1 files changed, 146 insertions, 0 deletions
diff --git a/src/test/java/com/code_intelligence/jazzer/mutation/support/InputStreamSupportTest.java b/src/test/java/com/code_intelligence/jazzer/mutation/support/InputStreamSupportTest.java
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+/*
+ * Copyright 2023 Code Intelligence GmbH
+ *
+ * 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 com.code_intelligence.jazzer.mutation.support;
+
+import static com.code_intelligence.jazzer.mutation.support.InputStreamSupport.cap;
+import static com.code_intelligence.jazzer.mutation.support.InputStreamSupport.extendWithReadExactly;
+import static com.code_intelligence.jazzer.mutation.support.InputStreamSupport.extendWithZeros;
+import static com.code_intelligence.jazzer.mutation.support.InputStreamSupport.infiniteZeros;
+import static com.code_intelligence.jazzer.mutation.support.InputStreamSupport.readAllBytes;
+import static com.google.common.truth.Truth.assertThat;
+
+import com.code_intelligence.jazzer.mutation.support.InputStreamSupport.ReadExactlyInputStream;
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+class InputStreamSupportTest {
+  @Test
+  void testInfiniteZeros() throws IOException {
+    InputStream input = infiniteZeros();
+
+    assertThat(input.available()).isEqualTo(Integer.MAX_VALUE);
+    assertThat(input.read()).isEqualTo(0);
+
+    input.close();
+
+    assertThat(input.available()).isEqualTo(Integer.MAX_VALUE);
+    assertThat(input.read()).isEqualTo(0);
+  }
+
+  @Test
+  void testExtendWithNullInputStream_empty() throws IOException {
+    InputStream input = extendWithZeros(new ByteArrayInputStream(new byte[0]));
+    assertThat(input.skip(5)).isEqualTo(5);
+    assertThat(input.read()).isEqualTo(0);
+    byte[] bytes = new byte[] {9, 9, 9, 9, 9};
+    assertThat(input.read(bytes)).isEqualTo(5);
+    assertThat(bytes).asList().containsExactly((byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0);
+  }
+
+  @Test
+  void testExtendWithNullInputStream_emptyAfterRead() throws IOException {
+    InputStream input = extendWithZeros(new ByteArrayInputStream(new byte[] {1}));
+    assertThat(input.read()).isEqualTo(1);
+    assertThat(input.read()).isEqualTo(0);
+    assertThat(input.read()).isEqualTo(0);
+    byte[] bytes = new byte[] {9, 9, 9, 9, 9};
+    assertThat(input.read(bytes)).isEqualTo(5);
+    assertThat(bytes).asList().containsExactly((byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0);
+  }
+
+  @Test
+  void testExtendWithNullInputStream_emptyWithinRead() throws IOException {
+    InputStream input = extendWithZeros(new ByteArrayInputStream(new byte[] {1, 2, 3}));
+    byte[] bytes = new byte[] {9, 9, 9, 9, 9};
+    assertThat(input.read(bytes)).isEqualTo(5);
+    assertThat(bytes).asList().containsExactly((byte) 1, (byte) 2, (byte) 3, (byte) 0, (byte) 0);
+  }
+
+  @Test
+  void testExtendWithNullInputStream_emptyWithinSkip() throws IOException {
+    InputStream input = extendWithZeros(new ByteArrayInputStream(new byte[] {1, 2, 3}));
+    assertThat(input.skip(5)).isEqualTo(5);
+    byte[] bytes = new byte[] {9, 9, 9, 9, 9};
+    assertThat(input.read(bytes)).isEqualTo(5);
+    assertThat(bytes).asList().containsExactly((byte) 0, (byte) 0, (byte) 0, (byte) 0, (byte) 0);
+  }
+
+  @Test
+  void testCap_reachedAfterRead() throws IOException {
+    InputStream input = cap(new ByteArrayInputStream(new byte[] {1, 2, 3, 4, 5}), 3);
+    assertThat(input.available()).isEqualTo(3);
+    assertThat(input.read()).isEqualTo(1);
+    assertThat(input.available()).isEqualTo(2);
+    assertThat(input.read()).isEqualTo(2);
+    assertThat(input.available()).isEqualTo(1);
+    assertThat(input.read()).isEqualTo(3);
+    assertThat(input.available()).isEqualTo(0);
+    assertThat(input.read()).isEqualTo(-1);
+    assertThat(input.read(new byte[5], 0, 5)).isEqualTo(-1);
+  }
+
+  @Test
+  void testCap_reachedWithinRead() throws IOException {
+    InputStream input = cap(new ByteArrayInputStream(new byte[] {1, 2, 3, 4, 5}), 3);
+    byte[] bytes = new byte[5];
+    assertThat(input.available()).isEqualTo(3);
+    assertThat(input.read(bytes, 0, 5)).isEqualTo(3);
+    assertThat(bytes).asList().containsExactly((byte) 1, (byte) 2, (byte) 3, (byte) 0, (byte) 0);
+  }
+
+  @ParameterizedTest
+  // 8192 is the internal buffer size.
+  @ValueSource(ints = {0, 1, 3, 500, 8192, 8192 + 17, 8192 * 8192 + 17})
+  void testReadAllBytes(int length) throws IOException {
+    byte[] bytes = new byte[length];
+    for (int i = 0; i < bytes.length; i++) {
+      bytes[i] = (byte) i;
+    }
+    InputStream input = new ByteArrayInputStream(bytes);
+
+    assertThat(readAllBytes(input)).isEqualTo(bytes);
+  }
+
+  @Test
+  @SuppressWarnings("ResultOfMethodCallIgnored")
+  void testReadExactly() throws IOException {
+    ReadExactlyInputStream ce = extendWithReadExactly(new ByteArrayInputStream(new byte[] {0, 1}));
+    assertThat(ce.isConsumedExactly()).isFalse();
+    ce.read();
+    assertThat(ce.isConsumedExactly()).isFalse();
+    ce.read();
+    assertThat(ce.isConsumedExactly()).isTrue();
+    ce.read();
+    assertThat(ce.isConsumedExactly()).isFalse();
+  }
+
+  @Test
+  @SuppressWarnings("ResultOfMethodCallIgnored")
+  void testReadExactly_readBytes() throws IOException {
+    ReadExactlyInputStream ce =
+        extendWithReadExactly(new ByteArrayInputStream(new byte[] {0, 1, 2}));
+    assertThat(ce.isConsumedExactly()).isFalse();
+    ce.read(new byte[3]);
+    assertThat(ce.isConsumedExactly()).isTrue();
+    ce.read(new byte[1]);
+    assertThat(ce.isConsumedExactly()).isFalse();
+  }
+}