Initial implementation of diff rename detection

This implements the basis for diff rename and copy detection,
although it is based on simple SHA comparison right now instead
of using a matching algortihm.  Just as `git_diff_merge` can be
used as a post-pass on diffs to emulate certain command line
behaviors, there is a new API `git_diff_detect` which will
update a diff list in-place, adjusting some deltas to RENAMED
or COPIED state (and also, eventually, splitting MODIFIED deltas
where the change is too large into DELETED/ADDED pairs).

This also adds a new test repo that will hold rename/copy/split
scenarios.  Right now, it just has exact-match rename and copy,
but the tests are written to use tree diffs, so we should be able
to add new test scenarios easily without breaking tests.

1 files changed, 25 insertions, 25 deletions

diff --git a/tests-clar/diff/tree.c b/tests-clar/diff/tree.c
index c5a0e626e..f8b9a71a5 100644
--- a/tests-clar/diff/tree.c
+++ b/tests-clar/diff/tree.c
@@ -40,9 +40,9 @@ void test_diff_tree__0(void)
 		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(5, exp.files);
-	cl_assert_equal_i(2, exp.file_adds);
-	cl_assert_equal_i(1, exp.file_dels);
-	cl_assert_equal_i(2, exp.file_mods);
+	cl_assert_equal_i(2, exp.file_status[GIT_DELTA_ADDED]);
+	cl_assert_equal_i(1, exp.file_status[GIT_DELTA_DELETED]);
+	cl_assert_equal_i(2, exp.file_status[GIT_DELTA_MODIFIED]);
 
 	cl_assert_equal_i(5, exp.hunks);
 
@@ -62,9 +62,9 @@ void test_diff_tree__0(void)
 		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(2, exp.files);
-	cl_assert_equal_i(0, exp.file_adds);
-	cl_assert_equal_i(0, exp.file_dels);
-	cl_assert_equal_i(2, exp.file_mods);
+	cl_assert_equal_i(0, exp.file_status[GIT_DELTA_ADDED]);
+	cl_assert_equal_i(0, exp.file_status[GIT_DELTA_DELETED]);
+	cl_assert_equal_i(2, exp.file_status[GIT_DELTA_MODIFIED]);
 
 	cl_assert_equal_i(2, exp.hunks);
 
@@ -111,22 +111,23 @@ void test_diff_tree__options(void)
 	 * - git diff [options] 6bab5c79cd5140d0 605812ab7fe421fdd
 	 * - mv .git .gitted
 	 */
+#define EXPECT_STATUS_ADM(ADDS,DELS,MODS) { 0, ADDS, DELS, MODS, 0, 0, 0, 0, 0 }
 	diff_expects test_expects[] = {
 		/* a vs b tests */
-		{ 5, 0, 3, 0, 2, 0, 0, 0, 4, 0, 0, 51, 2, 46, 3 },
-		{ 5, 0, 3, 0, 2, 0, 0, 0, 4, 0, 0, 53, 4, 46, 3 },
-		{ 5, 0, 0, 3, 2, 0, 0, 0, 4, 0, 0, 52, 3, 3, 46 },
-		{ 5, 0, 3, 0, 2, 0, 0, 0, 5, 0, 0, 54, 3, 47, 4 },
+		{ 5, 0, EXPECT_STATUS_ADM(3, 0, 2), 4, 0, 0, 51, 2, 46, 3 },
+		{ 5, 0, EXPECT_STATUS_ADM(3, 0, 2), 4, 0, 0, 53, 4, 46, 3 },
+		{ 5, 0, EXPECT_STATUS_ADM(0, 3, 2), 4, 0, 0, 52, 3, 3, 46 },
+		{ 5, 0, EXPECT_STATUS_ADM(3, 0, 2), 5, 0, 0, 54, 3, 47, 4 },
 		/* c vs d tests */
-		{ 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 22, 9, 10, 3 },
-		{ 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 19, 12, 7, 0 },
-		{ 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 20, 11, 8, 1 },
-		{ 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 20, 11, 8, 1 },
-		{ 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 18, 11, 0, 7 },
+		{ 1, 0, EXPECT_STATUS_ADM(0, 0, 1), 1, 0, 0, 22, 9, 10, 3 },
+		{ 1, 0, EXPECT_STATUS_ADM(0, 0, 1), 1, 0, 0, 19, 12, 7, 0 },
+		{ 1, 0, EXPECT_STATUS_ADM(0, 0, 1), 1, 0, 0, 20, 11, 8, 1 },
+		{ 1, 0, EXPECT_STATUS_ADM(0, 0, 1), 1, 0, 0, 20, 11, 8, 1 },
+		{ 1, 0, EXPECT_STATUS_ADM(0, 0, 1), 1, 0, 0, 18, 11, 0, 7 },
 		{ 0 },
 	};
 	diff_expects *expected;
-	int i;
+	int i, j;
 
 	g_repo = cl_git_sandbox_init("attr");
 
@@ -149,9 +150,8 @@ void test_diff_tree__options(void)
 
 		expected = &test_expects[i];
 		cl_assert_equal_i(actual.files,     expected->files);
-		cl_assert_equal_i(actual.file_adds, expected->file_adds);
- 		cl_assert_equal_i(actual.file_dels, expected->file_dels);
-		cl_assert_equal_i(actual.file_mods, expected->file_mods);
+		for (j = GIT_DELTA_UNMODIFIED; j <= GIT_DELTA_TYPECHANGE; ++j)
+			cl_assert_equal_i(expected->file_status[j], actual.file_status[j]);
 		cl_assert_equal_i(actual.hunks,     expected->hunks);
 		cl_assert_equal_i(actual.lines,     expected->lines);
 		cl_assert_equal_i(actual.line_ctxt, expected->line_ctxt);
@@ -193,9 +193,9 @@ void test_diff_tree__bare(void)
 		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(3, exp.files);
-	cl_assert_equal_i(2, exp.file_adds);
-	cl_assert_equal_i(0, exp.file_dels);
-	cl_assert_equal_i(1, exp.file_mods);
+	cl_assert_equal_i(2, exp.file_status[GIT_DELTA_ADDED]);
+	cl_assert_equal_i(0, exp.file_status[GIT_DELTA_DELETED]);
+	cl_assert_equal_i(1, exp.file_status[GIT_DELTA_MODIFIED]);
 
 	cl_assert_equal_i(3, exp.hunks);
 
@@ -243,9 +243,9 @@ void test_diff_tree__merge(void)
 		diff1, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(6, exp.files);
-	cl_assert_equal_i(2, exp.file_adds);
-	cl_assert_equal_i(1, exp.file_dels);
-	cl_assert_equal_i(3, exp.file_mods);
+	cl_assert_equal_i(2, exp.file_status[GIT_DELTA_ADDED]);
+	cl_assert_equal_i(1, exp.file_status[GIT_DELTA_DELETED]);
+	cl_assert_equal_i(3, exp.file_status[GIT_DELTA_MODIFIED]);
 
 	cl_assert_equal_i(6, exp.hunks);