1 files changed, 35 insertions, 0 deletions
diff --git a/lib/private/util.bzl b/lib/private/util.bzl
new file mode 100644
index 0000000..fc003f9
--- /dev/null
+++ b/lib/private/util.bzl
@@ -0,0 +1,35 @@
+"""Shared private utilities."""
+
+def _do_nothing_impl(ctx):
+    _ = ctx  # @unused
+    return []
+
+do_nothing = rule(implementation = _do_nothing_impl)
+
+def get_test_name_from_function(func):
+    """Derives a suitable test name from a function.
+
+    This can be used for better test feedback.
+
+    Args:
+      func: (callable) A test implementation or setup function.
+
+    Returns:
+      (str) The name of the given function, suitable as a test name.
+    """
+
+    # Starlark currently stringifies a function as "<function NAME>", so we use
+    # that knowledge to parse the "NAME" portion out. If this behavior ever
+    # changes, we'll need to update this.
+    # TODO(bazel-team): Expose a ._name field on functions to avoid this.
+    func_name = str(func)
+    func_name = func_name.partition("<function ")[-1]
+    func_name = func_name.rpartition(">")[0]
+    func_name = func_name.partition(" ")[0]
+
+    # Strip leading/trailing underscores so that test functions can
+    # have private names. This better allows unused tests to be flagged by
+    # buildifier (indicating a bug or code to delete)
+    return func_name.strip("_")
+
+get_function_name = get_test_name_from_function