public void diff_cleanupMergeTest() {
diff_match_patchTest dmp = new diff_match_patchTest();
// Cleanup a messy diff.
// Null case.
List<Diff> diffs = new List<Diff>();
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff>(), diffs);
// No change case.
diffs = new List<Diff> {new Diff(Operation.EQUAL, "a"), new Diff(Operation.DELETE, "b"), new Diff(Operation.INSERT, "c")};
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff> {new Diff(Operation.EQUAL, "a"), new Diff(Operation.DELETE, "b"), new Diff(Operation.INSERT, "c")}, diffs);
// Merge equalities.
diffs = new List<Diff> {new Diff(Operation.EQUAL, "a"), new Diff(Operation.EQUAL, "b"), new Diff(Operation.EQUAL, "c")};
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff> {new Diff(Operation.EQUAL, "abc")}, diffs);
// Merge deletions.
diffs = new List<Diff> {new Diff(Operation.DELETE, "a"), new Diff(Operation.DELETE, "b"), new Diff(Operation.DELETE, "c")};
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff> {new Diff(Operation.DELETE, "abc")}, diffs);
// Merge insertions.
diffs = new List<Diff> {new Diff(Operation.INSERT, "a"), new Diff(Operation.INSERT, "b"), new Diff(Operation.INSERT, "c")};
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff> {new Diff(Operation.INSERT, "abc")}, diffs);
// Merge interweave.
diffs = new List<Diff> {new Diff(Operation.DELETE, "a"), new Diff(Operation.INSERT, "b"), new Diff(Operation.DELETE, "c"), new Diff(Operation.INSERT, "d"), new Diff(Operation.EQUAL, "e"), new Diff(Operation.EQUAL, "f")};
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff> {new Diff(Operation.DELETE, "ac"), new Diff(Operation.INSERT, "bd"), new Diff(Operation.EQUAL, "ef")}, diffs);
// Prefix and suffix detection.
diffs = new List<Diff> {new Diff(Operation.DELETE, "a"), new Diff(Operation.INSERT, "abc"), new Diff(Operation.DELETE, "dc")};
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff> {new Diff(Operation.EQUAL, "a"), new Diff(Operation.DELETE, "d"), new Diff(Operation.INSERT, "b"), new Diff(Operation.EQUAL, "c")}, diffs);
// Prefix and suffix detection with equalities.
diffs = new List<Diff> {new Diff(Operation.EQUAL, "x"), new Diff(Operation.DELETE, "a"), new Diff(Operation.INSERT, "abc"), new Diff(Operation.DELETE, "dc"), new Diff(Operation.EQUAL, "y")};
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff> {new Diff(Operation.EQUAL, "xa"), new Diff(Operation.DELETE, "d"), new Diff(Operation.INSERT, "b"), new Diff(Operation.EQUAL, "cy")}, diffs);
// Slide edit left.
diffs = new List<Diff> {new Diff(Operation.EQUAL, "a"), new Diff(Operation.INSERT, "ba"), new Diff(Operation.EQUAL, "c")};
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff> {new Diff(Operation.INSERT, "ab"), new Diff(Operation.EQUAL, "ac")}, diffs);
// Slide edit right.
diffs = new List<Diff> {new Diff(Operation.EQUAL, "c"), new Diff(Operation.INSERT, "ab"), new Diff(Operation.EQUAL, "a")};
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff> {new Diff(Operation.EQUAL, "ca"), new Diff(Operation.INSERT, "ba")}, diffs);
// Slide edit left recursive.
diffs = new List<Diff> {new Diff(Operation.EQUAL, "a"), new Diff(Operation.DELETE, "b"), new Diff(Operation.EQUAL, "c"), new Diff(Operation.DELETE, "ac"), new Diff(Operation.EQUAL, "x")};
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff> {new Diff(Operation.DELETE, "abc"), new Diff(Operation.EQUAL, "acx")}, diffs);
// Slide edit right recursive.
diffs = new List<Diff> {new Diff(Operation.EQUAL, "x"), new Diff(Operation.DELETE, "ca"), new Diff(Operation.EQUAL, "c"), new Diff(Operation.DELETE, "b"), new Diff(Operation.EQUAL, "a")};
dmp.diff_cleanupMerge(diffs);
CollectionAssert.AreEqual(new List<Diff> {new Diff(Operation.EQUAL, "xca"), new Diff(Operation.DELETE, "cba")}, diffs);
}