + * hashes where each Unicode character represents one line. + * @param text1 First string. + * @param text2 Second string. + * @return An object containing the encoded text1, the encoded text2 and + * the List of unique strings. The zeroth element of the List of + * unique strings is intentionally blank. + */ + protected LinesToCharsResult diff_linesToChars(String text1, String text2) { + List lineArray = new ArrayList(); + Map lineHash = new HashMap(); + // e.g. linearray[4] == "Hello\n" + // e.g. linehash.get("Hello\n") == 4 + + // "\x00" is a valid character, but various debuggers don't like it. + // So we'll insert a junk entry to avoid generating a null character. + lineArray.add(""); + + String chars1 = diff_linesToCharsMunge(text1, lineArray, lineHash); + String chars2 = diff_linesToCharsMunge(text2, lineArray, lineHash); + return new LinesToCharsResult(chars1, chars2, lineArray); + } + + + /** + * Split a text into a list of strings. Reduce the texts to a string of + * hashes where each Unicode character represents one line. + * @param text String to encode. + * @param lineArray List of unique strings. + * @param lineHash Map of strings to indices. + * @return Encoded string. + */ + private String diff_linesToCharsMunge(String text, List lineArray, + Map lineHash) { + int lineStart = 0; + int lineEnd = -1; + String line; + StringBuilder chars = new StringBuilder(); + // Walk the text, pulling out a substring for each line. + // text.split('\n') would would temporarily double our memory footprint. + // Modifying text would create many large strings to garbage collect. + while (lineEnd < text.length() - 1) { + lineEnd = text.indexOf('\n', lineStart); + if (lineEnd == -1) { + lineEnd = text.length() - 1; + } + line = text.substring(lineStart, lineEnd + 1); + lineStart = lineEnd + 1; + + if (lineHash.containsKey(line)) { + chars.append(String.valueOf((char) (int) lineHash.get(line))); + } else { + lineArray.add(line); + lineHash.put(line, lineArray.size() - 1); + chars.append(String.valueOf((char) (lineArray.size() - 1))); + } + } + return chars.toString(); + } + + + /** + * Rehydrate the text in a diff from a string of line hashes to real lines of + * text. + * @param diffs LinkedList of Diff objects. + * @param lineArray List of unique strings. + */ + protected void diff_charsToLines(LinkedList diffs, + List lineArray) { + StringBuilder text; + for (Diff diff : diffs) { + text = new StringBuilder(); + for (int y = 0; y < diff.text.length(); y++) { + text.append(lineArray.get(diff.text.charAt(y))); + } + diff.text = text.toString(); + } + } + + + /** + * Explore the intersection points between the two texts. + * @param text1 Old string to be diffed. + * @param text2 New string to be diffed. + * @return LinkedList of Diff objects or null if no diff available. + */ + protected LinkedList diff_map(String text1, String text2) { + long ms_end = System.currentTimeMillis() + (long) (Diff_Timeout * 1000); + // Cache the text lengths to prevent multiple calls. + int text1_length = text1.length(); + int text2_length = text2.length(); + int max_d = text1_length + text2_length - 1; + boolean doubleEnd = Diff_DualThreshold * 2 < max_d; + List> v_map1 = new ArrayList>(); + List> v_map2 = new ArrayList>(); + Map v1 = new HashMap(); + Map v2 = new HashMap(); + v1.put(1, 0); + v2.put(1, 0); + int x, y; + Long footstep = 0L; // Used to track overlapping paths. + Map footsteps = new HashMap(); + boolean done = false; + // If the total number of characters is odd, then the front path will + // collide with the reverse path. + boolean front = ((text1_length + text2_length) % 2 == 1); + for (int d = 0; d < max_d; d++) { + // Bail out if timeout reached. + if (Diff_Timeout > 0 && System.currentTimeMillis() > ms_end) { + return null; + } + + // Walk the front path one step. + v_map1.add(new HashSet()); // Adds at index 'd'. + for (int k = -d; k <= d; k += 2) { + if (k == -d || k != d && v1.get(k - 1) < v1.get(k + 1)) { + x = v1.get(k + 1); + } else { + x = v1.get(k - 1) + 1; + } + y = x - k; + if (doubleEnd) { + footstep = diff_footprint(x, y); + if (front && (footsteps.containsKey(footstep))) { + done = true; + } + if (!front) { + footsteps.put(footstep, d); + } + } + while (!done && x < text1_length && y < text2_length + && text1.charAt(x) == text2.charAt(y)) { + x++; + y++; + if (doubleEnd) { + footstep = diff_footprint(x, y); + if (front && (footsteps.containsKey(footstep))) { + done = true; + } + if (!front) { + footsteps.put(footstep, d); + } + } + } + v1.put(k, x); + v_map1.get(d).add(diff_footprint(x, y)); + if (x == text1_length && y == text2_length) { + // Reached the end in single-path mode. + return diff_path1(v_map1, text1, text2); + } else if (done) { + // Front path ran over reverse path. + v_map2 = v_map2.subList(0, footsteps.get(footstep) + 1); + LinkedList a = diff_path1(v_map1, text1.substring(0, x), + text2.substring(0, y)); + a.addAll(diff_path2(v_map2, text1.substring(x), text2.substring(y))); + return a; + } + } + + if (doubleEnd) { + // Walk the reverse path one step. + v_map2.add(new HashSet()); // Adds at index 'd'. + for (int k = -d; k <= d; k += 2) { + if (k == -d || k != d && v2.get(k - 1) < v2.get(k + 1)) { + x = v2.get(k + 1); + } else { + x = v2.get(k - 1) + 1; + } + y = x - k; + footstep = diff_footprint(text1_length - x, text2_length - y); + if (!front && (footsteps.containsKey(footstep))) { + done = true; + } + if (front) { + footsteps.put(footstep, d); + } + while (!done && x < text1_length && y < text2_length + && text1.charAt(text1_length - x - 1) + == text2.charAt(text2_length - y - 1)) { + x++; + y++; + footstep = diff_footprint(text1_length - x, text2_length - y); + if (!front && (footsteps.containsKey(footstep))) { + done = true; + } + if (front) { + footsteps.put(footstep, d); + } + } + v2.put(k, x); + v_map2.get(d).add(diff_footprint(x, y)); + if (done) { + // Reverse path ran over front path. + v_map1 = v_map1.subList(0, footsteps.get(footstep) + 1); + LinkedList a + = diff_path1(v_map1, text1.substring(0, text1_length - x), + text2.substring(0, text2_length - y)); + a.addAll(diff_path2(v_map2, text1.substring(text1_length - x), + text2.substring(text2_length - y))); + return a; + } + } + } + } + // Number of diffs equals number of characters, no commonality at all. + return null; + } + + + /** + * Work from the middle back to the start to determine the path. + * @param v_map List of path sets. + * @param text1 Old string fragment to be diffed. + * @param text2 New string fragment to be diffed. + * @return LinkedList of Diff objects. + */ + protected LinkedList diff_path1(List> v_map, + String text1, String text2) { + LinkedList path = new LinkedList(); + int x = text1.length(); + int y = text2.length(); + Operation last_op = null; + for (int d = v_map.size() - 2; d >= 0; d--) { + while (true) { + if (v_map.get(d).contains(diff_footprint(x - 1, y))) { + x--; + if (last_op == Operation.DELETE) { + path.getFirst().text = text1.charAt(x) + path.getFirst().text; + } else { + path.addFirst(new Diff(Operation.DELETE, + text1.substring(x, x + 1))); + } + last_op = Operation.DELETE; + break; + } else if (v_map.get(d).contains(diff_footprint(x, y - 1))) { + y--; + if (last_op == Operation.INSERT) { + path.getFirst().text = text2.charAt(y) + path.getFirst().text; + } else { + path.addFirst(new Diff(Operation.INSERT, + text2.substring(y, y + 1))); + } + last_op = Operation.INSERT; + break; + } else { + x--; + y--; + assert (text1.charAt(x) == text2.charAt(y)) + : "No diagonal. Can't happen. (diff_path1)"; + if (last_op == Operation.EQUAL) { + path.getFirst().text = text1.charAt(x) + path.getFirst().text; + } else { + path.addFirst(new Diff(Operation.EQUAL, text1.substring(x, x + 1))); + } + last_op = Operation.EQUAL; + } + } + } + return path; + } + + + /** + * Work from the middle back to the end to determine the path. + * @param v_map List of path sets. + * @param text1 Old string fragment to be diffed. + * @param text2 New string fragment to be diffed. + * @return LinkedList of Diff objects. + */ + protected LinkedList diff_path2(List> v_map, + String text1, String text2) { + LinkedList path = new LinkedList(); + int x = text1.length(); + int y = text2.length(); + Operation last_op = null; + for (int d = v_map.size() - 2; d >= 0; d--) { + while (true) { + if (v_map.get(d).contains(diff_footprint(x - 1, y))) { + x--; + if (last_op == Operation.DELETE) { + path.getLast().text += text1.charAt(text1.length() - x - 1); + } else { + path.addLast(new Diff(Operation.DELETE, + text1.substring(text1.length() - x - 1, text1.length() - x))); + } + last_op = Operation.DELETE; + break; + } else if (v_map.get(d).contains(diff_footprint(x, y - 1))) { + y--; + if (last_op == Operation.INSERT) { + path.getLast().text += text2.charAt(text2.length() - y - 1); + } else { + path.addLast(new Diff(Operation.INSERT, + text2.substring(text2.length() - y - 1, text2.length() - y))); + } + last_op = Operation.INSERT; + break; + } else { + x--; + y--; + assert (text1.charAt(text1.length() - x - 1) + == text2.charAt(text2.length() - y - 1)) + : "No diagonal. Can't happen. (diff_path2)"; + if (last_op == Operation.EQUAL) { + path.getLast().text += text1.charAt(text1.length() - x - 1); + } else { + path.addLast(new Diff(Operation.EQUAL, + text1.substring(text1.length() - x - 1, text1.length() - x))); + } + last_op = Operation.EQUAL; + } + } + } + return path; + } + + + /** + * Compute a good hash of two integers. + * @param x First int. + * @param y Second int. + * @return A long made up of both ints. + */ + protected long diff_footprint(int x, int y) { + // The maximum size for a long is 9,223,372,036,854,775,807 + // The maximum size for an int is 2,147,483,647 + // Two ints fit nicely in one long. + long result = x; + result = result << 32; + result += y; + return result; + } + + + /** + * Determine the common prefix of two strings + * @param text1 First string. + * @param text2 Second string. + * @return The number of characters common to the start of each string. + */ + public int diff_commonPrefix(String text1, String text2) { + // Performance analysis: http://neil.fraser.name/news/2007/10/09/ + int n = Math.min(text1.length(), text2.length()); + for (int i = 0; i < n; i++) { + if (text1.charAt(i) != text2.charAt(i)) { + return i; + } + } + return n; + } + + + /** + * Determine the common suffix of two strings + * @param text1 First string. + * @param text2 Second string. + * @return The number of characters common to the end of each string. + */ + public int diff_commonSuffix(String text1, String text2) { + // Performance analysis: http://neil.fraser.name/news/2007/10/09/ + int text1_length = text1.length(); + int text2_length = text2.length(); + int n = Math.min(text1_length, text2_length); + for (int i = 1; i <= n; i++) { + if (text1.charAt(text1_length - i) != text2.charAt(text2_length - i)) { + return i - 1; + } + } + return n; + } + + + /** + * Do the two texts share a substring which is at least half the length of + * the longer text? + * @param text1 First string. + * @param text2 Second string. + * @return Five element String array, containing the prefix of text1, the + * suffix of text1, the prefix of text2, the suffix of text2 and the + * common middle. Or null if there was no match. + */ + protected String[] diff_halfMatch(String text1, String text2) { + String longtext = text1.length() > text2.length() ? text1 : text2; + String shorttext = text1.length() > text2.length() ? text2 : text1; + if (longtext.length() < 10 || shorttext.length() < 1) { + return null; // Pointless. + } + + // First check if the second quarter is the seed for a half-match. + String[] hm1 = diff_halfMatchI(longtext, shorttext, + (longtext.length() + 3) / 4); + // Check again based on the third quarter. + String[] hm2 = diff_halfMatchI(longtext, shorttext, + (longtext.length() + 1) / 2); + String[] hm; + if (hm1 == null && hm2 == null) { + return null; + } else if (hm2 == null) { + hm = hm1; + } else if (hm1 == null) { + hm = hm2; + } else { + // Both matched. Select the longest. + hm = hm1[4].length() > hm2[4].length() ? hm1 : hm2; + } + + // A half-match was found, sort out the return data. + if (text1.length() > text2.length()) { + return hm; + //return new String[]{hm[0], hm[1], hm[2], hm[3], hm[4]}; + } else { + return new String[]{hm[2], hm[3], hm[0], hm[1], hm[4]}; + } + } + + + /** + * Does a substring of shorttext exist within longtext such that the + * substring is at least half the length of longtext? + * @param longtext Longer string. + * @param shorttext Shorter string. + * @param i Start index of quarter length substring within longtext. + * @return Five element String array, containing the prefix of longtext, the + * suffix of longtext, the prefix of shorttext, the suffix of shorttext + * and the common middle. Or null if there was no match. + */ + private String[] diff_halfMatchI(String longtext, String shorttext, int i) { + // Start with a 1/4 length substring at position i as a seed. + String seed = longtext.substring(i, i + longtext.length() / 4); + int j = -1; + String best_common = ""; + String best_longtext_a = "", best_longtext_b = ""; + String best_shorttext_a = "", best_shorttext_b = ""; + while ((j = shorttext.indexOf(seed, j + 1)) != -1) { + int prefixLength = diff_commonPrefix(longtext.substring(i), + shorttext.substring(j)); + int suffixLength = diff_commonSuffix(longtext.substring(0, i), + shorttext.substring(0, j)); + if (best_common.length() < suffixLength + prefixLength) { + best_common = shorttext.substring(j - suffixLength, j) + + shorttext.substring(j, j + prefixLength); + best_longtext_a = longtext.substring(0, i - suffixLength); + best_longtext_b = longtext.substring(i + prefixLength); + best_shorttext_a = shorttext.substring(0, j - suffixLength); + best_shorttext_b = shorttext.substring(j + prefixLength); + } + } + if (best_common.length() >= longtext.length() / 2) { + return new String[]{best_longtext_a, best_longtext_b, + best_shorttext_a, best_shorttext_b, best_common}; + } else { + return null; + } + } + + + /** + * Reduce the number of edits by eliminating semantically trivial equalities. + * @param diffs LinkedList of Diff objects. + */ + public void diff_cleanupSemantic(LinkedList diffs) { + if (diffs.isEmpty()) { + return; + } + boolean changes = false; + Stack equalities = new Stack(); // Stack of qualities. + String lastequality = null; // Always equal to equalities.lastElement().text + ListIterator pointer = diffs.listIterator(); + // Number of characters that changed prior to the equality. + int length_changes1 = 0; + // Number of characters that changed after the equality. + int length_changes2 = 0; + Diff thisDiff = pointer.next(); + while (thisDiff != null) { + if (thisDiff.operation == Operation.EQUAL) { + // equality found + equalities.push(thisDiff); + length_changes1 = length_changes2; + length_changes2 = 0; + lastequality = thisDiff.text; + } else { + // an insertion or deletion + length_changes2 += thisDiff.text.length(); + if (lastequality != null && (lastequality.length() <= length_changes1) + && (lastequality.length() <= length_changes2)) { + //System.out.println("Splitting: '" + lastequality + "'"); + // Walk back to offending equality. + while (thisDiff != equalities.lastElement()) { + thisDiff = pointer.previous(); + } + pointer.next(); + + // Replace equality with a delete. + pointer.set(new Diff(Operation.DELETE, lastequality)); + // Insert a corresponding an insert. + pointer.add(new Diff(Operation.INSERT, lastequality)); + + equalities.pop(); // Throw away the equality we just deleted. + if (!equalities.empty()) { + // Throw away the previous equality (it needs to be reevaluated). + equalities.pop(); + } + if (equalities.empty()) { + // There are no previous equalities, walk back to the start. + while (pointer.hasPrevious()) { + pointer.previous(); + } + } else { + // There is a safe equality we can fall back to. + thisDiff = equalities.lastElement(); + while (thisDiff != pointer.previous()) { + // Intentionally empty loop. + } + } + + length_changes1 = 0; // Reset the counters. + length_changes2 = 0; + lastequality = null; + changes = true; + } + } + thisDiff = pointer.hasNext() ? pointer.next() : null; + } + + if (changes) { + diff_cleanupMerge(diffs); + } + diff_cleanupSemanticLossless(diffs); + } + + + /** + * Look for single edits surrounded on both sides by equalities + * which can be shifted sideways to align the edit to a word boundary. + * e.g: The cat came. -> The cat came. + * @param diffs LinkedList of Diff objects. + */ + public void diff_cleanupSemanticLossless(LinkedList diffs) { + String equality1, edit, equality2; + String commonString; + int commonOffset; + int score, bestScore; + String bestEquality1, bestEdit, bestEquality2; + // Create a new iterator at the start. + ListIterator pointer = diffs.listIterator(); + Diff prevDiff = pointer.hasNext() ? pointer.next() : null; + Diff thisDiff = pointer.hasNext() ? pointer.next() : null; + Diff nextDiff = pointer.hasNext() ? pointer.next() : null; + // Intentionally ignore the first and last element (don't need checking). + while (nextDiff != null) { + if (prevDiff.operation == Operation.EQUAL && + nextDiff.operation == Operation.EQUAL) { + // This is a single edit surrounded by equalities. + equality1 = prevDiff.text; + edit = thisDiff.text; + equality2 = nextDiff.text; + + // First, shift the edit as far left as possible. + commonOffset = diff_commonSuffix(equality1, edit); + if (commonOffset != 0) { + commonString = edit.substring(edit.length() - commonOffset); + equality1 = equality1.substring(0, equality1.length() - commonOffset); + edit = commonString + edit.substring(0, edit.length() - commonOffset); + equality2 = commonString + equality2; + } + + // Second, step character by character right, looking for the best fit. + bestEquality1 = equality1; + bestEdit = edit; + bestEquality2 = equality2; + bestScore = diff_cleanupSemanticScore(equality1, edit) + + diff_cleanupSemanticScore(edit, equality2); + while (edit.length() != 0 && equality2.length() != 0 + && edit.charAt(0) == equality2.charAt(0)) { + equality1 += edit.charAt(0); + edit = edit.substring(1) + equality2.charAt(0); + equality2 = equality2.substring(1); + score = diff_cleanupSemanticScore(equality1, edit) + + diff_cleanupSemanticScore(edit, equality2); + // The >= encourages trailing rather than leading whitespace on edits. + if (score >= bestScore) { + bestScore = score; + bestEquality1 = equality1; + bestEdit = edit; + bestEquality2 = equality2; + } + } + + if (!prevDiff.text.equals(bestEquality1)) { + // We have an improvement, save it back to the diff. + if (bestEquality1.length() != 0) { + prevDiff.text = bestEquality1; + } else { + pointer.previous(); // Walk past nextDiff. + pointer.previous(); // Walk past thisDiff. + pointer.previous(); // Walk past prevDiff. + pointer.remove(); // Delete prevDiff. + pointer.next(); // Walk past thisDiff. + pointer.next(); // Walk past nextDiff. + } + thisDiff.text = bestEdit; + if (bestEquality2.length() != 0) { + nextDiff.text = bestEquality2; + } else { + pointer.remove(); // Delete nextDiff. + nextDiff = thisDiff; + thisDiff = prevDiff; + } + } + } + prevDiff = thisDiff; + thisDiff = nextDiff; + nextDiff = pointer.hasNext() ? pointer.next() : null; + } + } + + + /** + * Given two strings, compute a score representing whether the internal + * boundary falls on logical boundaries. + * Scores range from 5 (best) to 0 (worst). + * @param one First string. + * @param two Second string. + * @return The score. + */ + private int diff_cleanupSemanticScore(String one, String two) { + if (one.length() == 0 || two.length() == 0) { + // Edges are the best. + return 5; + } + + // Each port of this function behaves slightly differently due to + // subtle differences in each language's definition of things like + // 'whitespace'. Since this function's purpose is largely cosmetic, + // the choice has been made to use each language's native features + // rather than force total conformity. + int score = 0; + // One point for non-alphanumeric. + if (!Character.isLetterOrDigit(one.charAt(one.length() - 1)) + || !Character.isLetterOrDigit(two.charAt(0))) { + score++; + // Two points for whitespace. + if (Character.isWhitespace(one.charAt(one.length() - 1)) + || Character.isWhitespace(two.charAt(0))) { + score++; + // Three points for line breaks. + if (Character.getType(one.charAt(one.length() - 1)) == Character.CONTROL + || Character.getType(two.charAt(0)) == Character.CONTROL) { + score++; + // Four points for blank lines. + if (BLANKLINEEND.matcher(one).find() + || BLANKLINESTART.matcher(two).find()) { + score++; + } + } + } + } + return score; + } + + + private Pattern BLANKLINEEND + = Pattern.compile("\\n\\r?\\n\\Z", Pattern.DOTALL); + private Pattern BLANKLINESTART + = Pattern.compile("\\A\\r?\\n\\r?\\n", Pattern.DOTALL); + + + /** + * Reduce the number of edits by eliminating operationally trivial equalities. + * @param diffs LinkedList of Diff objects. + */ + public void diff_cleanupEfficiency(LinkedList diffs) { + if (diffs.isEmpty()) { + return; + } + boolean changes = false; + Stack equalities = new Stack(); // Stack of equalities. + String lastequality = null; // Always equal to equalities.lastElement().text + ListIterator pointer = diffs.listIterator(); + // Is there an insertion operation before the last equality. + boolean pre_ins = false; + // Is there a deletion operation before the last equality. + boolean pre_del = false; + // Is there an insertion operation after the last equality. + boolean post_ins = false; + // Is there a deletion operation after the last equality. + boolean post_del = false; + Diff thisDiff = pointer.next(); + Diff safeDiff = thisDiff; // The last Diff that is known to be unsplitable. + while (thisDiff != null) { + if (thisDiff.operation == Operation.EQUAL) { + // equality found + if (thisDiff.text.length() < Diff_EditCost && (post_ins || post_del)) { + // Candidate found. + equalities.push(thisDiff); + pre_ins = post_ins; + pre_del = post_del; + lastequality = thisDiff.text; + } else { + // Not a candidate, and can never become one. + equalities.clear(); + lastequality = null; + safeDiff = thisDiff; + } + post_ins = post_del = false; + } else { + // an insertion or deletion + if (thisDiff.operation == Operation.DELETE) { + post_del = true; + } else { + post_ins = true; + } + /* + * Five types to be split: + * ABXYCD + * AXCD + * ABXC + * AXCD + * ABXC + */ + if (lastequality != null + && ((pre_ins && pre_del && post_ins && post_del) + || ((lastequality.length() < Diff_EditCost / 2) + && ((pre_ins ? 1 : 0) + (pre_del ? 1 : 0) + + (post_ins ? 1 : 0) + (post_del ? 1 : 0)) == 3))) { + //System.out.println("Splitting: '" + lastequality + "'"); + // Walk back to offending equality. + while (thisDiff != equalities.lastElement()) { + thisDiff = pointer.previous(); + } + pointer.next(); + + // Replace equality with a delete. + pointer.set(new Diff(Operation.DELETE, lastequality)); + // Insert a corresponding an insert. + pointer.add(thisDiff = new Diff(Operation.INSERT, lastequality)); + + equalities.pop(); // Throw away the equality we just deleted. + lastequality = null; + if (pre_ins && pre_del) { + // No changes made which could affect previous entry, keep going. + post_ins = post_del = true; + equalities.clear(); + safeDiff = thisDiff; + } else { + if (!equalities.empty()) { + // Throw away the previous equality (it needs to be reevaluated). + equalities.pop(); + } + if (equalities.empty()) { + // There are no previous questionable equalities, + // walk back to the last known safe diff. + thisDiff = safeDiff; + } else { + // There is an equality we can fall back to. + thisDiff = equalities.lastElement(); + } + while (thisDiff != pointer.previous()) { + // Intentionally empty loop. + } + post_ins = post_del = false; + } + + changes = true; + } + } + thisDiff = pointer.hasNext() ? pointer.next() : null; + } + + if (changes) { + diff_cleanupMerge(diffs); + } + } + + + /** + * Reorder and merge like edit sections. Merge equalities. + * Any edit section can move as long as it doesn't cross an equality. + * @param diffs LinkedList of Diff objects. + */ + public void diff_cleanupMerge(LinkedList diffs) { + diffs.add(new Diff(Operation.EQUAL, "")); // Add a dummy entry at the end. + ListIterator pointer = diffs.listIterator(); + int count_delete = 0; + int count_insert = 0; + String text_delete = ""; + String text_insert = ""; + Diff thisDiff = pointer.next(); + Diff prevEqual = null; + int commonlength; + while (thisDiff != null) { + switch (thisDiff.operation) { + case INSERT: + count_insert++; + text_insert += thisDiff.text; + prevEqual = null; + break; + case DELETE: + count_delete++; + text_delete += thisDiff.text; + prevEqual = null; + break; + case EQUAL: + if (count_delete != 0 || count_insert != 0) { + // Delete the offending records. + pointer.previous(); // Reverse direction. + while (count_delete-- > 0) { + pointer.previous(); + pointer.remove(); + } + while (count_insert-- > 0) { + pointer.previous(); + pointer.remove(); + } + if (count_delete != 0 && count_insert != 0) { + // Factor out any common prefixies. + commonlength = diff_commonPrefix(text_insert, text_delete); + if (commonlength != 0) { + if (pointer.hasPrevious()) { + thisDiff = pointer.previous(); + assert thisDiff.operation == Operation.EQUAL + : "Previous diff should have been an equality."; + thisDiff.text += text_insert.substring(0, commonlength); + pointer.next(); + } else { + pointer.add(new Diff(Operation.EQUAL, + text_insert.substring(0, commonlength))); + } + text_insert = text_insert.substring(commonlength); + text_delete = text_delete.substring(commonlength); + } + // Factor out any common suffixies. + commonlength = diff_commonSuffix(text_insert, text_delete); + if (commonlength != 0) { + thisDiff = pointer.next(); + thisDiff.text = text_insert.substring(text_insert.length() + - commonlength) + thisDiff.text; + text_insert = text_insert.substring(0, text_insert.length() + - commonlength); + text_delete = text_delete.substring(0, text_delete.length() + - commonlength); + pointer.previous(); + } + } + // Insert the merged records. + if (text_delete.length() != 0) { + pointer.add(new Diff(Operation.DELETE, text_delete)); + } + if (text_insert.length() != 0) { + pointer.add(new Diff(Operation.INSERT, text_insert)); + } + // Step forward to the equality. + thisDiff = pointer.hasNext() ? pointer.next() : null; + } else if (prevEqual != null) { + // Merge this equality with the previous one. + prevEqual.text += thisDiff.text; + pointer.remove(); + thisDiff = pointer.previous(); + pointer.next(); // Forward direction + } + count_insert = 0; + count_delete = 0; + text_delete = ""; + text_insert = ""; + prevEqual = thisDiff; + break; + } + thisDiff = pointer.hasNext() ? pointer.next() : null; + } + // System.out.println(diff); + if (diffs.getLast().text.length() == 0) { + diffs.removeLast(); // Remove the dummy entry at the end. + } + + /* + * Second pass: look for single edits surrounded on both sides by equalities + * which can be shifted sideways to eliminate an equality. + * e.g: ABAC -> ABAC + */ + boolean changes = false; + // Create a new iterator at the start. + // (As opposed to walking the current one back.) + pointer = diffs.listIterator(); + Diff prevDiff = pointer.hasNext() ? pointer.next() : null; + thisDiff = pointer.hasNext() ? pointer.next() : null; + Diff nextDiff = pointer.hasNext() ? pointer.next() : null; + // Intentionally ignore the first and last element (don't need checking). + while (nextDiff != null) { + if (prevDiff.operation == Operation.EQUAL && + nextDiff.operation == Operation.EQUAL) { + // This is a single edit surrounded by equalities. + if (thisDiff.text.endsWith(prevDiff.text)) { + // Shift the edit over the previous equality. + thisDiff.text = prevDiff.text + + thisDiff.text.substring(0, thisDiff.text.length() + - prevDiff.text.length()); + nextDiff.text = prevDiff.text + nextDiff.text; + pointer.previous(); // Walk past nextDiff. + pointer.previous(); // Walk past thisDiff. + pointer.previous(); // Walk past prevDiff. + pointer.remove(); // Delete prevDiff. + pointer.next(); // Walk past thisDiff. + thisDiff = pointer.next(); // Walk past nextDiff. + nextDiff = pointer.hasNext() ? pointer.next() : null; + changes = true; + } else if (thisDiff.text.startsWith(nextDiff.text)) { + // Shift the edit over the next equality. + prevDiff.text += nextDiff.text; + thisDiff.text = thisDiff.text.substring(nextDiff.text.length()) + + nextDiff.text; + pointer.remove(); // Delete nextDiff. + nextDiff = pointer.hasNext() ? pointer.next() : null; + changes = true; + } + } + prevDiff = thisDiff; + thisDiff = nextDiff; + nextDiff = pointer.hasNext() ? pointer.next() : null; + } + // If shifts were made, the diff needs reordering and another shift sweep. + if (changes) { + diff_cleanupMerge(diffs); + } + } + + + /** + * loc is a location in text1, compute and return the equivalent location in + * text2. + * e.g. "The cat" vs "The big cat", 1->1, 5->8 + * @param diffs LinkedList of Diff objects. + * @param loc Location within text1. + * @return Location within text2. + */ + public int diff_xIndex(LinkedList diffs, int loc) { + int chars1 = 0; + int chars2 = 0; + int last_chars1 = 0; + int last_chars2 = 0; + Diff lastDiff = null; + for (Diff aDiff : diffs) { + if (aDiff.operation != Operation.INSERT) { + // Equality or deletion. + chars1 += aDiff.text.length(); + } + if (aDiff.operation != Operation.DELETE) { + // Equality or insertion. + chars2 += aDiff.text.length(); + } + if (chars1 > loc) { + // Overshot the location. + lastDiff = aDiff; + break; + } + last_chars1 = chars1; + last_chars2 = chars2; + } + if (lastDiff != null && lastDiff.operation == Operation.DELETE) { + // The location was deleted. + return last_chars2; + } + // Add the remaining character length. + return last_chars2 + (loc - last_chars1); + } + + + /** + * Convert a Diff list into a pretty HTML report. + * @param diffs LinkedList of Diff objects. + * @return HTML representation. + */ + public String diff_prettyHtml(LinkedList diffs) { + StringBuilder html = new StringBuilder(); + int i = 0; + for (Diff aDiff : diffs) { + String text = aDiff.text.replace("&", "&").replace("<", "<") + .replace(">", ">").replace("\n", "¶
"); + switch (aDiff.operation) { + case INSERT: + html.append("").append(text).append(""); + break; + case DELETE: + html.append("").append(text).append(""); + break; + case EQUAL: + html.append("").append(text) + .append(""); + break; + } + if (aDiff.operation != Operation.DELETE) { + i += aDiff.text.length(); + } + } + return html.toString(); + } + + + /** + * Compute and return the source text (all equalities and deletions). + * @param diffs LinkedList of Diff objects. + * @return Source text. + */ + public String diff_text1(LinkedList diffs) { + StringBuilder text = new StringBuilder(); + for (Diff aDiff : diffs) { + if (aDiff.operation != Operation.INSERT) { + text.append(aDiff.text); + } + } + return text.toString(); + } + + + /** + * Compute and return the destination text (all equalities and insertions). + * @param diffs LinkedList of Diff objects. + * @return Destination text. + */ + public String diff_text2(LinkedList diffs) { + StringBuilder text = new StringBuilder(); + for (Diff aDiff : diffs) { + if (aDiff.operation != Operation.DELETE) { + text.append(aDiff.text); + } + } + return text.toString(); + } + + + /** + * Compute the Levenshtein distance; the number of inserted, deleted or + * substituted characters. + * @param diffs LinkedList of Diff objects. + * @return Number of changes. + */ + public int diff_levenshtein(LinkedList diffs) { + int levenshtein = 0; + int insertions = 0; + int deletions = 0; + for (Diff aDiff : diffs) { + switch (aDiff.operation) { + case INSERT: + insertions += aDiff.text.length(); + break; + case DELETE: + deletions += aDiff.text.length(); + break; + case EQUAL: + // A deletion and an insertion is one substitution. + levenshtein += Math.max(insertions, deletions); + insertions = 0; + deletions = 0; + break; + } + } + levenshtein += Math.max(insertions, deletions); + return levenshtein; + } + + + /** + * Crush the diff into an encoded string which describes the operations + * required to transform text1 into text2. + * E.g. =3\t-2\t+ing -> Keep 3 chars, delete 2 chars, insert 'ing'. + * Operations are tab-separated. Inserted text is escaped using %xx notation. + * @param diffs Array of diff tuples. + * @return Delta text. + */ + public String diff_toDelta(LinkedList diffs) { + StringBuilder text = new StringBuilder(); + for (Diff aDiff : diffs) { + switch (aDiff.operation) { + case INSERT: + try { + text.append("+").append(URLEncoder.encode(aDiff.text, "UTF-8") + .replace('+', ' ')).append("\t"); + } catch (UnsupportedEncodingException e) { + // Not likely on modern system. + throw new Error("This system does not support UTF-8.", e); + } + break; + case DELETE: + text.append("-").append(aDiff.text.length()).append("\t"); + break; + case EQUAL: + text.append("=").append(aDiff.text.length()).append("\t"); + break; + } + } + String delta = text.toString(); + if (delta.length() != 0) { + // Strip off trailing tab character. + delta = delta.substring(0, delta.length() - 1); + delta = unescapeForEncodeUriCompatability(delta); + } + return delta; + } + + + /** + * Given the original text1, and an encoded string which describes the + * operations required to transform text1 into text2, compute the full diff. + * @param text1 Source string for the diff. + * @param delta Delta text. + * @return Array of diff tuples or null if invalid. + * @throws IllegalArgumentException If invalid input. + */ + public LinkedList diff_fromDelta(String text1, String delta) + throws IllegalArgumentException { + LinkedList diffs = new LinkedList(); + int pointer = 0; // Cursor in text1 + String[] tokens = delta.split("\t"); + for (String token : tokens) { + if (token.length() == 0) { + // Blank tokens are ok (from a trailing \t). + continue; + } + // Each token begins with a one character parameter which specifies the + // operation of this token (delete, insert, equality). + String param = token.substring(1); + switch (token.charAt(0)) { + case '+': + // decode would change all "+" to " " + param = param.replace("+", "%2B"); + try { + param = URLDecoder.decode(param, "UTF-8"); + } catch (UnsupportedEncodingException e) { + // Not likely on modern system. + throw new Error("This system does not support UTF-8.", e); + } catch (IllegalArgumentException e) { + // Malformed URI sequence. + throw new IllegalArgumentException( + "Illegal escape in diff_fromDelta: " + param, e); + } + diffs.add(new Diff(Operation.INSERT, param)); + break; + case '-': + // Fall through. + case '=': + int n; + try { + n = Integer.parseInt(param); + } catch (NumberFormatException e) { + throw new IllegalArgumentException( + "Invalid number in diff_fromDelta: " + param, e); + } + if (n < 0) { + throw new IllegalArgumentException( + "Negative number in diff_fromDelta: " + param); + } + String text; + try { + text = text1.substring(pointer, pointer += n); + } catch (StringIndexOutOfBoundsException e) { + throw new IllegalArgumentException("Delta length (" + pointer + + ") larger than source text length (" + text1.length() + + ").", e); + } + if (token.charAt(0) == '=') { + diffs.add(new Diff(Operation.EQUAL, text)); + } else { + diffs.add(new Diff(Operation.DELETE, text)); + } + break; + default: + // Anything else is an error. + throw new IllegalArgumentException( + "Invalid diff operation in diff_fromDelta: " + token.charAt(0)); + } + } + if (pointer != text1.length()) { + throw new IllegalArgumentException("Delta length (" + pointer + + ") smaller than source text length (" + text1.length() + ")."); + } + return diffs; + } + + + // MATCH FUNCTIONS + + + /** + * Locate the best instance of 'pattern' in 'text' near 'loc'. + * Returns -1 if no match found. + * @param text The text to search. + * @param pattern The pattern to search for. + * @param loc The location to search around. + * @return Best match index or -1. + */ + public int match_main(String text, String pattern, int loc) { + // Check for null inputs. + if (text == null || pattern == null) { + throw new IllegalArgumentException("Null inputs. (match_main)"); + } + + loc = Math.max(0, Math.min(loc, text.length())); + if (text.equals(pattern)) { + // Shortcut (potentially not guaranteed by the algorithm) + return 0; + } else if (text.length() == 0) { + // Nothing to match. + return -1; + } else if (loc + pattern.length() <= text.length() + && text.substring(loc, loc + pattern.length()).equals(pattern)) { + // Perfect match at the perfect spot! (Includes case of null pattern) + return loc; + } else { + // Do a fuzzy compare. + return match_bitap(text, pattern, loc); + } + } + + + /** + * Locate the best instance of 'pattern' in 'text' near 'loc' using the + * Bitap algorithm. Returns -1 if no match found. + * @param text The text to search. + * @param pattern The pattern to search for. + * @param loc The location to search around. + * @return Best match index or -1. + */ + protected int match_bitap(String text, String pattern, int loc) { + assert (Match_MaxBits == 0 || pattern.length() <= Match_MaxBits) + : "Pattern too long for this application."; + + // Initialise the alphabet. + Map s = match_alphabet(pattern); + + // Highest score beyond which we give up. + double score_threshold = Match_Threshold; + // Is there a nearby exact match? (speedup) + int best_loc = text.indexOf(pattern, loc); + if (best_loc != -1) { + score_threshold = Math.min(match_bitapScore(0, best_loc, loc, pattern), + score_threshold); + // What about in the other direction? (speedup) + best_loc = text.lastIndexOf(pattern, loc + pattern.length()); + if (best_loc != -1) { + score_threshold = Math.min(match_bitapScore(0, best_loc, loc, pattern), + score_threshold); + } + } + + // Initialise the bit arrays. + int matchmask = 1 << (pattern.length() - 1); + best_loc = -1; + + int bin_min, bin_mid; + int bin_max = pattern.length() + text.length(); + // Empty initialization added to appease Java compiler. + int[] last_rd = new int[0]; + for (int d = 0; d < pattern.length(); d++) { + // Scan for the best match; each iteration allows for one more error. + // Run a binary search to determine how far from 'loc' we can stray at + // this error level. + bin_min = 0; + bin_mid = bin_max; + while (bin_min < bin_mid) { + if (match_bitapScore(d, loc + bin_mid, loc, pattern) + <= score_threshold) { + bin_min = bin_mid; + } else { + bin_max = bin_mid; + } + bin_mid = (bin_max - bin_min) / 2 + bin_min; + } + // Use the result from this iteration as the maximum for the next. + bin_max = bin_mid; + int start = Math.max(1, loc - bin_mid + 1); + int finish = Math.min(loc + bin_mid, text.length()) + pattern.length(); + + int[] rd = new int[finish + 2]; + rd[finish + 1] = (1 << d) - 1; + for (int j = finish; j >= start; j--) { + int charMatch; + if (text.length() <= j - 1 || !s.containsKey(text.charAt(j - 1))) { + // Out of range. + charMatch = 0; + } else { + charMatch = s.get(text.charAt(j - 1)); + } + if (d == 0) { + // First pass: exact match. + rd[j] = ((rd[j + 1] << 1) | 1) & charMatch; + } else { + // Subsequent passes: fuzzy match. + rd[j] = ((rd[j + 1] << 1) | 1) & charMatch + | (((last_rd[j + 1] | last_rd[j]) << 1) | 1) | last_rd[j + 1]; + } + if ((rd[j] & matchmask) != 0) { + double score = match_bitapScore(d, j - 1, loc, pattern); + // This match will almost certainly be better than any existing + // match. But check anyway. + if (score <= score_threshold) { + // Told you so. + score_threshold = score; + best_loc = j - 1; + if (best_loc > loc) { + // When passing loc, don't exceed our current distance from loc. + start = Math.max(1, 2 * loc - best_loc); + } else { + // Already passed loc, downhill from here on in. + break; + } + } + } + } + if (match_bitapScore(d + 1, loc, loc, pattern) > score_threshold) { + // No hope for a (better) match at greater error levels. + break; + } + last_rd = rd; + } + return best_loc; + } + + + /** + * Compute and return the score for a match with e errors and x location. + * @param e Number of errors in match. + * @param x Location of match. + * @param loc Expected location of match. + * @param pattern Pattern being sought. + * @return Overall score for match (0.0 = good, 1.0 = bad). + */ + private double match_bitapScore(int e, int x, int loc, String pattern) { + float accuracy = (float) e / pattern.length(); + int proximity = Math.abs(loc - x); + if (Match_Distance == 0) { + // Dodge divide by zero error. + return proximity == 0 ? accuracy : 1.0; + } + return accuracy + (proximity / (float) Match_Distance); + } + + + /** + * Initialise the alphabet for the Bitap algorithm. + * @param pattern The text to encode. + * @return Hash of character locations. + */ + protected Map match_alphabet(String pattern) { + Map s = new HashMap(); + char[] char_pattern = pattern.toCharArray(); + for (char c : char_pattern) { + s.put(c, 0); + } + int i = 0; + for (char c : char_pattern) { + s.put(c, s.get(c) | (1 << (pattern.length() - i - 1))); + i++; + } + return s; + } + + + // PATCH FUNCTIONS + + + /** + * Increase the context until it is unique, + * but don't let the pattern expand beyond Match_MaxBits. + * @param patch The patch to grow. + * @param text Source text. + */ + protected void patch_addContext(Patch patch, String text) { + if (text.length() == 0) { + return; + } + String pattern = text.substring(patch.start2, patch.start2 + patch.length1); + int padding = 0; + + // Look for the first and last matches of pattern in text. If two different + // matches are found, increase the pattern length. + while (text.indexOf(pattern) != text.lastIndexOf(pattern) + && pattern.length() < Match_MaxBits - Patch_Margin - Patch_Margin) { + padding += Patch_Margin; + pattern = text.substring(Math.max(0, patch.start2 - padding), + Math.min(text.length(), patch.start2 + patch.length1 + padding)); + } + // Add one chunk for good luck. + padding += Patch_Margin; + + // Add the prefix. + String prefix = text.substring(Math.max(0, patch.start2 - padding), + patch.start2); + if (prefix.length() != 0) { + patch.diffs.addFirst(new Diff(Operation.EQUAL, prefix)); + } + // Add the suffix. + String suffix = text.substring(patch.start2 + patch.length1, + Math.min(text.length(), patch.start2 + patch.length1 + padding)); + if (suffix.length() != 0) { + patch.diffs.addLast(new Diff(Operation.EQUAL, suffix)); + } + + // Roll back the start points. + patch.start1 -= prefix.length(); + patch.start2 -= prefix.length(); + // Extend the lengths. + patch.length1 += prefix.length() + suffix.length(); + patch.length2 += prefix.length() + suffix.length(); + } + + + /** + * Compute a list of patches to turn text1 into text2. + * A set of diffs will be computed. + * @param text1 Old text. + * @param text2 New text. + * @return LinkedList of Patch objects. + */ + public LinkedList patch_make(String text1, String text2) { + if (text1 == null || text2 == null) { + throw new IllegalArgumentException("Null inputs. (patch_make)"); + } + // No diffs provided, compute our own. + LinkedList diffs = diff_main(text1, text2, true); + if (diffs.size() > 2) { + diff_cleanupSemantic(diffs); + diff_cleanupEfficiency(diffs); + } + return patch_make(text1, diffs); + } + + + /** + * Compute a list of patches to turn text1 into text2. + * text1 will be derived from the provided diffs. + * @param diffs Array of diff tuples for text1 to text2. + * @return LinkedList of Patch objects. + */ + public LinkedList patch_make(LinkedList diffs) { + if (diffs == null) { + throw new IllegalArgumentException("Null inputs. (patch_make)"); + } + // No origin string provided, compute our own. + String text1 = diff_text1(diffs); + return patch_make(text1, diffs); + } + + + /** + * Compute a list of patches to turn text1 into text2. + * text2 is ignored, diffs are the delta between text1 and text2. + * @param text1 Old text + * @param text2 Ignored. + * @param diffs Array of diff tuples for text1 to text2. + * @return LinkedList of Patch objects. + * @deprecated Prefer patch_make(String text1, LinkedList diffs). + */ + public LinkedList patch_make(String text1, String text2, + LinkedList diffs) { + return patch_make(text1, diffs); + } + + + /** + * Compute a list of patches to turn text1 into text2. + * text2 is not provided, diffs are the delta between text1 and text2. + * @param text1 Old text. + * @param diffs Array of diff tuples for text1 to text2. + * @return LinkedList of Patch objects. + */ + public LinkedList patch_make(String text1, LinkedList diffs) { + if (text1 == null || diffs == null) { + throw new IllegalArgumentException("Null inputs. (patch_make)"); + } + + LinkedList patches = new LinkedList(); + if (diffs.isEmpty()) { + return patches; // Get rid of the null case. + } + Patch patch = new Patch(); + int char_count1 = 0; // Number of characters into the text1 string. + int char_count2 = 0; // Number of characters into the text2 string. + // Start with text1 (prepatch_text) and apply the diffs until we arrive at + // text2 (postpatch_text). We recreate the patches one by one to determine + // context info. + String prepatch_text = text1; + String postpatch_text = text1; + for (Diff aDiff : diffs) { + if (patch.diffs.isEmpty() && aDiff.operation != Operation.EQUAL) { + // A new patch starts here. + patch.start1 = char_count1; + patch.start2 = char_count2; + } + + switch (aDiff.operation) { + case INSERT: + patch.diffs.add(aDiff); + patch.length2 += aDiff.text.length(); + postpatch_text = postpatch_text.substring(0, char_count2) + + aDiff.text + postpatch_text.substring(char_count2); + break; + case DELETE: + patch.length1 += aDiff.text.length(); + patch.diffs.add(aDiff); + postpatch_text = postpatch_text.substring(0, char_count2) + + postpatch_text.substring(char_count2 + aDiff.text.length()); + break; + case EQUAL: + if (aDiff.text.length() <= 2 * Patch_Margin + && !patch.diffs.isEmpty() && aDiff != diffs.getLast()) { + // Small equality inside a patch. + patch.diffs.add(aDiff); + patch.length1 += aDiff.text.length(); + patch.length2 += aDiff.text.length(); + } + + if (aDiff.text.length() >= 2 * Patch_Margin) { + // Time for a new patch. + if (!patch.diffs.isEmpty()) { + patch_addContext(patch, prepatch_text); + patches.add(patch); + patch = new Patch(); + // Unlike Unidiff, our patch lists have a rolling context. + // http://code.google.com/p/google-diff-match-patch/wiki/Unidiff + // Update prepatch text & pos to reflect the application of the + // just completed patch. + prepatch_text = postpatch_text; + char_count1 = char_count2; + } + } + break; + } + + // Update the current character count. + if (aDiff.operation != Operation.INSERT) { + char_count1 += aDiff.text.length(); + } + if (aDiff.operation != Operation.DELETE) { + char_count2 += aDiff.text.length(); + } + } + // Pick up the leftover patch if not empty. + if (!patch.diffs.isEmpty()) { + patch_addContext(patch, prepatch_text); + patches.add(patch); + } + + return patches; + } + + + /** + * Given an array of patches, return another array that is identical. + * @param patches Array of patch objects. + * @return Array of patch objects. + */ + public LinkedList patch_deepCopy(LinkedList patches) { + LinkedList patchesCopy = new LinkedList(); + for (Patch aPatch : patches) { + Patch patchCopy = new Patch(); + for (Diff aDiff : aPatch.diffs) { + Diff diffCopy = new Diff(aDiff.operation, aDiff.text); + patchCopy.diffs.add(diffCopy); + } + patchCopy.start1 = aPatch.start1; + patchCopy.start2 = aPatch.start2; + patchCopy.length1 = aPatch.length1; + patchCopy.length2 = aPatch.length2; + patchesCopy.add(patchCopy); + } + return patchesCopy; + } + + + /** + * Merge a set of patches onto the text. Return a patched text, as well + * as an array of true/false values indicating which patches were applied. + * @param patches Array of patch objects + * @param text Old text. + * @return Two element Object array, containing the new text and an array of + * boolean values. + */ + public Object[] patch_apply(LinkedList patches, String text) { + if (patches.isEmpty()) { + return new Object[]{text, new boolean[0]}; + } + + // Deep copy the patches so that no changes are made to originals. + patches = patch_deepCopy(patches); + + String nullPadding = patch_addPadding(patches); + text = nullPadding + text + nullPadding; + patch_splitMax(patches); + + int x = 0; + // delta keeps track of the offset between the expected and actual location + // of the previous patch. If there are patches expected at positions 10 and + // 20, but the first patch was found at 12, delta is 2 and the second patch + // has an effective expected position of 22. + int delta = 0; + boolean[] results = new boolean[patches.size()]; + for (Patch aPatch : patches) { + int expected_loc = aPatch.start2 + delta; + String text1 = diff_text1(aPatch.diffs); + int start_loc; + int end_loc = -1; + if (text1.length() > this.Match_MaxBits) { + // patch_splitMax will only provide an oversized pattern in the case of + // a monster delete. + start_loc = match_main(text, + text1.substring(0, this.Match_MaxBits), expected_loc); + if (start_loc != -1) { + end_loc = match_main(text, + text1.substring(text1.length() - this.Match_MaxBits), + expected_loc + text1.length() - this.Match_MaxBits); + if (end_loc == -1 || start_loc >= end_loc) { + // Can't find valid trailing context. Drop this patch. + start_loc = -1; + } + } + } else { + start_loc = match_main(text, text1, expected_loc); + } + if (start_loc == -1) { + // No match found. :( + results[x] = false; + // Subtract the delta for this failed patch from subsequent patches. + delta -= aPatch.length2 - aPatch.length1; + } else { + // Found a match. :) + results[x] = true; + delta = start_loc - expected_loc; + String text2; + if (end_loc == -1) { + text2 = text.substring(start_loc, + Math.min(start_loc + text1.length(), text.length())); + } else { + text2 = text.substring(start_loc, + Math.min(end_loc + this.Match_MaxBits, text.length())); + } + if (text1.equals(text2)) { + // Perfect match, just shove the replacement text in. + text = text.substring(0, start_loc) + diff_text2(aPatch.diffs) + + text.substring(start_loc + text1.length()); + } else { + // Imperfect match. Run a diff to get a framework of equivalent + // indices. + LinkedList diffs = diff_main(text1, text2, false); + if (text1.length() > this.Match_MaxBits + && diff_levenshtein(diffs) / (float) text1.length() + > this.Patch_DeleteThreshold) { + // The end points match, but the content is unacceptably bad. + results[x] = false; + } else { + diff_cleanupSemanticLossless(diffs); + int index1 = 0; + for (Diff aDiff : aPatch.diffs) { + if (aDiff.operation != Operation.EQUAL) { + int index2 = diff_xIndex(diffs, index1); + if (aDiff.operation == Operation.INSERT) { + // Insertion + text = text.substring(0, start_loc + index2) + aDiff.text + + text.substring(start_loc + index2); + } else if (aDiff.operation == Operation.DELETE) { + // Deletion + text = text.substring(0, start_loc + index2) + + text.substring(start_loc + diff_xIndex(diffs, + index1 + aDiff.text.length())); + } + } + if (aDiff.operation != Operation.DELETE) { + index1 += aDiff.text.length(); + } + } + } + } + } + x++; + } + // Strip the padding off. + text = text.substring(nullPadding.length(), text.length() + - nullPadding.length()); + return new Object[]{text, results}; + } + + + /** + * Add some padding on text start and end so that edges can match something. + * Intended to be called only from within patch_apply. + * @param patches Array of patch objects. + * @return The padding string added to each side. + */ + public String patch_addPadding(LinkedList patches) { + int paddingLength = this.Patch_Margin; + String nullPadding = ""; + for (int x = 1; x <= paddingLength; x++) { + nullPadding += String.valueOf((char) x); + } + + // Bump all the patches forward. + for (Patch aPatch : patches) { + aPatch.start1 += paddingLength; + aPatch.start2 += paddingLength; + } + + // Add some padding on start of first diff. + Patch patch = patches.getFirst(); + LinkedList diffs = patch.diffs; + if (diffs.isEmpty() || diffs.getFirst().operation != Operation.EQUAL) { + // Add nullPadding equality. + diffs.addFirst(new Diff(Operation.EQUAL, nullPadding)); + patch.start1 -= paddingLength; // Should be 0. + patch.start2 -= paddingLength; // Should be 0. + patch.length1 += paddingLength; + patch.length2 += paddingLength; + } else if (paddingLength > diffs.getFirst().text.length()) { + // Grow first equality. + Diff firstDiff = diffs.getFirst(); + int extraLength = paddingLength - firstDiff.text.length(); + firstDiff.text = nullPadding.substring(firstDiff.text.length()) + + firstDiff.text; + patch.start1 -= extraLength; + patch.start2 -= extraLength; + patch.length1 += extraLength; + patch.length2 += extraLength; + } + + // Add some padding on end of last diff. + patch = patches.getLast(); + diffs = patch.diffs; + if (diffs.isEmpty() || diffs.getLast().operation != Operation.EQUAL) { + // Add nullPadding equality. + diffs.addLast(new Diff(Operation.EQUAL, nullPadding)); + patch.length1 += paddingLength; + patch.length2 += paddingLength; + } else if (paddingLength > diffs.getLast().text.length()) { + // Grow last equality. + Diff lastDiff = diffs.getLast(); + int extraLength = paddingLength - lastDiff.text.length(); + lastDiff.text += nullPadding.substring(0, extraLength); + patch.length1 += extraLength; + patch.length2 += extraLength; + } + + return nullPadding; + } + + + /** + * Look through the patches and break up any which are longer than the + * maximum limit of the match algorithm. + * @param patches LinkedList of Patch objects. + */ + public void patch_splitMax(LinkedList patches) { + int patch_size; + String precontext, postcontext; + Patch patch; + int start1, start2; + boolean empty; + Operation diff_type; + String diff_text; + ListIterator pointer = patches.listIterator(); + Patch bigpatch = pointer.hasNext() ? pointer.next() : null; + while (bigpatch != null) { + if (bigpatch.length1 <= Match_MaxBits) { + bigpatch = pointer.hasNext() ? pointer.next() : null; + continue; + } + // Remove the big old patch. + pointer.remove(); + patch_size = Match_MaxBits; + start1 = bigpatch.start1; + start2 = bigpatch.start2; + precontext = ""; + while (!bigpatch.diffs.isEmpty()) { + // Create one of several smaller patches. + patch = new Patch(); + empty = true; + patch.start1 = start1 - precontext.length(); + patch.start2 = start2 - precontext.length(); + if (precontext.length() != 0) { + patch.length1 = patch.length2 = precontext.length(); + patch.diffs.add(new Diff(Operation.EQUAL, precontext)); + } + while (!bigpatch.diffs.isEmpty() + && patch.length1 < patch_size - Patch_Margin) { + diff_type = bigpatch.diffs.getFirst().operation; + diff_text = bigpatch.diffs.getFirst().text; + if (diff_type == Operation.INSERT) { + // Insertions are harmless. + patch.length2 += diff_text.length(); + start2 += diff_text.length(); + patch.diffs.addLast(bigpatch.diffs.removeFirst()); + empty = false; + } else if (diff_type == Operation.DELETE && patch.diffs.size() == 1 + && patch.diffs.getFirst().operation == Operation.EQUAL + && diff_text.length() > 2 * patch_size) { + // This is a large deletion. Let it pass in one chunk. + patch.length1 += diff_text.length(); + start1 += diff_text.length(); + empty = false; + patch.diffs.add(new Diff(diff_type, diff_text)); + bigpatch.diffs.removeFirst(); + } else { + // Deletion or equality. Only take as much as we can stomach. + diff_text = diff_text.substring(0, Math.min(diff_text.length(), + patch_size - patch.length1 - Patch_Margin)); + patch.length1 += diff_text.length(); + start1 += diff_text.length(); + if (diff_type == Operation.EQUAL) { + patch.length2 += diff_text.length(); + start2 += diff_text.length(); + } else { + empty = false; + } + patch.diffs.add(new Diff(diff_type, diff_text)); + if (diff_text.equals(bigpatch.diffs.getFirst().text)) { + bigpatch.diffs.removeFirst(); + } else { + bigpatch.diffs.getFirst().text = bigpatch.diffs.getFirst().text + .substring(diff_text.length()); + } + } + } + // Compute the head context for the next patch. + precontext = diff_text2(patch.diffs); + precontext = precontext.substring(Math.max(0, precontext.length() + - Patch_Margin)); + // Append the end context for this patch. + if (diff_text1(bigpatch.diffs).length() > Patch_Margin) { + postcontext = diff_text1(bigpatch.diffs).substring(0, Patch_Margin); + } else { + postcontext = diff_text1(bigpatch.diffs); + } + if (postcontext.length() != 0) { + patch.length1 += postcontext.length(); + patch.length2 += postcontext.length(); + if (!patch.diffs.isEmpty() + && patch.diffs.getLast().operation == Operation.EQUAL) { + patch.diffs.getLast().text += postcontext; + } else { + patch.diffs.add(new Diff(Operation.EQUAL, postcontext)); + } + } + if (!empty) { + pointer.add(patch); + } + } + bigpatch = pointer.hasNext() ? pointer.next() : null; + } + } + + + /** + * Take a list of patches and return a textual representation. + * @param patches List of Patch objects. + * @return Text representation of patches. + */ + public String patch_toText(List patches) { + StringBuilder text = new StringBuilder(); + for (Patch aPatch : patches) { + text.append(aPatch); + } + return text.toString(); + } + + + /** + * Parse a textual representation of patches and return a List of Patch + * objects. + * @param textline Text representation of patches. + * @return List of Patch objects. + * @throws IllegalArgumentException If invalid input. + */ + public List patch_fromText(String textline) + throws IllegalArgumentException { + List patches = new LinkedList(); + if (textline.length() == 0) { + return patches; + } + List textList = Arrays.asList(textline.split("\n")); + LinkedList text = new LinkedList(textList); + Patch patch; + Pattern patchHeader + = Pattern.compile("^@@ -(\\d+),?(\\d*) \\+(\\d+),?(\\d*) @@$"); + Matcher m; + char sign; + String line; + while (!text.isEmpty()) { + m = patchHeader.matcher(text.getFirst()); + if (!m.matches()) { + throw new IllegalArgumentException( + "Invalid patch string: " + text.getFirst()); + } + patch = new Patch(); + patches.add(patch); + patch.start1 = Integer.parseInt(m.group(1)); + if (m.group(2).length() == 0) { + patch.start1--; + patch.length1 = 1; + } else if (m.group(2).equals("0")) { + patch.length1 = 0; + } else { + patch.start1--; + patch.length1 = Integer.parseInt(m.group(2)); + } + + patch.start2 = Integer.parseInt(m.group(3)); + if (m.group(4).length() == 0) { + patch.start2--; + patch.length2 = 1; + } else if (m.group(4).equals("0")) { + patch.length2 = 0; + } else { + patch.start2--; + patch.length2 = Integer.parseInt(m.group(4)); + } + text.removeFirst(); + + while (!text.isEmpty()) { + try { + sign = text.getFirst().charAt(0); + } catch (IndexOutOfBoundsException e) { + // Blank line? Whatever. + text.removeFirst(); + continue; + } + line = text.getFirst().substring(1); + line = line.replace("+", "%2B"); // decode would change all "+" to " " + try { + line = URLDecoder.decode(line, "UTF-8"); + } catch (UnsupportedEncodingException e) { + // Not likely on modern system. + throw new Error("This system does not support UTF-8.", e); + } catch (IllegalArgumentException e) { + // Malformed URI sequence. + throw new IllegalArgumentException( + "Illegal escape in patch_fromText: " + line, e); + } + if (sign == '-') { + // Deletion. + patch.diffs.add(new Diff(Operation.DELETE, line)); + } else if (sign == '+') { + // Insertion. + patch.diffs.add(new Diff(Operation.INSERT, line)); + } else if (sign == ' ') { + // Minor equality. + patch.diffs.add(new Diff(Operation.EQUAL, line)); + } else if (sign == '@') { + // Start of next patch. + break; + } else { + // WTF? + throw new IllegalArgumentException( + "Invalid patch mode '" + sign + "' in: " + line); + } + text.removeFirst(); + } + } + return patches; + } + + + /** + * Class representing one diff operation. + */ + public static class Diff { + /** + * One of: INSERT, DELETE or EQUAL. + */ + public Operation operation; + /** + * The text associated with this diff operation. + */ + public String text; + + /** + * Constructor. Initializes the diff with the provided values. + * @param operation One of INSERT, DELETE or EQUAL. + * @param text The text being applied. + */ + public Diff(Operation operation, String text) { + // Construct a diff with the specified operation and text. + this.operation = operation; + this.text = text; + } + + + /** + * Display a human-readable version of this Diff. + * @return text version. + */ + public String toString() { + String prettyText = this.text.replace('\n', '\u00b6'); + return "Diff(" + this.operation + ",\"" + prettyText + "\")"; + } + + + /** + * Is this Diff equivalent to another Diff? + * @param d Another Diff to compare against. + * @return true or false. + */ + public boolean equals(Object d) { + try { + return (((Diff) d).operation == this.operation) + && (((Diff) d).text.equals(this.text)); + } catch (ClassCastException e) { + return false; + } + } + } + + + /** + * Class representing one patch operation. + */ + public static class Patch { + public LinkedList diffs; + public int start1; + public int start2; + public int length1; + public int length2; + + + /** + * Constructor. Initializes with an empty list of diffs. + */ + public Patch() { + this.diffs = new LinkedList(); + } + + + /** + * Emmulate GNU diff's format. + * Header: @@ -382,8 +481,9 @@ + * Indicies are printed as 1-based, not 0-based. + * @return The GNU diff string. + */ + public String toString() { + String coords1, coords2; + if (this.length1 == 0) { + coords1 = this.start1 + ",0"; + } else if (this.length1 == 1) { + coords1 = Integer.toString(this.start1 + 1); + } else { + coords1 = (this.start1 + 1) + "," + this.length1; + } + if (this.length2 == 0) { + coords2 = this.start2 + ",0"; + } else if (this.length2 == 1) { + coords2 = Integer.toString(this.start2 + 1); + } else { + coords2 = (this.start2 + 1) + "," + this.length2; + } + StringBuilder text = new StringBuilder(); + text.append("@@ -").append(coords1).append(" +").append(coords2) + .append(" @@\n"); + // Escape the body of the patch with %xx notation. + for (Diff aDiff : this.diffs) { + switch (aDiff.operation) { + case INSERT: + text.append('+'); + break; + case DELETE: + text.append('-'); + break; + case EQUAL: + text.append(' '); + break; + } + try { + text.append(URLEncoder.encode(aDiff.text, "UTF-8").replace('+', ' ')) + .append("\n"); + } catch (UnsupportedEncodingException e) { + // Not likely on modern system. + throw new Error("This system does not support UTF-8.", e); + } + } + return unescapeForEncodeUriCompatability(text.toString()); + } + } + + + /** + * Unescape selected chars for compatability with JavaScript's encodeURI. + * In speed critical applications this could be dropped since the + * receiving application will certainly decode these fine. + * Note that this function is case-sensitive. Thus "%3f" would not be + * unescaped. But this is ok because it is only called with the output of + * URLEncoder.encode which returns uppercase hex. + * + * Example: "%3F" -> "?", "%24" -> "$", etc. + * + * @param str The string to escape. + * @return The escaped string. + */ + private static String unescapeForEncodeUriCompatability(String str) { + return str.replace("%21", "!").replace("%7E", "~") + .replace("%27", "'").replace("%28", "(").replace("%29", ")") + .replace("%3B", ";").replace("%2F", "/").replace("%3F", "?") + .replace("%3A", ":").replace("%40", "@").replace("%26", "&") + .replace("%3D", "=").replace("%2B", "+").replace("%24", "$") + .replace("%2C", ",").replace("%23", "#"); + } +} diff --git a/name/fraser/neil/plaintext/diff_match_patch_test.java b/name/fraser/neil/plaintext/diff_match_patch_test.java new file mode 100644 index 0000000..a920315 --- /dev/null +++ b/name/fraser/neil/plaintext/diff_match_patch_test.java @@ -0,0 +1,945 @@ +/* + * Test harness for diff_match_patch.java + * + * Copyright 2006 Google Inc. + * http://code.google.com/p/google-diff-match-patch/ + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package name.fraser.neil.plaintext; + +import junit.framework.TestCase; + +import java.util.ArrayList; +import java.util.Arrays; +import java.util.HashMap; +import java.util.HashSet; +import java.util.LinkedList; +import java.util.List; +import java.util.Map; +import java.util.Set; + +import name.fraser.neil.plaintext.diff_match_patch.Diff; +import name.fraser.neil.plaintext.diff_match_patch.LinesToCharsResult; +import name.fraser.neil.plaintext.diff_match_patch.Patch; + +public class diff_match_patch_test extends TestCase { + + private diff_match_patch dmp; + private diff_match_patch.Operation DELETE = diff_match_patch.Operation.DELETE; + private diff_match_patch.Operation EQUAL = diff_match_patch.Operation.EQUAL; + private diff_match_patch.Operation INSERT = diff_match_patch.Operation.INSERT; + + protected void setUp() { + // Create an instance of the diff_match_patch object. + dmp = new diff_match_patch(); + } + + + // DIFF TEST FUNCTIONS + + + public void testDiffCommonPrefix() { + // Detect and remove any common prefix. + assertEquals("diff_commonPrefix: Null case.", 0, dmp.diff_commonPrefix("abc", "xyz")); + + assertEquals("diff_commonPrefix: Non-null case.", 4, dmp.diff_commonPrefix("1234abcdef", "1234xyz")); + + assertEquals("diff_commonPrefix: Whole case.", 4, dmp.diff_commonPrefix("1234", "1234xyz")); + } + + public void testDiffCommonSuffix() { + // Detect and remove any common suffix. + assertEquals("diff_commonSuffix: Null case.", 0, dmp.diff_commonSuffix("abc", "xyz")); + + assertEquals("diff_commonSuffix: Non-null case.", 4, dmp.diff_commonSuffix("abcdef1234", "xyz1234")); + + assertEquals("diff_commonSuffix: Whole case.", 4, dmp.diff_commonSuffix("1234", "xyz1234")); + } + + public void testDiffHalfmatch() { + // Detect a halfmatch. + assertNull("diff_halfMatch: No match.", dmp.diff_halfMatch("1234567890", "abcdef")); + + assertArrayEquals("diff_halfMatch: Single Match #1.", new String[]{"12", "90", "a", "z", "345678"}, dmp.diff_halfMatch("1234567890", "a345678z")); + + assertArrayEquals("diff_halfMatch: Single Match #2.", new String[]{"a", "z", "12", "90", "345678"}, dmp.diff_halfMatch("a345678z", "1234567890")); + + assertArrayEquals("diff_halfMatch: Multiple Matches #1.", new String[]{"12123", "123121", "a", "z", "1234123451234"}, dmp.diff_halfMatch("121231234123451234123121", "a1234123451234z")); + + assertArrayEquals("diff_halfMatch: Multiple Matches #2.", new String[]{"", "-=-=-=-=-=", "x", "", "x-=-=-=-=-=-=-="}, dmp.diff_halfMatch("x-=-=-=-=-=-=-=-=-=-=-=-=", "xx-=-=-=-=-=-=-=")); + + assertArrayEquals("diff_halfMatch: Multiple Matches #3.", new String[]{"-=-=-=-=-=", "", "", "y", "-=-=-=-=-=-=-=y"}, dmp.diff_halfMatch("-=-=-=-=-=-=-=-=-=-=-=-=y", "-=-=-=-=-=-=-=yy")); + } + + public void testDiffLinesToChars() { + // Convert lines down to characters. + ArrayList tmpVector = new ArrayList(); + tmpVector.add(""); + tmpVector.add("alpha\n"); + tmpVector.add("beta\n"); + assertLinesToCharsResultEquals("diff_linesToChars:", new LinesToCharsResult("\u0001\u0002\u0001", "\u0002\u0001\u0002", tmpVector), dmp.diff_linesToChars("alpha\nbeta\nalpha\n", "beta\nalpha\nbeta\n")); + + tmpVector.clear(); + tmpVector.add(""); + tmpVector.add("alpha\r\n"); + tmpVector.add("beta\r\n"); + tmpVector.add("\r\n"); + assertLinesToCharsResultEquals("diff_linesToChars:", new LinesToCharsResult("", "\u0001\u0002\u0003\u0003", tmpVector), dmp.diff_linesToChars("", "alpha\r\nbeta\r\n\r\n\r\n")); + + tmpVector.clear(); + tmpVector.add(""); + tmpVector.add("a"); + tmpVector.add("b"); + assertLinesToCharsResultEquals("diff_linesToChars:", new LinesToCharsResult("\u0001", "\u0002", tmpVector), dmp.diff_linesToChars("a", "b")); + + // More than 256 to reveal any 8-bit limitations. + int n = 300; + tmpVector.clear(); + StringBuilder lineList = new StringBuilder(); + StringBuilder charList = new StringBuilder(); + for (int x = 1; x < n + 1; x++) { + tmpVector.add(x + "\n"); + lineList.append(x + "\n"); + charList.append(String.valueOf((char) x)); + } + assertEquals(n, tmpVector.size()); + String lines = lineList.toString(); + String chars = charList.toString(); + assertEquals(n, chars.length()); + tmpVector.add(0, ""); + assertLinesToCharsResultEquals("diff_linesToChars: More than 256.", new LinesToCharsResult(chars, "", tmpVector), dmp.diff_linesToChars(lines, "")); + } + + public void testDiffCharsToLines() { + // First check that Diff equality works. + assertTrue("diff_charsToLines:", new Diff(EQUAL, "a").equals(new Diff(EQUAL, "a"))); + + assertEquals("diff_charsToLines:", new Diff(EQUAL, "a"), new Diff(EQUAL, "a")); + + // Convert chars up to lines + LinkedList diffs = diffList(new Diff(EQUAL, "\u0001\u0002\u0001"), new Diff(INSERT, "\u0002\u0001\u0002")); + ArrayList tmpVector = new ArrayList(); + tmpVector.add(""); + tmpVector.add("alpha\n"); + tmpVector.add("beta\n"); + dmp.diff_charsToLines(diffs, tmpVector); + assertEquals("diff_charsToLines:", diffList(new Diff(EQUAL, "alpha\nbeta\nalpha\n"), new Diff(INSERT, "beta\nalpha\nbeta\n")), diffs); + + // More than 256 to reveal any 8-bit limitations. + int n = 300; + tmpVector.clear(); + StringBuilder lineList = new StringBuilder(); + StringBuilder charList = new StringBuilder(); + for (int x = 1; x < n + 1; x++) { + tmpVector.add(x + "\n"); + lineList.append(x + "\n"); + charList.append(String.valueOf((char) x)); + } + assertEquals(n, tmpVector.size()); + String lines = lineList.toString(); + String chars = charList.toString(); + assertEquals(n, chars.length()); + tmpVector.add(0, ""); + diffs = diffList(new Diff(DELETE, chars)); + dmp.diff_charsToLines(diffs, tmpVector); + assertEquals("diff_charsToLines: More than 256.", diffList(new Diff(DELETE, lines)), diffs); + } + + public void testDiffCleanupMerge() { + // Cleanup a messy diff. + LinkedList diffs = diffList(); + dmp.diff_cleanupMerge(diffs); + assertEquals("diff_cleanupMerge: Null case.", diffList(), diffs); + + diffs = diffList(new Diff(EQUAL, "a"), new Diff(DELETE, "b"), new Diff(INSERT, "c")); + dmp.diff_cleanupMerge(diffs); + assertEquals("diff_cleanupMerge: No change case.", diffList(new Diff(EQUAL, "a"), new Diff(DELETE, "b"), new Diff(INSERT, "c")), diffs); + + diffs = diffList(new Diff(EQUAL, "a"), new Diff(EQUAL, "b"), new Diff(EQUAL, "c")); + dmp.diff_cleanupMerge(diffs); + assertEquals("diff_cleanupMerge: Merge equalities.", diffList(new Diff(EQUAL, "abc")), diffs); + + diffs = diffList(new Diff(DELETE, "a"), new Diff(DELETE, "b"), new Diff(DELETE, "c")); + dmp.diff_cleanupMerge(diffs); + assertEquals("diff_cleanupMerge: Merge deletions.", diffList(new Diff(DELETE, "abc")), diffs); + + diffs = diffList(new Diff(INSERT, "a"), new Diff(INSERT, "b"), new Diff(INSERT, "c")); + dmp.diff_cleanupMerge(diffs); + assertEquals("diff_cleanupMerge: Merge insertions.", diffList(new Diff(INSERT, "abc")), diffs); + + diffs = diffList(new Diff(DELETE, "a"), new Diff(INSERT, "b"), new Diff(DELETE, "c"), new Diff(INSERT, "d"), new Diff(EQUAL, "e"), new Diff(EQUAL, "f")); + dmp.diff_cleanupMerge(diffs); + assertEquals("diff_cleanupMerge: Merge interweave.", diffList(new Diff(DELETE, "ac"), new Diff(INSERT, "bd"), new Diff(EQUAL, "ef")), diffs); + + diffs = diffList(new Diff(DELETE, "a"), new Diff(INSERT, "abc"), new Diff(DELETE, "dc")); + dmp.diff_cleanupMerge(diffs); + assertEquals("diff_cleanupMerge: Prefix and suffix detection.", diffList(new Diff(EQUAL, "a"), new Diff(DELETE, "d"), new Diff(INSERT, "b"), new Diff(EQUAL, "c")), diffs); + + diffs = diffList(new Diff(EQUAL, "a"), new Diff(INSERT, "ba"), new Diff(EQUAL, "c")); + dmp.diff_cleanupMerge(diffs); + assertEquals("diff_cleanupMerge: Slide edit left.", diffList(new Diff(INSERT, "ab"), new Diff(EQUAL, "ac")), diffs); + + diffs = diffList(new Diff(EQUAL, "c"), new Diff(INSERT, "ab"), new Diff(EQUAL, "a")); + dmp.diff_cleanupMerge(diffs); + assertEquals("diff_cleanupMerge: Slide edit right.", diffList(new Diff(EQUAL, "ca"), new Diff(INSERT, "ba")), diffs); + + diffs = diffList(new Diff(EQUAL, "a"), new Diff(DELETE, "b"), new Diff(EQUAL, "c"), new Diff(DELETE, "ac"), new Diff(EQUAL, "x")); + dmp.diff_cleanupMerge(diffs); + assertEquals("diff_cleanupMerge: Slide edit left recursive.", diffList(new Diff(DELETE, "abc"), new Diff(EQUAL, "acx")), diffs); + + diffs = diffList(new Diff(EQUAL, "x"), new Diff(DELETE, "ca"), new Diff(EQUAL, "c"), new Diff(DELETE, "b"), new Diff(EQUAL, "a")); + dmp.diff_cleanupMerge(diffs); + assertEquals("diff_cleanupMerge: Slide edit right recursive.", diffList(new Diff(EQUAL, "xca"), new Diff(DELETE, "cba")), diffs); + } + + public void testDiffCleanupSemanticLossless() { + // Slide diffs to match logical boundaries. + LinkedList diffs = diffList(); + dmp.diff_cleanupSemanticLossless(diffs); + assertEquals("diff_cleanupSemanticLossless: Null case.", diffList(), diffs); + + diffs = diffList(new Diff(EQUAL, "AAA\r\n\r\nBBB"), new Diff(INSERT, "\r\nDDD\r\n\r\nBBB"), new Diff(EQUAL, "\r\nEEE")); + dmp.diff_cleanupSemanticLossless(diffs); + assertEquals("diff_cleanupSemanticLossless: Blank lines.", diffList(new Diff(EQUAL, "AAA\r\n\r\n"), new Diff(INSERT, "BBB\r\nDDD\r\n\r\n"), new Diff(EQUAL, "BBB\r\nEEE")), diffs); + + diffs = diffList(new Diff(EQUAL, "AAA\r\nBBB"), new Diff(INSERT, " DDD\r\nBBB"), new Diff(EQUAL, " EEE")); + dmp.diff_cleanupSemanticLossless(diffs); + assertEquals("diff_cleanupSemanticLossless: Line boundaries.", diffList(new Diff(EQUAL, "AAA\r\n"), new Diff(INSERT, "BBB DDD\r\n"), new Diff(EQUAL, "BBB EEE")), diffs); + + diffs = diffList(new Diff(EQUAL, "The c"), new Diff(INSERT, "ow and the c"), new Diff(EQUAL, "at.")); + dmp.diff_cleanupSemanticLossless(diffs); + assertEquals("diff_cleanupSemanticLossless: Word boundaries.", diffList(new Diff(EQUAL, "The "), new Diff(INSERT, "cow and the "), new Diff(EQUAL, "cat.")), diffs); + + diffs = diffList(new Diff(EQUAL, "The-c"), new Diff(INSERT, "ow-and-the-c"), new Diff(EQUAL, "at.")); + dmp.diff_cleanupSemanticLossless(diffs); + assertEquals("diff_cleanupSemanticLossless: Alphanumeric boundaries.", diffList(new Diff(EQUAL, "The-"), new Diff(INSERT, "cow-and-the-"), new Diff(EQUAL, "cat.")), diffs); + + diffs = diffList(new Diff(EQUAL, "a"), new Diff(DELETE, "a"), new Diff(EQUAL, "ax")); + dmp.diff_cleanupSemanticLossless(diffs); + assertEquals("diff_cleanupSemanticLossless: Hitting the start.", diffList(new Diff(DELETE, "a"), new Diff(EQUAL, "aax")), diffs); + + diffs = diffList(new Diff(EQUAL, "xa"), new Diff(DELETE, "a"), new Diff(EQUAL, "a")); + dmp.diff_cleanupSemanticLossless(diffs); + assertEquals("diff_cleanupSemanticLossless: Hitting the end.", diffList(new Diff(EQUAL, "xaa"), new Diff(DELETE, "a")), diffs); + } + + public void testDiffCleanupSemantic() { + // Cleanup semantically trivial equalities. + LinkedList diffs = diffList(); + dmp.diff_cleanupSemantic(diffs); + assertEquals("diff_cleanupSemantic: Null case.", diffList(), diffs); + + diffs = diffList(new Diff(DELETE, "a"), new Diff(INSERT, "b"), new Diff(EQUAL, "cd"), new Diff(DELETE, "e")); + dmp.diff_cleanupSemantic(diffs); + assertEquals("diff_cleanupSemantic: No elimination.", diffList(new Diff(DELETE, "a"), new Diff(INSERT, "b"), new Diff(EQUAL, "cd"), new Diff(DELETE, "e")), diffs); + + diffs = diffList(new Diff(DELETE, "a"), new Diff(EQUAL, "b"), new Diff(DELETE, "c")); + dmp.diff_cleanupSemantic(diffs); + assertEquals("diff_cleanupSemantic: Simple elimination.", diffList(new Diff(DELETE, "abc"), new Diff(INSERT, "b")), diffs); + + diffs = diffList(new Diff(DELETE, "ab"), new Diff(EQUAL, "cd"), new Diff(DELETE, "e"), new Diff(EQUAL, "f"), new Diff(INSERT, "g")); + dmp.diff_cleanupSemantic(diffs); + assertEquals("diff_cleanupSemantic: Backpass elimination.", diffList(new Diff(DELETE, "abcdef"), new Diff(INSERT, "cdfg")), diffs); + + diffs = diffList(new Diff(INSERT, "1"), new Diff(EQUAL, "A"), new Diff(DELETE, "B"), new Diff(INSERT, "2"), new Diff(EQUAL, "_"), new Diff(INSERT, "1"), new Diff(EQUAL, "A"), new Diff(DELETE, "B"), new Diff(INSERT, "2")); + dmp.diff_cleanupSemantic(diffs); + assertEquals("diff_cleanupSemantic: Multiple elimination.", diffList(new Diff(DELETE, "AB_AB"), new Diff(INSERT, "1A2_1A2")), diffs); + + diffs = diffList(new Diff(EQUAL, "The c"), new Diff(DELETE, "ow and the c"), new Diff(EQUAL, "at.")); + dmp.diff_cleanupSemantic(diffs); + assertEquals("diff_cleanupSemantic: Word boundaries.", diffList(new Diff(EQUAL, "The "), new Diff(DELETE, "cow and the "), new Diff(EQUAL, "cat.")), diffs); + } + + public void testDiffCleanupEfficiency() { + // Cleanup operationally trivial equalities. + dmp.Diff_EditCost = 4; + LinkedList diffs = diffList(); + dmp.diff_cleanupEfficiency(diffs); + assertEquals("diff_cleanupEfficiency: Null case.", diffList(), diffs); + + diffs = diffList(new Diff(DELETE, "ab"), new Diff(INSERT, "12"), new Diff(EQUAL, "wxyz"), new Diff(DELETE, "cd"), new Diff(INSERT, "34")); + dmp.diff_cleanupEfficiency(diffs); + assertEquals("diff_cleanupEfficiency: No elimination.", diffList(new Diff(DELETE, "ab"), new Diff(INSERT, "12"), new Diff(EQUAL, "wxyz"), new Diff(DELETE, "cd"), new Diff(INSERT, "34")), diffs); + + diffs = diffList(new Diff(DELETE, "ab"), new Diff(INSERT, "12"), new Diff(EQUAL, "xyz"), new Diff(DELETE, "cd"), new Diff(INSERT, "34")); + dmp.diff_cleanupEfficiency(diffs); + assertEquals("diff_cleanupEfficiency: Four-edit elimination.", diffList(new Diff(DELETE, "abxyzcd"), new Diff(INSERT, "12xyz34")), diffs); + + diffs = diffList(new Diff(INSERT, "12"), new Diff(EQUAL, "x"), new Diff(DELETE, "cd"), new Diff(INSERT, "34")); + dmp.diff_cleanupEfficiency(diffs); + assertEquals("diff_cleanupEfficiency: Three-edit elimination.", diffList(new Diff(DELETE, "xcd"), new Diff(INSERT, "12x34")), diffs); + + diffs = diffList(new Diff(DELETE, "ab"), new Diff(INSERT, "12"), new Diff(EQUAL, "xy"), new Diff(INSERT, "34"), new Diff(EQUAL, "z"), new Diff(DELETE, "cd"), new Diff(INSERT, "56")); + dmp.diff_cleanupEfficiency(diffs); + assertEquals("diff_cleanupEfficiency: Backpass elimination.", diffList(new Diff(DELETE, "abxyzcd"), new Diff(INSERT, "12xy34z56")), diffs); + + dmp.Diff_EditCost = 5; + diffs = diffList(new Diff(DELETE, "ab"), new Diff(INSERT, "12"), new Diff(EQUAL, "wxyz"), new Diff(DELETE, "cd"), new Diff(INSERT, "34")); + dmp.diff_cleanupEfficiency(diffs); + assertEquals("diff_cleanupEfficiency: High cost elimination.", diffList(new Diff(DELETE, "abwxyzcd"), new Diff(INSERT, "12wxyz34")), diffs); + dmp.Diff_EditCost = 4; + } + + public void testDiffPrettyHtml() { + // Pretty print. + LinkedList diffs = diffList(new Diff(EQUAL, "a\n"), new Diff(DELETE, "b"), new Diff(INSERT, "c&d")); + assertEquals("diff_prettyHtml:", "a¶
<B>b</B>c&d", dmp.diff_prettyHtml(diffs)); + } + + public void testDiffText() { + // Compute the source and destination texts. + LinkedList diffs = diffList(new Diff(EQUAL, "jump"), new Diff(DELETE, "s"), new Diff(INSERT, "ed"), new Diff(EQUAL, " over "), new Diff(DELETE, "the"), new Diff(INSERT, "a"), new Diff(EQUAL, " lazy")); + assertEquals("diff_text1:", "jumps over the lazy", dmp.diff_text1(diffs)); + assertEquals("diff_text2:", "jumped over a lazy", dmp.diff_text2(diffs)); + } + + public void testDiffDelta() { + // Convert a diff into delta string. + LinkedList diffs = diffList(new Diff(EQUAL, "jump"), new Diff(DELETE, "s"), new Diff(INSERT, "ed"), new Diff(EQUAL, " over "), new Diff(DELETE, "the"), new Diff(INSERT, "a"), new Diff(EQUAL, " lazy"), new Diff(INSERT, "old dog")); + String text1 = dmp.diff_text1(diffs); + assertEquals("diff_text1: Base text.", "jumps over the lazy", text1); + + String delta = dmp.diff_toDelta(diffs); + assertEquals("diff_toDelta:", "=4\t-1\t+ed\t=6\t-3\t+a\t=5\t+old dog", delta); + + // Convert delta string into a diff. + assertEquals("diff_fromDelta: Normal.", diffs, dmp.diff_fromDelta(text1, delta)); + + // Generates error (19 < 20). + try { + dmp.diff_fromDelta(text1 + "x", delta); + fail("diff_fromDelta: Too long."); + } catch (IllegalArgumentException ex) { + // Exception expected. + } + + // Generates error (19 > 18). + try { + dmp.diff_fromDelta(text1.substring(1), delta); + fail("diff_fromDelta: Too short."); + } catch (IllegalArgumentException ex) { + // Exception expected. + } + + // Generates error (%c3%xy invalid Unicode). + try { + dmp.diff_fromDelta("", "+%c3%xy"); + fail("diff_fromDelta: Invalid character."); + } catch (IllegalArgumentException ex) { + // Exception expected. + } + + // Test deltas with special characters. + diffs = diffList(new Diff(EQUAL, "\u0680 \000 \t %"), new Diff(DELETE, "\u0681 \001 \n ^"), new Diff(INSERT, "\u0682 \002 \\ |")); + text1 = dmp.diff_text1(diffs); + assertEquals("diff_text1: Unicode text.", "\u0680 \000 \t %\u0681 \001 \n ^", text1); + + delta = dmp.diff_toDelta(diffs); + assertEquals("diff_toDelta: Unicode.", "=7\t-7\t+%DA%82 %02 %5C %7C", delta); + + assertEquals("diff_fromDelta: Unicode.", diffs, dmp.diff_fromDelta(text1, delta)); + + // Verify pool of unchanged characters. + diffs = diffList(new Diff(INSERT, "A-Z a-z 0-9 - _ . ! ~ * ' ( ) ; / ? : @ & = + $ , # ")); + String text2 = dmp.diff_text2(diffs); + assertEquals("diff_text2: Unchanged characters.", "A-Z a-z 0-9 - _ . ! ~ * \' ( ) ; / ? : @ & = + $ , # ", text2); + + delta = dmp.diff_toDelta(diffs); + assertEquals("diff_toDelta: Unchanged characters.", "+A-Z a-z 0-9 - _ . ! ~ * \' ( ) ; / ? : @ & = + $ , # ", delta); + + // Convert delta string into a diff. + assertEquals("diff_fromDelta: Unchanged characters.", diffs, dmp.diff_fromDelta("", delta)); + } + + public void testDiffXIndex() { + // Translate a location in text1 to text2. + LinkedList diffs = diffList(new Diff(DELETE, "a"), new Diff(INSERT, "1234"), new Diff(EQUAL, "xyz")); + assertEquals("diff_xIndex: Translation on equality.", 5, dmp.diff_xIndex(diffs, 2)); + + diffs = diffList(new Diff(EQUAL, "a"), new Diff(DELETE, "1234"), new Diff(EQUAL, "xyz")); + assertEquals("diff_xIndex: Translation on deletion.", 1, dmp.diff_xIndex(diffs, 3)); + } + + public void testDiffLevenshtein() { + LinkedList diffs = diffList(new Diff(DELETE, "abc"), new Diff(INSERT, "1234"), new Diff(EQUAL, "xyz")); + assertEquals("Levenshtein with trailing equality.", 4, dmp.diff_levenshtein(diffs)); + + diffs = diffList(new Diff(EQUAL, "xyz"), new Diff(DELETE, "abc"), new Diff(INSERT, "1234")); + assertEquals("Levenshtein with leading equality.", 4, dmp.diff_levenshtein(diffs)); + + diffs = diffList(new Diff(DELETE, "abc"), new Diff(EQUAL, "xyz"), new Diff(INSERT, "1234")); + assertEquals("Levenshtein with middle equality.", 7, dmp.diff_levenshtein(diffs)); + } + + public void testDiffPath() { + // First, check footprints are different. + assertTrue("diff_footprint:", dmp.diff_footprint(1, 10) != dmp.diff_footprint(10, 1)); + + // Single letters. + // Trace a path from back to front. + List> v_map; + Set row_set; + v_map = new ArrayList>(); + { + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 0)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 1)); + row_set.add(dmp.diff_footprint(1, 0)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 2)); + row_set.add(dmp.diff_footprint(2, 0)); + row_set.add(dmp.diff_footprint(2, 2)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 3)); + row_set.add(dmp.diff_footprint(2, 3)); + row_set.add(dmp.diff_footprint(3, 0)); + row_set.add(dmp.diff_footprint(4, 3)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 4)); + row_set.add(dmp.diff_footprint(2, 4)); + row_set.add(dmp.diff_footprint(4, 0)); + row_set.add(dmp.diff_footprint(4, 4)); + row_set.add(dmp.diff_footprint(5, 3)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 5)); + row_set.add(dmp.diff_footprint(2, 5)); + row_set.add(dmp.diff_footprint(4, 5)); + row_set.add(dmp.diff_footprint(5, 0)); + row_set.add(dmp.diff_footprint(6, 3)); + row_set.add(dmp.diff_footprint(6, 5)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 6)); + row_set.add(dmp.diff_footprint(2, 6)); + row_set.add(dmp.diff_footprint(4, 6)); + row_set.add(dmp.diff_footprint(6, 6)); + row_set.add(dmp.diff_footprint(7, 5)); + v_map.add(row_set); + } + LinkedList diffs = diffList(new Diff(INSERT, "W"), new Diff(DELETE, "A"), new Diff(EQUAL, "1"), new Diff(DELETE, "B"), new Diff(EQUAL, "2"), new Diff(INSERT, "X"), new Diff(DELETE, "C"), new Diff(EQUAL, "3"), new Diff(DELETE, "D")); + assertEquals("diff_path1: Single letters.", diffs, dmp.diff_path1(v_map, "A1B2C3D", "W12X3")); + + // Trace a path from front to back. + v_map.remove(v_map.size() - 1); + diffs = diffList(new Diff(EQUAL, "4"), new Diff(DELETE, "E"), new Diff(INSERT, "Y"), new Diff(EQUAL, "5"), new Diff(DELETE, "F"), new Diff(EQUAL, "6"), new Diff(DELETE, "G"), new Diff(INSERT, "Z")); + assertEquals("diff_path2: Single letters.", diffs, dmp.diff_path2(v_map, "4E5F6G", "4Y56Z")); + + // Double letters. + // Trace a path from back to front. + v_map = new ArrayList>(); + { + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 0)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 1)); + row_set.add(dmp.diff_footprint(1, 0)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 2)); + row_set.add(dmp.diff_footprint(1, 1)); + row_set.add(dmp.diff_footprint(2, 0)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 3)); + row_set.add(dmp.diff_footprint(1, 2)); + row_set.add(dmp.diff_footprint(2, 1)); + row_set.add(dmp.diff_footprint(3, 0)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 4)); + row_set.add(dmp.diff_footprint(1, 3)); + row_set.add(dmp.diff_footprint(3, 1)); + row_set.add(dmp.diff_footprint(4, 0)); + row_set.add(dmp.diff_footprint(4, 4)); + v_map.add(row_set); + } + diffs = diffList(new Diff(INSERT, "WX"), new Diff(DELETE, "AB"), new Diff(EQUAL, "12")); + assertEquals("diff_path1: Double letters.", diffs, dmp.diff_path1(v_map, "AB12", "WX12")); + + // Trace a path from front to back. + v_map = new ArrayList>(); + { + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 0)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(0, 1)); + row_set.add(dmp.diff_footprint(1, 0)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(1, 1)); + row_set.add(dmp.diff_footprint(2, 0)); + row_set.add(dmp.diff_footprint(2, 4)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(2, 1)); + row_set.add(dmp.diff_footprint(2, 5)); + row_set.add(dmp.diff_footprint(3, 0)); + row_set.add(dmp.diff_footprint(3, 4)); + v_map.add(row_set); + row_set = new HashSet(); + row_set.add(dmp.diff_footprint(2, 6)); + row_set.add(dmp.diff_footprint(3, 5)); + row_set.add(dmp.diff_footprint(4, 4)); + v_map.add(row_set); + } + diffs = diffList(new Diff(DELETE, "CD"), new Diff(EQUAL, "34"), new Diff(INSERT, "YZ")); + assertEquals("diff_path2: Double letters.", diffs, dmp.diff_path2(v_map, "CD34", "34YZ")); + } + + public void testDiffMain() { + // Perform a trivial diff. + LinkedList diffs = diffList(new Diff(EQUAL, "abc")); + assertEquals("diff_main: Null case.", diffs, dmp.diff_main("abc", "abc", false)); + + diffs = diffList(new Diff(EQUAL, "ab"), new Diff(INSERT, "123"), new Diff(EQUAL, "c")); + assertEquals("diff_main: Simple insertion.", diffs, dmp.diff_main("abc", "ab123c", false)); + + diffs = diffList(new Diff(EQUAL, "a"), new Diff(DELETE, "123"), new Diff(EQUAL, "bc")); + assertEquals("diff_main: Simple deletion.", diffs, dmp.diff_main("a123bc", "abc", false)); + + diffs = diffList(new Diff(EQUAL, "a"), new Diff(INSERT, "123"), new Diff(EQUAL, "b"), new Diff(INSERT, "456"), new Diff(EQUAL, "c")); + assertEquals("diff_main: Two insertions.", diffs, dmp.diff_main("abc", "a123b456c", false)); + + diffs = diffList(new Diff(EQUAL, "a"), new Diff(DELETE, "123"), new Diff(EQUAL, "b"), new Diff(DELETE, "456"), new Diff(EQUAL, "c")); + assertEquals("diff_main: Two deletions.", diffs, dmp.diff_main("a123b456c", "abc", false)); + + // Perform a real diff. + // Switch off the timeout. + dmp.Diff_Timeout = 0; + dmp.Diff_DualThreshold = 32; + diffs = diffList(new Diff(DELETE, "a"), new Diff(INSERT, "b")); + assertEquals("diff_main: Simple case #1.", diffs, dmp.diff_main("a", "b", false)); + + diffs = diffList(new Diff(DELETE, "Apple"), new Diff(INSERT, "Banana"), new Diff(EQUAL, "s are a"), new Diff(INSERT, "lso"), new Diff(EQUAL, " fruit.")); + assertEquals("diff_main: Simple case #2.", diffs, dmp.diff_main("Apples are a fruit.", "Bananas are also fruit.", false)); + + diffs = diffList(new Diff(DELETE, "a"), new Diff(INSERT, "\u0680"), new Diff(EQUAL, "x"), new Diff(DELETE, "\t"), new Diff(INSERT, "\000")); + assertEquals("diff_main: Simple case #3.", diffs, dmp.diff_main("ax\t", "\u0680x\000", false)); + + diffs = diffList(new Diff(DELETE, "1"), new Diff(EQUAL, "a"), new Diff(DELETE, "y"), new Diff(EQUAL, "b"), new Diff(DELETE, "2"), new Diff(INSERT, "xab")); + assertEquals("diff_main: Overlap #1.", diffs, dmp.diff_main("1ayb2", "abxab", false)); + + diffs = diffList(new Diff(INSERT, "xaxcx"), new Diff(EQUAL, "abc"), new Diff(DELETE, "y")); + assertEquals("diff_main: Overlap #2.", diffs, dmp.diff_main("abcy", "xaxcxabc", false)); + + // Sub-optimal double-ended diff. + dmp.Diff_DualThreshold = 2; + diffs = diffList(new Diff(INSERT, "x"), new Diff(EQUAL, "a"), new Diff(DELETE, "b"), new Diff(INSERT, "x"), new Diff(EQUAL, "c"), new Diff(DELETE, "y"), new Diff(INSERT, "xabc")); + assertEquals("diff_main: Overlap #3.", diffs, dmp.diff_main("abcy", "xaxcxabc", false)); + + dmp.Diff_DualThreshold = 32; + dmp.Diff_Timeout = 0.001f; // 1ms + String a = "`Twas brillig, and the slithy toves\nDid gyre and gimble in the wabe:\nAll mimsy were the borogoves,\nAnd the mome raths outgrabe.\n"; + String b = "I am the very model of a modern major general,\nI've information vegetable, animal, and mineral,\nI know the kings of England, and I quote the fights historical,\nFrom Marathon to Waterloo, in order categorical.\n"; + // Increase the text lengths by 1024 times to ensure a timeout. + for (int x = 0; x < 10; x++) { + a = a + a; + b = b + b; + } + assertNull("diff_main: Timeout.", dmp.diff_map(a, b)); + dmp.Diff_Timeout = 0; + + // Test the linemode speedup. + // Must be long to pass the 200 char cutoff. + a = "1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n"; + b = "abcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\n"; + assertEquals("diff_main: Simple.", dmp.diff_main(a, b, true), dmp.diff_main(a, b, false)); + + a = "1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n"; + b = "abcdefghij\n1234567890\n1234567890\n1234567890\nabcdefghij\n1234567890\n1234567890\n1234567890\nabcdefghij\n1234567890\n1234567890\n1234567890\nabcdefghij\n"; + String[] texts_linemode = diff_rebuildtexts(dmp.diff_main(a, b, true)); + String[] texts_textmode = diff_rebuildtexts(dmp.diff_main(a, b, false)); + assertArrayEquals("diff_main: Overlap.", texts_textmode, texts_linemode); + + // Test null inputs. + try { + dmp.diff_main(null, null); + fail("diff_main: Null inputs."); + } catch (IllegalArgumentException ex) { + // Error expected. + } + } + + + // MATCH TEST FUNCTIONS + + + public void testMatchAlphabet() { + // Initialise the bitmasks for Bitap. + Map bitmask; + bitmask = new HashMap(); + bitmask.put('a', 4); bitmask.put('b', 2); bitmask.put('c', 1); + assertEquals("match_alphabet: Unique.", bitmask, dmp.match_alphabet("abc")); + + bitmask = new HashMap(); + bitmask.put('a', 37); bitmask.put('b', 18); bitmask.put('c', 8); + assertEquals("match_alphabet: Duplicates.", bitmask, dmp.match_alphabet("abcaba")); + } + + public void testMatchBitap() { + // Bitap algorithm. + dmp.Match_Distance = 100; + dmp.Match_Threshold = 0.5f; + assertEquals("match_bitap: Exact match #1.", 5, dmp.match_bitap("abcdefghijk", "fgh", 5)); + + assertEquals("match_bitap: Exact match #2.", 5, dmp.match_bitap("abcdefghijk", "fgh", 0)); + + assertEquals("match_bitap: Fuzzy match #1.", 4, dmp.match_bitap("abcdefghijk", "efxhi", 0)); + + assertEquals("match_bitap: Fuzzy match #2.", 2, dmp.match_bitap("abcdefghijk", "cdefxyhijk", 5)); + + assertEquals("match_bitap: Fuzzy match #3.", -1, dmp.match_bitap("abcdefghijk", "bxy", 1)); + + assertEquals("match_bitap: Overflow.", 2, dmp.match_bitap("123456789xx0", "3456789x0", 2)); + + assertEquals("match_bitap: Before start match.", 0, dmp.match_bitap("abcdef", "xxabc", 4)); + + assertEquals("match_bitap: Beyond end match.", 3, dmp.match_bitap("abcdef", "defyy", 4)); + + assertEquals("match_bitap: Oversized pattern.", 0, dmp.match_bitap("abcdef", "xabcdefy", 0)); + + dmp.Match_Threshold = 0.4f; + assertEquals("match_bitap: Threshold #1.", 4, dmp.match_bitap("abcdefghijk", "efxyhi", 1)); + + dmp.Match_Threshold = 0.3f; + assertEquals("match_bitap: Threshold #2.", -1, dmp.match_bitap("abcdefghijk", "efxyhi", 1)); + + dmp.Match_Threshold = 0.0f; + assertEquals("match_bitap: Threshold #3.", 1, dmp.match_bitap("abcdefghijk", "bcdef", 1)); + + dmp.Match_Threshold = 0.5f; + assertEquals("match_bitap: Multiple select #1.", 0, dmp.match_bitap("abcdexyzabcde", "abccde", 3)); + + assertEquals("match_bitap: Multiple select #2.", 8, dmp.match_bitap("abcdexyzabcde", "abccde", 5)); + + dmp.Match_Distance = 10; // Strict location. + assertEquals("match_bitap: Distance test #1.", -1, dmp.match_bitap("abcdefghijklmnopqrstuvwxyz", "abcdefg", 24)); + + assertEquals("match_bitap: Distance test #2.", 0, dmp.match_bitap("abcdefghijklmnopqrstuvwxyz", "abcdxxefg", 1)); + + dmp.Match_Distance = 1000; // Loose location. + assertEquals("match_bitap: Distance test #3.", 0, dmp.match_bitap("abcdefghijklmnopqrstuvwxyz", "abcdefg", 24)); + } + + public void testMatchMain() { + // Full match. + assertEquals("match_main: Equality.", 0, dmp.match_main("abcdef", "abcdef", 1000)); + + assertEquals("match_main: Null text.", -1, dmp.match_main("", "abcdef", 1)); + + assertEquals("match_main: Null pattern.", 3, dmp.match_main("abcdef", "", 3)); + + assertEquals("match_main: Exact match.", 3, dmp.match_main("abcdef", "de", 3)); + + assertEquals("match_main: Beyond end match.", 3, dmp.match_main("abcdef", "defy", 4)); + + assertEquals("match_main: Oversized pattern.", 0, dmp.match_main("abcdef", "abcdefy", 0)); + + dmp.Match_Threshold = 0.7f; + assertEquals("match_main: Complex match.", 4, dmp.match_main("I am the very model of a modern major general.", " that berry ", 5)); + dmp.Match_Threshold = 0.5f; + + // Test null inputs. + try { + dmp.match_main(null, null, 0); + fail("match_main: Null inputs."); + } catch (IllegalArgumentException ex) { + // Error expected. + } + } + + + // PATCH TEST FUNCTIONS + + + public void testPatchObj() { + // Patch Object. + Patch p = new Patch(); + p.start1 = 20; + p.start2 = 21; + p.length1 = 18; + p.length2 = 17; + p.diffs = diffList(new Diff(EQUAL, "jump"), new Diff(DELETE, "s"), new Diff(INSERT, "ed"), new Diff(EQUAL, " over "), new Diff(DELETE, "the"), new Diff(INSERT, "a"), new Diff(EQUAL, "\nlaz")); + String strp = "@@ -21,18 +22,17 @@\n jump\n-s\n+ed\n over \n-the\n+a\n %0Alaz\n"; + assertEquals("Patch: toString.", strp, p.toString()); + } + + public void testPatchFromText() { + assertTrue("patch_fromText: #0.", dmp.patch_fromText("").isEmpty()); + + String strp = "@@ -21,18 +22,17 @@\n jump\n-s\n+ed\n over \n-the\n+a\n %0Alaz\n"; + assertEquals("patch_fromText: #1.", strp, dmp.patch_fromText(strp).get(0).toString()); + + assertEquals("patch_fromText: #2.", "@@ -1 +1 @@\n-a\n+b\n", dmp.patch_fromText("@@ -1 +1 @@\n-a\n+b\n").get(0).toString()); + + assertEquals("patch_fromText: #3.", "@@ -1,3 +0,0 @@\n-abc\n", dmp.patch_fromText("@@ -1,3 +0,0 @@\n-abc\n").get(0).toString()); + + assertEquals("patch_fromText: #4.", "@@ -0,0 +1,3 @@\n+abc\n", dmp.patch_fromText("@@ -0,0 +1,3 @@\n+abc\n").get(0).toString()); + + // Generates error. + try { + dmp.patch_fromText("Bad\nPatch\n"); + fail("patch_fromText: #5."); + } catch (IllegalArgumentException ex) { + // Exception expected. + } + } + + public void testPatchToText() { + String strp = "@@ -21,18 +22,17 @@\n jump\n-s\n+ed\n over \n-the\n+a\n laz\n"; + List patches; + patches = dmp.patch_fromText(strp); + assertEquals("patch_toText: Single", strp, dmp.patch_toText(patches)); + + strp = "@@ -1,9 +1,9 @@\n-f\n+F\n oo+fooba\n@@ -7,9 +7,9 @@\n obar\n-,\n+.\n tes\n"; + patches = dmp.patch_fromText(strp); + assertEquals("patch_toText: Dual", strp, dmp.patch_toText(patches)); + } + + public void testPatchAddContext() { + dmp.Patch_Margin = 4; + Patch p; + p = dmp.patch_fromText("@@ -21,4 +21,10 @@\n-jump\n+somersault\n").get(0); + dmp.patch_addContext(p, "The quick brown fox jumps over the lazy dog."); + assertEquals("patch_addContext: Simple case.", "@@ -17,12 +17,18 @@\n fox \n-jump\n+somersault\n s ov\n", p.toString()); + + p = dmp.patch_fromText("@@ -21,4 +21,10 @@\n-jump\n+somersault\n").get(0); + dmp.patch_addContext(p, "The quick brown fox jumps."); + assertEquals("patch_addContext: Not enough trailing context.", "@@ -17,10 +17,16 @@\n fox \n-jump\n+somersault\n s.\n", p.toString()); + + p = dmp.patch_fromText("@@ -3 +3,2 @@\n-e\n+at\n").get(0); + dmp.patch_addContext(p, "The quick brown fox jumps."); + assertEquals("patch_addContext: Not enough leading context.", "@@ -1,7 +1,8 @@\n Th\n-e\n+at\n qui\n", p.toString()); + + p = dmp.patch_fromText("@@ -3 +3,2 @@\n-e\n+at\n").get(0); + dmp.patch_addContext(p, "The quick brown fox jumps. The quick brown fox crashes."); + assertEquals("patch_addContext: Ambiguity.", "@@ -1,27 +1,28 @@\n Th\n-e\n+at\n quick brown fox jumps. \n", p.toString()); + } + + @SuppressWarnings("deprecation") + public void testPatchMake() { + LinkedList patches; + String text1 = "The quick brown fox jumps over the lazy dog."; + String text2 = "That quick brown fox jumped over a lazy dog."; + String expectedPatch = "@@ -1,8 +1,7 @@\n Th\n-at\n+e\n qui\n@@ -21,17 +21,18 @@\n jump\n-ed\n+s\n over \n-a\n+the\n laz\n"; + // The second patch must be "-21,17 +21,18", not "-22,17 +21,18" due to rolling context. + patches = dmp.patch_make(text2, text1); + assertEquals("patch_make: Text2+Text1 inputs", expectedPatch, dmp.patch_toText(patches)); + + expectedPatch = "@@ -1,11 +1,12 @@\n Th\n-e\n+at\n quick b\n@@ -22,18 +22,17 @@\n jump\n-s\n+ed\n over \n-the\n+a\n laz\n"; + patches = dmp.patch_make(text1, text2); + assertEquals("patch_make: Text1+Text2 inputs", expectedPatch, dmp.patch_toText(patches)); + + LinkedList diffs = dmp.diff_main(text1, text2, false); + patches = dmp.patch_make(diffs); + assertEquals("patch_make: Diff input", expectedPatch, dmp.patch_toText(patches)); + + patches = dmp.patch_make(text1, diffs); + assertEquals("patch_make: Text1+Diff inputs", expectedPatch, dmp.patch_toText(patches)); + + patches = dmp.patch_make(text1, text2, diffs); + assertEquals("patch_make: Text1+Text2+Diff inputs (deprecated)", expectedPatch, dmp.patch_toText(patches)); + + patches = dmp.patch_make("`1234567890-=[]\\;',./", "~!@#$%^&*()_+{}|:\"<>?"); + assertEquals("patch_toText: Character encoding.", "@@ -1,21 +1,21 @@\n-%601234567890-=%5B%5D%5C;',./\n+~!@#$%25%5E&*()_+%7B%7D%7C:%22%3C%3E?\n", dmp.patch_toText(patches)); + + diffs = diffList(new Diff(DELETE, "`1234567890-=[]\\;',./"), new Diff(INSERT, "~!@#$%^&*()_+{}|:\"<>?")); + assertEquals("patch_fromText: Character decoding.", diffs, dmp.patch_fromText("@@ -1,21 +1,21 @@\n-%601234567890-=%5B%5D%5C;',./\n+~!@#$%25%5E&*()_+%7B%7D%7C:%22%3C%3E?\n").get(0).diffs); + + text1 = ""; + for (int x = 0; x < 100; x++) { + text1 += "abcdef"; + } + text2 = text1 + "123"; + expectedPatch = "@@ -573,28 +573,31 @@\n cdefabcdefabcdefabcdefabcdef\n+123\n"; + patches = dmp.patch_make(text1, text2); + assertEquals("patch_make: Long string with repeats.", expectedPatch, dmp.patch_toText(patches)); + + // Test null inputs. + try { + dmp.patch_make(null); + fail("patch_make: Null inputs."); + } catch (IllegalArgumentException ex) { + // Error expected. + } + } + + public void testPatchSplitMax() { + // Assumes that Match_MaxBits is 32. + LinkedList patches; + patches = dmp.patch_make("abcdefghijklmnopqrstuvwxyz01234567890", "XabXcdXefXghXijXklXmnXopXqrXstXuvXwxXyzX01X23X45X67X89X0"); + dmp.patch_splitMax(patches); + assertEquals("patch_splitMax: #1.", "@@ -1,32 +1,46 @@\n+X\n ab\n+X\n cd\n+X\n ef\n+X\n gh\n+X\n ij\n+X\n kl\n+X\n mn\n+X\n op\n+X\n qr\n+X\n st\n+X\n uv\n+X\n wx\n+X\n yz\n+X\n 012345\n@@ -25,13 +39,18 @@\n zX01\n+X\n 23\n+X\n 45\n+X\n 67\n+X\n 89\n+X\n 0\n", dmp.patch_toText(patches)); + + patches = dmp.patch_make("abcdef1234567890123456789012345678901234567890123456789012345678901234567890uvwxyz", "abcdefuvwxyz"); + String oldToText = dmp.patch_toText(patches); + dmp.patch_splitMax(patches); + assertEquals("patch_splitMax: #2.", oldToText, dmp.patch_toText(patches)); + + patches = dmp.patch_make("1234567890123456789012345678901234567890123456789012345678901234567890", "abc"); + dmp.patch_splitMax(patches); + assertEquals("patch_splitMax: #3.", "@@ -1,32 +1,4 @@\n-1234567890123456789012345678\n 9012\n@@ -29,32 +1,4 @@\n-9012345678901234567890123456\n 7890\n@@ -57,14 +1,3 @@\n-78901234567890\n+abc\n", dmp.patch_toText(patches)); + + patches = dmp.patch_make("abcdefghij , h : 0 , t : 1 abcdefghij , h : 0 , t : 1 abcdefghij , h : 0 , t : 1", "abcdefghij , h : 1 , t : 1 abcdefghij , h : 1 , t : 1 abcdefghij , h : 0 , t : 1"); + dmp.patch_splitMax(patches); + assertEquals("patch_splitMax: #4.", "@@ -2,32 +2,32 @@\n bcdefghij , h : \n-0\n+1\n , t : 1 abcdef\n@@ -29,32 +29,32 @@\n bcdefghij , h : \n-0\n+1\n , t : 1 abcdef\n", dmp.patch_toText(patches)); + } + + public void testPatchAddPadding() { + LinkedList patches; + patches = dmp.patch_make("", "test"); + assertEquals("patch_addPadding: Both edges full.", "@@ -0,0 +1,4 @@\n+test\n", dmp.patch_toText(patches)); + dmp.patch_addPadding(patches); + assertEquals("patch_addPadding: Both edges full.", "@@ -1,8 +1,12 @@\n %01%02%03%04\n+test\n %01%02%03%04\n", dmp.patch_toText(patches)); + + patches = dmp.patch_make("XY", "XtestY"); + assertEquals("patch_addPadding: Both edges partial.", "@@ -1,2 +1,6 @@\n X\n+test\n Y\n", dmp.patch_toText(patches)); + dmp.patch_addPadding(patches); + assertEquals("patch_addPadding: Both edges partial.", "@@ -2,8 +2,12 @@\n %02%03%04X\n+test\n Y%01%02%03\n", dmp.patch_toText(patches)); + + patches = dmp.patch_make("XXXXYYYY", "XXXXtestYYYY"); + assertEquals("patch_addPadding: Both edges none.", "@@ -1,8 +1,12 @@\n XXXX\n+test\n YYYY\n", dmp.patch_toText(patches)); + dmp.patch_addPadding(patches); + assertEquals("patch_addPadding: Both edges none.", "@@ -5,8 +5,12 @@\n XXXX\n+test\n YYYY\n", dmp.patch_toText(patches)); + } + + public void testPatchApply() { + dmp.Match_Distance = 1000; + dmp.Match_Threshold = 0.5f; + dmp.Patch_DeleteThreshold = 0.5f; + LinkedList patches; + patches = dmp.patch_make("The quick brown fox jumps over the lazy dog.", "That quick brown fox jumped over a lazy dog."); + Object[] results = dmp.patch_apply(patches, "The quick brown fox jumps over the lazy dog."); + boolean[] boolArray = (boolean[]) results[1]; + String resultStr = results[0] + "\t" + boolArray[0] + "\t" + boolArray[1]; + assertEquals("patch_apply: Exact match.", "That quick brown fox jumped over a lazy dog.\ttrue\ttrue", resultStr); + + results = dmp.patch_apply(patches, "The quick red rabbit jumps over the tired tiger."); + boolArray = (boolean[]) results[1]; + resultStr = results[0] + "\t" + boolArray[0] + "\t" + boolArray[1]; + assertEquals("patch_apply: Partial match.", "That quick red rabbit jumped over a tired tiger.\ttrue\ttrue", resultStr); + + results = dmp.patch_apply(patches, "I am the very model of a modern major general."); + boolArray = (boolean[]) results[1]; + resultStr = results[0] + "\t" + boolArray[0] + "\t" + boolArray[1]; + assertEquals("patch_apply: Failed match.", "I am the very model of a modern major general.\tfalse\tfalse", resultStr); + + patches = dmp.patch_make("x1234567890123456789012345678901234567890123456789012345678901234567890y", "xabcy"); + results = dmp.patch_apply(patches, "x123456789012345678901234567890-----++++++++++-----123456789012345678901234567890y"); + boolArray = (boolean[]) results[1]; + resultStr = results[0] + "\t" + boolArray[0] + "\t" + boolArray[1]; + assertEquals("patch_apply: Big delete, small change.", "xabcy\ttrue\ttrue", resultStr); + + patches = dmp.patch_make("x1234567890123456789012345678901234567890123456789012345678901234567890y", "xabcy"); + results = dmp.patch_apply(patches, "x12345678901234567890---------------++++++++++---------------12345678901234567890y"); + boolArray = (boolean[]) results[1]; + resultStr = results[0] + "\t" + boolArray[0] + "\t" + boolArray[1]; + assertEquals("patch_apply: Big delete, big change 1.", "xabc12345678901234567890---------------++++++++++---------------12345678901234567890y\tfalse\ttrue", resultStr); + + dmp.Patch_DeleteThreshold = 0.6f; + patches = dmp.patch_make("x1234567890123456789012345678901234567890123456789012345678901234567890y", "xabcy"); + results = dmp.patch_apply(patches, "x12345678901234567890---------------++++++++++---------------12345678901234567890y"); + boolArray = (boolean[]) results[1]; + resultStr = results[0] + "\t" + boolArray[0] + "\t" + boolArray[1]; + assertEquals("patch_apply: Big delete, big change 2.", "xabcy\ttrue\ttrue", resultStr); + dmp.Patch_DeleteThreshold = 0.5f; + + // Compensate for failed patch. + dmp.Match_Threshold = 0.0f; + dmp.Match_Distance = 0; + patches = dmp.patch_make("abcdefghijklmnopqrstuvwxyz--------------------1234567890", "abcXXXXXXXXXXdefghijklmnopqrstuvwxyz--------------------1234567YYYYYYYYYY890"); + results = dmp.patch_apply(patches, "ABCDEFGHIJKLMNOPQRSTUVWXYZ--------------------1234567890"); + boolArray = (boolean[]) results[1]; + resultStr = results[0] + "\t" + boolArray[0] + "\t" + boolArray[1]; + assertEquals("ABCDEFGHIJKLMNOPQRSTUVWXYZ--------------------1234567YYYYYYYYYY890\tfalse\ttrue", resultStr); + dmp.Match_Threshold = 0.5f; + dmp.Match_Distance = 1000; + + patches = dmp.patch_make("", "test"); + String patchStr = dmp.patch_toText(patches); + dmp.patch_apply(patches, ""); + assertEquals("patch_apply: No side effects.", patchStr, dmp.patch_toText(patches)); + + patches = dmp.patch_make("The quick brown fox jumps over the lazy dog.", "Woof"); + patchStr = dmp.patch_toText(patches); + dmp.patch_apply(patches, "The quick brown fox jumps over the lazy dog."); + assertEquals("patch_apply: No side effects with major delete.", patchStr, dmp.patch_toText(patches)); + + patches = dmp.patch_make("", "test"); + results = dmp.patch_apply(patches, ""); + boolArray = (boolean[]) results[1]; + resultStr = results[0] + "\t" + boolArray[0]; + assertEquals("patch_apply: Edge exact match.", "test\ttrue", resultStr); + + patches = dmp.patch_make("XY", "XtestY"); + results = dmp.patch_apply(patches, "XY"); + boolArray = (boolean[]) results[1]; + resultStr = results[0] + "\t" + boolArray[0]; + assertEquals("patch_apply: Near edge exact match.", "XtestY\ttrue", resultStr); + + patches = dmp.patch_make("y", "y123"); + results = dmp.patch_apply(patches, "x"); + boolArray = (boolean[]) results[1]; + resultStr = results[0] + "\t" + boolArray[0]; + assertEquals("patch_apply: Edge partial match.", "x123\ttrue", resultStr); + } + + + private void assertArrayEquals(String error_msg, Object[] a, Object[] b) { + List list_a = Arrays.asList(a); + List list_b = Arrays.asList(b); + assertEquals(error_msg, list_a, list_b); + } + + + private void assertLinesToCharsResultEquals(String error_msg, + LinesToCharsResult a, LinesToCharsResult b) { + assertEquals(error_msg, a.chars1, b.chars1); + assertEquals(error_msg, a.chars2, b.chars2); + assertEquals(error_msg, a.lineArray, b.lineArray); + } + + // Construct the two texts which made up the diff originally. + private static String[] diff_rebuildtexts(LinkedList diffs) { + String[] text = {"", ""}; + for (Diff myDiff : diffs) { + if (myDiff.operation != diff_match_patch.Operation.INSERT) { + text[0] += myDiff.text; + } + if (myDiff.operation != diff_match_patch.Operation.DELETE) { + text[1] += myDiff.text; + } + } + return text; + } + + + // Private function for quickly building lists of diffs. + private static LinkedList diffList(Diff... diffs) { + LinkedList myDiffList = new LinkedList(); + for (Diff myDiff : diffs) { + myDiffList.add(myDiff); + } + return myDiffList; + } +} -- cgit v1.2.3