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.

28 files changed, 589 insertions, 166 deletions

diff --git a/include/git2/diff.h b/include/git2/diff.h
index 1932db029..f9dbb67e0 100644
--- a/include/git2/diff.h
+++ b/include/git2/diff.h
@@ -33,7 +33,7 @@ GIT_BEGIN_DECL
  * Flags for diff options.  A combination of these flags can be passed
  * in via the `flags` value in the `git_diff_options`.
  */
-enum {
+typedef enum {
 	/** Normal diff, the default */
 	GIT_DIFF_NORMAL = 0,
 	/** Reverse the sides of the diff */
@@ -86,7 +86,7 @@ enum {
 	 *  mode set to tree.  Note: the tree SHA will not be available.
 	 */
 	GIT_DIFF_INCLUDE_TYPECHANGE_TREES  = (1 << 16),
-};
+} git_diff_option_t;
 
 /**
  * Structure describing options about how the diff should be executed.
@@ -95,7 +95,7 @@ enum {
  * values.  Similarly, passing NULL for the options structure will
  * give the defaults.  The default values are marked below.
  *
- * - flags: a combination of the GIT_DIFF_... values above
+ * - flags: a combination of the git_diff_option_t values above
  * - context_lines: number of lines of context to show around diffs
  * - interhunk_lines: min lines between diff hunks to merge them
  * - old_prefix: "directory" to prefix to old file names (default "a")
@@ -124,7 +124,7 @@ typedef struct git_diff_list git_diff_list;
  * Most of the flags are just for internal consumption by libgit2,
  * but some of them may be interesting to external users.
  */
-enum {
+typedef enum {
 	GIT_DIFF_FILE_VALID_OID  = (1 << 0), /** `oid` value is known correct */
 	GIT_DIFF_FILE_FREE_PATH  = (1 << 1), /** `path` is allocated memory */
 	GIT_DIFF_FILE_BINARY     = (1 << 2), /** should be considered binary data */
@@ -132,7 +132,7 @@ enum {
 	GIT_DIFF_FILE_FREE_DATA  = (1 << 4), /** internal file data is allocated */
 	GIT_DIFF_FILE_UNMAP_DATA = (1 << 5), /** internal file data is mmap'ed */
 	GIT_DIFF_FILE_NO_DATA    = (1 << 6), /** file data should not be loaded */
-};
+} git_diff_file_flag_t;
 
 /**
  * What type of change is described by a git_diff_delta?
@@ -218,7 +218,7 @@ typedef int (*git_diff_hunk_fn)(
  * output callbacks to demarcate lines that are actually part of
  * the file or hunk headers.
  */
-enum {
+typedef enum {
 	/* These values will be sent to `git_diff_data_fn` along with the line */
 	GIT_DIFF_LINE_CONTEXT   = ' ',
 	GIT_DIFF_LINE_ADDITION  = '+',
@@ -233,7 +233,7 @@ enum {
 	GIT_DIFF_LINE_FILE_HDR  = 'F',
 	GIT_DIFF_LINE_HUNK_HDR  = 'H',
 	GIT_DIFF_LINE_BINARY    = 'B'
-};
+} git_diff_line_t;
 
 /**
  * When iterating over a diff, callback that will be made per text diff
@@ -259,6 +259,36 @@ typedef int (*git_diff_data_fn)(
  */
 typedef struct git_diff_patch git_diff_patch;
 
+/**
+ * Flags to control the behavior of diff rename/copy detection.
+ */
+typedef enum {
+	/** should we look for renames */
+	GIT_DIFF_DETECT_RENAMES = (1 << 0),
+	/** should we look for copies */
+	GIT_DIFF_DETECT_COPIES   = (1 << 1),
+	/** should we consider unmodified files as possible copy sources */
+	GIT_DIFF_DETECT_COPIES_FROM_UNMODIFIED = (1 << 2),
+	/** should we split large rewrites into delete / add pairs */
+	GIT_DIFF_DETECT_BREAK_REWRITES = (1 << 3),
+} git_diff_detect_t;
+
+/**
+ * Control behavior of rename and copy detection
+ */
+typedef struct {
+	/** Combination of git_diff_detect_t values */
+	unsigned int flags;
+	/** Threshold on similarity index to consider a file renamed. */
+	unsigned int rename_threshold;
+	/** Threshold on similarity index to consider a file a copy. */
+	unsigned int copy_threshold;
+	/** Threshold on change % to split modify into delete/add pair. */
+	unsigned int break_rewrite_threshold;
+	/** Maximum rename/copy targets to check (diff.renameLimit) */
+	unsigned int target_limit;
+} git_diff_detect_options;
+
 
 /** @name Diff List Generator Functions
  *
@@ -374,6 +404,20 @@ GIT_EXTERN(int) git_diff_merge(
 	git_diff_list *onto,
 	const git_diff_list *from);
 
+/**
+ * Update a diff list with file renames, copies, etc.
+ *
+ * This modifies a diff list in place, replacing old entries that look
+ * like renames or copies with new entries reflecting those changes.
+ *
+ * @param diff Diff list to run detection algorithms on
+ * @param options Control how detection should be run, NULL for defaults
+ * @return 0 on success, -1 on failure
+ */
+GIT_EXTERN(int) git_diff_detect(
+	git_diff_list *diff,
+	git_diff_detect_options *options);
+
 /**@}*/
 
 
diff --git a/src/diff.c b/src/diff.c
index 9f693bebf..e2649ff3b 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -378,12 +378,23 @@ static git_diff_list *git_diff_list_alloc(
 		diff->diffcaps = diff->diffcaps | GIT_DIFFCAPS_TRUST_CTIME;
 	/* Don't set GIT_DIFFCAPS_USE_DEV - compile time option in core git */
 
+	/* TODO: there are certain config settings where even if we were
+	 * not given an options structure, we need the diff list to have one
+	 * so that we can store the altered default values.
+	 *
+	 * - diff.ignoreSubmodules
+	 * - diff.mnemonicprefix
+	 * - diff.noprefix
+	 */
+
 	if (opts == NULL)
 		return diff;
 
 	memcpy(&diff->opts, opts, sizeof(git_diff_options));
 	memset(&diff->opts.pathspec, 0, sizeof(diff->opts.pathspec));
 
+	/* TODO: handle config diff.mnemonicprefix, diff.noprefix */
+
 	diff->opts.old_prefix = diff_strdup_prefix(&diff->pool,
 		opts->old_prefix ? opts->old_prefix : DIFF_OLD_PREFIX_DEFAULT);
 	diff->opts.new_prefix = diff_strdup_prefix(&diff->pool,
@@ -1082,3 +1093,139 @@ int git_diff_merge(
 
 	return error;
 }
+
+#define DEFAULT_THRESHOLD 50
+#define DEFAULT_TARGET_LIMIT 200
+
+int git_diff_detect(
+	git_diff_list *diff,
+	git_diff_detect_options *opts)
+{
+	int error = 0;
+	unsigned int i, j;
+	git_diff_delta *from, *to;
+	bool check_unmodified = opts &&
+		(opts->flags & GIT_DIFF_DETECT_COPIES_FROM_UNMODIFIED) != 0;
+	int max_targets = (opts && opts->target_limit > 0) ?
+		opts->target_limit : DEFAULT_TARGET_LIMIT;
+	unsigned int rename_threshold = (opts && opts->rename_threshold > 0) ?
+		opts->rename_threshold : DEFAULT_THRESHOLD;
+	unsigned int copy_threshold = (opts && opts->copy_threshold > 0) ?
+		opts->copy_threshold : DEFAULT_THRESHOLD;
+	int num_deletes = 0, num_splits = 0;
+
+	/* TODO: update opts from config diff.renameLimit / diff.renames */
+
+	git_vector_foreach(&diff->deltas, i, from) {
+		int tried_targets = 0;
+
+		git_vector_foreach(&diff->deltas, j, to) {
+			unsigned int similarity = 0;
+
+			if (i == j)
+				continue;
+
+			switch (to->status) {
+			case GIT_DELTA_ADDED:
+			case GIT_DELTA_UNTRACKED:
+			case GIT_DELTA_RENAMED:
+			case GIT_DELTA_COPIED:
+				break;
+			default:
+				/* only those status values should be checked */
+				continue;
+			}
+
+			/* don't check UNMODIFIED files as source unless given option */
+			if (from->status == GIT_DELTA_UNMODIFIED && !check_unmodified)
+				continue;
+
+			/* cap on maximum files we'll examine */
+			if (++tried_targets > max_targets)
+				break;
+
+			/* calculate similarity and see if this pair beats the
+			 * similarity score of the current best pair.
+			 */
+			if (git_oid_cmp(&from->old_file.oid, &to->new_file.oid) == 0)
+				similarity = 100;
+			/* TODO: insert actual similarity algo here */
+
+			if (similarity <= to->similarity)
+				continue;
+
+			if (from->status == GIT_DELTA_DELETED) {
+				if (similarity < rename_threshold)
+					continue;
+
+				/* merge "from" & "to" to a RENAMED record */
+				to->status = GIT_DELTA_RENAMED;
+				memcpy(&to->old_file, &from->old_file, sizeof(to->old_file));
+
+				from->status = GIT_DELTA__TO_DELETE;
+				num_deletes++;
+			} else {
+				if (similarity < copy_threshold)
+					continue;
+
+				/* convert "to" to a COPIED record */
+				to->status = GIT_DELTA_COPIED;
+				memcpy(&to->old_file, &from->old_file, sizeof(to->old_file));
+			}
+		}
+
+		if (from->status == GIT_DELTA_MODIFIED &&
+			opts && (opts->flags & GIT_DIFF_DETECT_BREAK_REWRITES) != 0)
+		{
+			/* TODO: calculate similarity and maybe mark for split */
+
+			/* from->status = GIT_DELTA__TO_SPLIT; */
+			/* num_splits++; */
+		}
+	}
+
+	if (num_deletes > 0 || num_splits > 0) {
+		git_vector onto = GIT_VECTOR_INIT;
+		size_t new_size = diff->deltas.length + num_splits - num_deletes;
+
+		if (git_vector_init(&onto, new_size, diff_delta__cmp) < 0)
+			return -1;
+
+		/* build new delta list without TO_DELETE and splitting TO_SPLIT */
+		git_vector_foreach(&diff->deltas, i, from) {
+			if (from->status == GIT_DELTA__TO_DELETE) {
+				git__free(from);
+				continue;
+			}
+
+			if (from->status == GIT_DELTA__TO_SPLIT) {
+				git_diff_delta *deleted = diff_delta__dup(from, &diff->pool);
+				if (!deleted)
+					return -1;
+
+				deleted->status = GIT_DELTA_DELETED;
+				memset(&deleted->new_file, 0, sizeof(deleted->new_file));
+				deleted->new_file.path = deleted->old_file.path;
+				deleted->new_file.flags |= GIT_DIFF_FILE_VALID_OID;
+
+				git_vector_insert(&onto, deleted);
+
+				from->status = GIT_DELTA_ADDED;
+				memset(&from->old_file, 0, sizeof(from->old_file));
+				from->old_file.path = from->new_file.path;
+				from->old_file.flags |= GIT_DIFF_FILE_VALID_OID;
+			}
+
+			git_vector_insert(&onto, from);
+		}
+
+		/* swap new delta list into place */
+
+		git_vector_sort(&onto);
+		git_vector_swap(&diff->deltas, &onto);
+		git_vector_free(&onto);
+	}
+
+	return error;
+}
+
diff --git a/src/diff.h b/src/diff.h
index c6a26aee7..61723bc9e 100644
--- a/src/diff.h
+++ b/src/diff.h
@@ -28,6 +28,9 @@ enum {
 	GIT_DIFFCAPS_USE_DEV          = (1 << 4), /* use st_dev? */
 };
 
+#define GIT_DELTA__TO_DELETE 10
+#define GIT_DELTA__TO_SPLIT  11
+
 struct git_diff_list {
 	git_refcount     rc;
 	git_repository   *repo;
diff --git a/tests-clar/diff/blob.c b/tests-clar/diff/blob.c
index d5cf41e99..0a37e829d 100644
--- a/tests-clar/diff/blob.c
+++ b/tests-clar/diff/blob.c
@@ -59,8 +59,8 @@ void test_diff_blob__can_compare_text_blobs(void)
 		a, b, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(1, expected.files);
-	cl_assert_equal_i(1, expected.file_mods);
-	cl_assert(expected.at_least_one_of_them_is_binary == false);
+	cl_assert_equal_i(1, expected.file_status[GIT_DELTA_MODIFIED]);
+	cl_assert_equal_i(0, expected.files_binary);
 
 	cl_assert_equal_i(1, expected.hunks);
 	cl_assert_equal_i(6, expected.lines);
@@ -74,8 +74,8 @@ void test_diff_blob__can_compare_text_blobs(void)
 		b, c, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(1, expected.files);
-	cl_assert_equal_i(1, expected.file_mods);
-	cl_assert(expected.at_least_one_of_them_is_binary == false);
+	cl_assert_equal_i(1, expected.file_status[GIT_DELTA_MODIFIED]);
+	cl_assert_equal_i(0, expected.files_binary);
 
 	cl_assert_equal_i(1, expected.hunks);
 	cl_assert_equal_i(15, expected.lines);
@@ -89,8 +89,8 @@ void test_diff_blob__can_compare_text_blobs(void)
 		a, c, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(1, expected.files);
-	cl_assert_equal_i(1, expected.file_mods);
-	cl_assert(expected.at_least_one_of_them_is_binary == false);
+	cl_assert_equal_i(1, expected.file_status[GIT_DELTA_MODIFIED]);
+	cl_assert_equal_i(0, expected.files_binary);
 
 	cl_assert_equal_i(1, expected.hunks);
 	cl_assert_equal_i(13, expected.lines);
@@ -103,8 +103,8 @@ void test_diff_blob__can_compare_text_blobs(void)
 		c, d, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(1, expected.files);
-	cl_assert_equal_i(1, expected.file_mods);
-	cl_assert(expected.at_least_one_of_them_is_binary == false);
+	cl_assert_equal_i(1, expected.file_status[GIT_DELTA_MODIFIED]);
+	cl_assert_equal_i(0, expected.files_binary);
 
 	cl_assert_equal_i(2, expected.hunks);
 	cl_assert_equal_i(14, expected.lines);
@@ -125,8 +125,8 @@ void test_diff_blob__can_compare_against_null_blobs(void)
 		d, e, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(1, expected.files);
-	cl_assert_equal_i(1, expected.file_dels);
-	cl_assert(expected.at_least_one_of_them_is_binary == false);
+	cl_assert_equal_i(1, expected.file_status[GIT_DELTA_DELETED]);
+	cl_assert_equal_i(0, expected.files_binary);
 
 	cl_assert_equal_i(1, expected.hunks);
 	cl_assert_equal_i(14, expected.hunk_old_lines);
@@ -140,8 +140,8 @@ void test_diff_blob__can_compare_against_null_blobs(void)
 		d, e, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(1, expected.files);
-	cl_assert_equal_i(1, expected.file_adds);
-	cl_assert(expected.at_least_one_of_them_is_binary == false);
+	cl_assert_equal_i(1, expected.file_status[GIT_DELTA_ADDED]);
+	cl_assert_equal_i(0, expected.files_binary);
 
 	cl_assert_equal_i(1, expected.hunks);
 	cl_assert_equal_i(14, expected.hunk_new_lines);
@@ -154,10 +154,9 @@ void test_diff_blob__can_compare_against_null_blobs(void)
 	cl_git_pass(git_diff_blobs(
 		alien, NULL, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.at_least_one_of_them_is_binary == true);
-
 	cl_assert_equal_i(1, expected.files);
-	cl_assert_equal_i(1, expected.file_dels);
+	cl_assert_equal_i(1, expected.files_binary);
+	cl_assert_equal_i(1, expected.file_status[GIT_DELTA_DELETED]);
 	cl_assert_equal_i(0, expected.hunks);
 	cl_assert_equal_i(0, expected.lines);
 
@@ -166,20 +165,19 @@ void test_diff_blob__can_compare_against_null_blobs(void)
 	cl_git_pass(git_diff_blobs(
 		NULL, alien, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.at_least_one_of_them_is_binary == true);
-
 	cl_assert_equal_i(1, expected.files);
-	cl_assert_equal_i(1, expected.file_adds);
+	cl_assert_equal_i(1, expected.files_binary);
+	cl_assert_equal_i(1, expected.file_status[GIT_DELTA_ADDED]);
 	cl_assert_equal_i(0, expected.hunks);
 	cl_assert_equal_i(0, expected.lines);
 }
 
-static void assert_identical_blobs_comparison(diff_expects expected)
+static void assert_identical_blobs_comparison(diff_expects *expected)
 {
-	cl_assert_equal_i(1, expected.files);
-	cl_assert_equal_i(1, expected.file_unmodified);
-	cl_assert_equal_i(0, expected.hunks);
-	cl_assert_equal_i(0, expected.lines);
+	cl_assert_equal_i(1, expected->files);
+	cl_assert_equal_i(1, expected->file_status[GIT_DELTA_UNMODIFIED]);
+	cl_assert_equal_i(0, expected->hunks);
+	cl_assert_equal_i(0, expected->lines);
 }
 
 void test_diff_blob__can_compare_identical_blobs(void)
@@ -187,32 +185,32 @@ void test_diff_blob__can_compare_identical_blobs(void)
 	cl_git_pass(git_diff_blobs(
 		d, d, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.at_least_one_of_them_is_binary == false);
-	assert_identical_blobs_comparison(expected);
+	cl_assert_equal_i(0, expected.files_binary);
+	assert_identical_blobs_comparison(&expected);
 
 	memset(&expected, 0, sizeof(expected));
 	cl_git_pass(git_diff_blobs(
 		NULL, NULL, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.at_least_one_of_them_is_binary == false);
-	assert_identical_blobs_comparison(expected);
+	cl_assert_equal_i(0, expected.files_binary);
+	assert_identical_blobs_comparison(&expected);
 
 	memset(&expected, 0, sizeof(expected));
 	cl_git_pass(git_diff_blobs(
 		alien, alien, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.at_least_one_of_them_is_binary == true);
-	assert_identical_blobs_comparison(expected);
+	cl_assert(expected.files_binary > 0);
+	assert_identical_blobs_comparison(&expected);
 }
 
-static void assert_binary_blobs_comparison(diff_expects expected)
+static void assert_binary_blobs_comparison(diff_expects *expected)
 {
-	cl_assert(expected.at_least_one_of_them_is_binary == true);
+	cl_assert(expected->files_binary > 0);
 
-	cl_assert_equal_i(1, expected.files);
-	cl_assert_equal_i(1, expected.file_mods);
-	cl_assert_equal_i(0, expected.hunks);
-	cl_assert_equal_i(0, expected.lines);
+	cl_assert_equal_i(1, expected->files);
+	cl_assert_equal_i(1, expected->file_status[GIT_DELTA_MODIFIED]);
+	cl_assert_equal_i(0, expected->hunks);
+	cl_assert_equal_i(0, expected->lines);
 }
 
 void test_diff_blob__can_compare_two_binary_blobs(void)
@@ -227,14 +225,14 @@ void test_diff_blob__can_compare_two_binary_blobs(void)
 	cl_git_pass(git_diff_blobs(
 		alien, heart, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	assert_binary_blobs_comparison(expected);
+	assert_binary_blobs_comparison(&expected);
 
 	memset(&expected, 0, sizeof(expected));
 
 	cl_git_pass(git_diff_blobs(
 		heart, alien, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	assert_binary_blobs_comparison(expected);
+	assert_binary_blobs_comparison(&expected);
 
 	git_blob_free(heart);
 }
@@ -244,14 +242,14 @@ void test_diff_blob__can_compare_a_binary_blob_and_a_text_blob(void)
 	cl_git_pass(git_diff_blobs(
 		alien, d, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	assert_binary_blobs_comparison(expected);
+	assert_binary_blobs_comparison(&expected);
 
 	memset(&expected, 0, sizeof(expected));
 
 	cl_git_pass(git_diff_blobs(
 		d, alien, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	assert_binary_blobs_comparison(expected);
+	assert_binary_blobs_comparison(&expected);
 }
 
 /*
diff --git a/tests-clar/diff/diff_helpers.c b/tests-clar/diff/diff_helpers.c
index de0e7e074..992c87d4c 100644
--- a/tests-clar/diff/diff_helpers.c
+++ b/tests-clar/diff/diff_helpers.c
@@ -32,20 +32,13 @@ int diff_file_fn(
 
 	e->files++;
 
-	if (delta->binary) {
-		e->at_least_one_of_them_is_binary = true;
+	if (delta->binary)
 		e->files_binary++;
-	}
 
-	switch (delta->status) {
-	case GIT_DELTA_ADDED: e->file_adds++; break;
-	case GIT_DELTA_DELETED: e->file_dels++; break;
-	case GIT_DELTA_MODIFIED: e->file_mods++; break;
-	case GIT_DELTA_IGNORED: e->file_ignored++; break;
-	case GIT_DELTA_UNTRACKED: e->file_untracked++; break;
-	case GIT_DELTA_UNMODIFIED: e->file_unmodified++; break;
-	default: break;
-	}
+	cl_assert(delta->status <= GIT_DELTA_TYPECHANGE);
+
+	e->file_status[delta->status] += 1;
+
 	return 0;
 }
 
diff --git a/tests-clar/diff/diff_helpers.h b/tests-clar/diff/diff_helpers.h
index 629130934..6ff493d49 100644
--- a/tests-clar/diff/diff_helpers.h
+++ b/tests-clar/diff/diff_helpers.h
@@ -8,12 +8,7 @@ typedef struct {
 	int files;
 	int files_binary;
 
-	int file_adds;
-	int file_dels;
-	int file_mods;
-	int file_ignored;
-	int file_untracked;
-	int file_unmodified;
+	int file_status[10]; /* indexed by git_delta_t value */
 
 	int hunks;
 	int hunk_new_lines;
@@ -23,8 +18,6 @@ typedef struct {
 	int line_ctxt;
 	int line_adds;
 	int line_dels;
-
-	bool at_least_one_of_them_is_binary;
 } diff_expects;
 
 extern int diff_file_fn(
diff --git a/tests-clar/diff/index.c b/tests-clar/diff/index.c
index 7c4bddb90..eda8f066a 100644
--- a/tests-clar/diff/index.c
+++ b/tests-clar/diff/index.c
@@ -45,9 +45,9 @@ void test_diff_index__0(void)
 	 * - mv .git .gitted
 	 */
 	cl_assert_equal_i(8, exp.files);
-	cl_assert_equal_i(3, exp.file_adds);
-	cl_assert_equal_i(2, exp.file_dels);
-	cl_assert_equal_i(3, exp.file_mods);
+	cl_assert_equal_i(3, exp.file_status[GIT_DELTA_ADDED]);
+	cl_assert_equal_i(2, exp.file_status[GIT_DELTA_DELETED]);
+	cl_assert_equal_i(3, exp.file_status[GIT_DELTA_MODIFIED]);
 
 	cl_assert_equal_i(8, exp.hunks);
 
@@ -73,9 +73,9 @@ void test_diff_index__0(void)
 	 * - mv .git .gitted
 	 */
 	cl_assert_equal_i(12, exp.files);
-	cl_assert_equal_i(7, exp.file_adds);
-	cl_assert_equal_i(2, exp.file_dels);
-	cl_assert_equal_i(3, exp.file_mods);
+	cl_assert_equal_i(7, exp.file_status[GIT_DELTA_ADDED]);
+	cl_assert_equal_i(2, exp.file_status[GIT_DELTA_DELETED]);
+	cl_assert_equal_i(3, exp.file_status[GIT_DELTA_MODIFIED]);
 
 	cl_assert_equal_i(12, exp.hunks);
 
diff --git a/tests-clar/diff/rename.c b/tests-clar/diff/rename.c
new file mode 100644
index 000000000..8a50fd5ea
--- /dev/null
+++ b/tests-clar/diff/rename.c
@@ -0,0 +1,105 @@
+#include "clar_libgit2.h"
+#include "diff_helpers.h"
+
+static git_repository *g_repo = NULL;
+
+void test_diff_rename__initialize(void)
+{
+	g_repo = cl_git_sandbox_init("renames");
+}
+
+void test_diff_rename__cleanup(void)
+{
+	cl_git_sandbox_cleanup();
+}
+
+/*
+ * Renames repo has:
+ *
+ * commit 31e47d8c1fa36d7f8d537b96158e3f024de0a9f2 -
+ *   serving.txt     (25 lines)
+ *   sevencities.txt (50 lines)
+ * commit 2bc7f351d20b53f1c72c16c4b036e491c478c49a -
+ *   serving.txt     -> sixserving.txt  (rename, no change, 100% match)
+ *   sevencities.txt -> sevencities.txt (no change)
+ *   sevencities.txt -> songofseven.txt (copy, no change, 100% match)
+ *
+ * TODO: add commits with various % changes of copy / rename
+ */
+
+void test_diff_rename__match_oid(void)
+{
+	const char *old_sha = "31e47d8c1fa36d7f8d537b96158e3f024de0a9f2";
+	const char *new_sha = "2bc7f351d20b53f1c72c16c4b036e491c478c49a";
+	git_tree *old_tree, *new_tree;
+	git_diff_list *diff;
+	git_diff_options diffopts = {0};
+	git_diff_detect_options opts;
+	diff_expects exp;
+
+	old_tree = resolve_commit_oid_to_tree(g_repo, old_sha);
+	new_tree = resolve_commit_oid_to_tree(g_repo, new_sha);
+
+	/* Must pass GIT_DIFF_INCLUDE_UNMODIFIED if you expect to emulate
+	 * --find-copies-harder during rename detection...
+	 */
+	memset(&diffopts, 0, sizeof(diffopts));
+	diffopts.flags |= GIT_DIFF_INCLUDE_UNMODIFIED;
+
+	cl_git_pass(git_diff_tree_to_tree(
+		g_repo, &diffopts, old_tree, new_tree, &diff));
+
+	/* git diff --no-renames \
+	 *          31e47d8c1fa36d7f8d537b96158e3f024de0a9f2 \
+	 *          2bc7f351d20b53f1c72c16c4b036e491c478c49a
+	 */
+	memset(&exp, 0, sizeof(exp));
+	cl_git_pass(git_diff_foreach(
+		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+
+	cl_assert_equal_i(4, exp.files);
+	cl_assert_equal_i(1, exp.file_status[GIT_DELTA_UNMODIFIED]);
+	cl_assert_equal_i(2, exp.file_status[GIT_DELTA_ADDED]);
+	cl_assert_equal_i(1, exp.file_status[GIT_DELTA_DELETED]);
+
+	/* git diff 31e47d8c1fa36d7f8d537b96158e3f024de0a9f2 \
+	 *          2bc7f351d20b53f1c72c16c4b036e491c478c49a
+	 */
+	cl_git_pass(git_diff_detect(diff, NULL));
+
+	memset(&exp, 0, sizeof(exp));
+	cl_git_pass(git_diff_foreach(
+		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+
+	cl_assert_equal_i(3, exp.files);
+	cl_assert_equal_i(1, exp.file_status[GIT_DELTA_UNMODIFIED]);
+	cl_assert_equal_i(1, exp.file_status[GIT_DELTA_ADDED]);
+	cl_assert_equal_i(1, exp.file_status[GIT_DELTA_RENAMED]);
+
+	git_diff_list_free(diff);
+
+	cl_git_pass(git_diff_tree_to_tree(
+		g_repo, &diffopts, old_tree, new_tree, &diff));
+
+	/* git diff --find-copies-harder \
+	 *          31e47d8c1fa36d7f8d537b96158e3f024de0a9f2 \
+	 *          2bc7f351d20b53f1c72c16c4b036e491c478c49a
+	 */
+	memset(&opts, 0, sizeof(opts));
+	opts.flags = GIT_DIFF_DETECT_COPIES_FROM_UNMODIFIED;
+	cl_git_pass(git_diff_detect(diff, &opts));
+
+	memset(&exp, 0, sizeof(exp));
+	cl_git_pass(git_diff_foreach(
+		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+
+	cl_assert_equal_i(3, exp.files);
+	cl_assert_equal_i(1, exp.file_status[GIT_DELTA_UNMODIFIED]);
+	cl_assert_equal_i(1, exp.file_status[GIT_DELTA_COPIED]);
+	cl_assert_equal_i(1, exp.file_status[GIT_DELTA_RENAMED]);
+
+	git_diff_list_free(diff);
+
+	git_tree_free(old_tree);
+	git_tree_free(new_tree);
+}
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);
 
diff --git a/tests-clar/diff/workdir.c b/tests-clar/diff/workdir.c
index 3e388ea70..e617560f7 100644
--- a/tests-clar/diff/workdir.c
+++ b/tests-clar/diff/workdir.c
@@ -46,11 +46,11 @@ void test_diff_workdir__to_index(void)
 		 * - mv .git .gitted
 		 */
 		cl_assert_equal_i(13, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(4, exp.file_dels);
-		cl_assert_equal_i(4, exp.file_mods);
-		cl_assert_equal_i(1, exp.file_ignored);
-		cl_assert_equal_i(4, exp.file_untracked);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_ADDED]);
+		cl_assert_equal_i(4, exp.file_status[GIT_DELTA_DELETED]);
+		cl_assert_equal_i(4, exp.file_status[GIT_DELTA_MODIFIED]);
+		cl_assert_equal_i(1, exp.file_status[GIT_DELTA_IGNORED]);
+		cl_assert_equal_i(4, exp.file_status[GIT_DELTA_UNTRACKED]);
 
 		cl_assert_equal_i(8, exp.hunks);
 
@@ -107,11 +107,11 @@ void test_diff_workdir__to_tree(void)
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 		cl_assert_equal_i(14, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(4, exp.file_dels);
-		cl_assert_equal_i(4, exp.file_mods);
-		cl_assert_equal_i(1, exp.file_ignored);
-		cl_assert_equal_i(5, exp.file_untracked);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_ADDED]);
+		cl_assert_equal_i(4, exp.file_status[GIT_DELTA_DELETED]);
+		cl_assert_equal_i(4, exp.file_status[GIT_DELTA_MODIFIED]);
+		cl_assert_equal_i(1, exp.file_status[GIT_DELTA_IGNORED]);
+		cl_assert_equal_i(5, exp.file_status[GIT_DELTA_UNTRACKED]);
 	}
 
 	/* Since there is no git diff equivalent, let's just assume that the
@@ -143,11 +143,11 @@ void test_diff_workdir__to_tree(void)
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 		cl_assert_equal_i(15, exp.files);
-		cl_assert_equal_i(2, exp.file_adds);
-		cl_assert_equal_i(5, exp.file_dels);
-		cl_assert_equal_i(4, exp.file_mods);
-		cl_assert_equal_i(1, exp.file_ignored);
-		cl_assert_equal_i(3, exp.file_untracked);
+		cl_assert_equal_i(2, exp.file_status[GIT_DELTA_ADDED]);
+		cl_assert_equal_i(5, exp.file_status[GIT_DELTA_DELETED]);
+		cl_assert_equal_i(4, exp.file_status[GIT_DELTA_MODIFIED]);
+		cl_assert_equal_i(1, exp.file_status[GIT_DELTA_IGNORED]);
+		cl_assert_equal_i(3, exp.file_status[GIT_DELTA_UNTRACKED]);
 
 		cl_assert_equal_i(11, exp.hunks);
 
@@ -180,11 +180,11 @@ void test_diff_workdir__to_tree(void)
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 		cl_assert_equal_i(16, exp.files);
-		cl_assert_equal_i(5, exp.file_adds);
-		cl_assert_equal_i(4, exp.file_dels);
-		cl_assert_equal_i(3, exp.file_mods);
-		cl_assert_equal_i(1, exp.file_ignored);
-		cl_assert_equal_i(3, exp.file_untracked);
+		cl_assert_equal_i(5, exp.file_status[GIT_DELTA_ADDED]);
+		cl_assert_equal_i(4, exp.file_status[GIT_DELTA_DELETED]);
+		cl_assert_equal_i(3, exp.file_status[GIT_DELTA_MODIFIED]);
+		cl_assert_equal_i(1, exp.file_status[GIT_DELTA_IGNORED]);
+		cl_assert_equal_i(3, exp.file_status[GIT_DELTA_UNTRACKED]);
 
 		cl_assert_equal_i(12, exp.hunks);
 
@@ -228,11 +228,11 @@ void test_diff_workdir__to_index_with_pathspec(void)
 			cl_git_pass(git_diff_foreach(diff, &exp, diff_file_fn, NULL, NULL));
 
 		cl_assert_equal_i(13, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(4, exp.file_dels);
-		cl_assert_equal_i(4, exp.file_mods);
-		cl_assert_equal_i(1, exp.file_ignored);
-		cl_assert_equal_i(4, exp.file_untracked);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_ADDED]);
+		cl_assert_equal_i(4, exp.file_status[GIT_DELTA_DELETED]);
+		cl_assert_equal_i(4, exp.file_status[GIT_DELTA_MODIFIED]);
+		cl_assert_equal_i(1, exp.file_status[GIT_DELTA_IGNORED]);
+		cl_assert_equal_i(4, exp.file_status[GIT_DELTA_UNTRACKED]);
 	}
 
 	git_diff_list_free(diff);
@@ -251,11 +251,11 @@ void test_diff_workdir__to_index_with_pathspec(void)
 			cl_git_pass(git_diff_foreach(diff, &exp, diff_file_fn, NULL, NULL));
 
 		cl_assert_equal_i(1, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(0, exp.file_dels);
-		cl_assert_equal_i(1, exp.file_mods);
-		cl_assert_equal_i(0, exp.file_ignored);
-		cl_assert_equal_i(0, exp.file_untracked);
+		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(1, exp.file_status[GIT_DELTA_MODIFIED]);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_IGNORED]);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_UNTRACKED]);
 	}
 
 	git_diff_list_free(diff);
@@ -274,11 +274,11 @@ void test_diff_workdir__to_index_with_pathspec(void)
 			cl_git_pass(git_diff_foreach(diff, &exp, diff_file_fn, NULL, NULL));
 
 		cl_assert_equal_i(3, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(1, exp.file_dels);
-		cl_assert_equal_i(1, exp.file_mods);
-		cl_assert_equal_i(0, exp.file_ignored);
-		cl_assert_equal_i(1, exp.file_untracked);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_ADDED]);
+		cl_assert_equal_i(1, exp.file_status[GIT_DELTA_DELETED]);
+		cl_assert_equal_i(1, exp.file_status[GIT_DELTA_MODIFIED]);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_IGNORED]);
+		cl_assert_equal_i(1, exp.file_status[GIT_DELTA_UNTRACKED]);
 	}
 
 	git_diff_list_free(diff);
@@ -297,11 +297,11 @@ void test_diff_workdir__to_index_with_pathspec(void)
 			cl_git_pass(git_diff_foreach(diff, &exp, diff_file_fn, NULL, NULL));
 
 		cl_assert_equal_i(2, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(2, exp.file_dels);
-		cl_assert_equal_i(0, exp.file_mods);
-		cl_assert_equal_i(0, exp.file_ignored);
-		cl_assert_equal_i(0, exp.file_untracked);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_ADDED]);
+		cl_assert_equal_i(2, exp.file_status[GIT_DELTA_DELETED]);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_MODIFIED]);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_IGNORED]);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_UNTRACKED]);
 	}
 
 	git_diff_list_free(diff);
@@ -337,7 +337,7 @@ void test_diff_workdir__filemode_changes(void)
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 		cl_assert_equal_i(0, exp.files);
-		cl_assert_equal_i(0, exp.file_mods);
+		cl_assert_equal_i(0, exp.file_status[GIT_DELTA_MODIFIED]);
 		cl_assert_equal_i(0, exp.hunks);
 	}
 
@@ -360,7 +360,7 @@ void test_diff_workdir__filemode_changes(void)
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 		cl_assert_equal_i(1, exp.files);
-		cl_assert_equal_i(1, exp.file_mods);
+		cl_assert_equal_i(1, exp.file_status[GIT_DELTA_MODIFIED]);
 		cl_assert_equal_i(0, exp.hunks);
 	}
 
@@ -393,7 +393,7 @@ void test_diff_workdir__filemode_changes_with_filemode_false(void)
 		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(0, exp.files);
-	cl_assert_equal_i(0, exp.file_mods);
+	cl_assert_equal_i(0, exp.file_status[GIT_DELTA_MODIFIED]);
 	cl_assert_equal_i(0, exp.hunks);
 
 	git_diff_list_free(diff);
@@ -409,7 +409,7 @@ void test_diff_workdir__filemode_changes_with_filemode_false(void)
 		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 	cl_assert_equal_i(0, exp.files);
-	cl_assert_equal_i(0, exp.file_mods);
+	cl_assert_equal_i(0, exp.file_status[GIT_DELTA_MODIFIED]);
 	cl_assert_equal_i(0, exp.hunks);
 
 	git_diff_list_free(diff);
@@ -456,9 +456,9 @@ void test_diff_workdir__head_index_and_workdir_all_differ(void)
 				diff_i2t, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 		cl_assert_equal_i(1, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(0, exp.file_dels);
-		cl_assert_equal_i(1, 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(1, exp.file_status[GIT_DELTA_MODIFIED]);
 		cl_assert_equal_i(1, exp.hunks);
 		cl_assert_equal_i(2, exp.lines);
 		cl_assert_equal_i(1, exp.line_ctxt);
@@ -477,9 +477,9 @@ void test_diff_workdir__head_index_and_workdir_all_differ(void)
 				diff_w2i, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 		cl_assert_equal_i(1, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(0, exp.file_dels);
-		cl_assert_equal_i(1, 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(1, exp.file_status[GIT_DELTA_MODIFIED]);
 		cl_assert_equal_i(1, exp.hunks);
 		cl_assert_equal_i(3, exp.lines);
 		cl_assert_equal_i(2, exp.line_ctxt);
@@ -500,9 +500,9 @@ void test_diff_workdir__head_index_and_workdir_all_differ(void)
 				diff_i2t, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 		cl_assert_equal_i(1, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(0, exp.file_dels);
-		cl_assert_equal_i(1, 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(1, exp.file_status[GIT_DELTA_MODIFIED]);
 		cl_assert_equal_i(1, exp.hunks);
 		cl_assert_equal_i(3, exp.lines);
 		cl_assert_equal_i(1, exp.line_ctxt);
@@ -542,9 +542,9 @@ void test_diff_workdir__eof_newline_changes(void)
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 		cl_assert_equal_i(0, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(0, exp.file_dels);
-		cl_assert_equal_i(0, 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(0, exp.file_status[GIT_DELTA_MODIFIED]);
 		cl_assert_equal_i(0, exp.hunks);
 		cl_assert_equal_i(0, exp.lines);
 		cl_assert_equal_i(0, exp.line_ctxt);
@@ -569,9 +569,9 @@ void test_diff_workdir__eof_newline_changes(void)
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 		cl_assert_equal_i(1, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(0, exp.file_dels);
-		cl_assert_equal_i(1, 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(1, exp.file_status[GIT_DELTA_MODIFIED]);
 		cl_assert_equal_i(1, exp.hunks);
 		cl_assert_equal_i(2, exp.lines);
 		cl_assert_equal_i(1, exp.line_ctxt);
@@ -596,9 +596,9 @@ void test_diff_workdir__eof_newline_changes(void)
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
 		cl_assert_equal_i(1, exp.files);
-		cl_assert_equal_i(0, exp.file_adds);
-		cl_assert_equal_i(0, exp.file_dels);
-		cl_assert_equal_i(1, 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(1, exp.file_status[GIT_DELTA_MODIFIED]);
 		cl_assert_equal_i(1, exp.hunks);
 		cl_assert_equal_i(3, exp.lines);
 		cl_assert_equal_i(0, exp.line_ctxt);
@@ -801,11 +801,11 @@ void test_diff_workdir__submodules(void)
 
 	cl_assert_equal_i(10, exp.files);
 
-	cl_assert_equal_i(0, exp.file_adds);
-	cl_assert_equal_i(0, exp.file_dels);
-	cl_assert_equal_i(1, exp.file_mods);
-	cl_assert_equal_i(0, exp.file_ignored);
-	cl_assert_equal_i(9, exp.file_untracked);
+	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(1, exp.file_status[GIT_DELTA_MODIFIED]);
+	cl_assert_equal_i(0, exp.file_status[GIT_DELTA_IGNORED]);
+	cl_assert_equal_i(9, exp.file_status[GIT_DELTA_UNTRACKED]);
 
 	/* the following numbers match "git diff 873585" exactly */
 
diff --git a/tests-clar/repo/head.c b/tests-clar/repo/head.c
index 22947168e..58f525e2b 100644
--- a/tests-clar/repo/head.c
+++ b/tests-clar/repo/head.c
@@ -180,8 +180,6 @@ void test_repo_head__retrieving_an_orphaned_head_returns_GIT_EORPHANEDHEAD(void)
 
 void test_repo_head__can_tell_if_an_orphaned_head_is_detached(void)
 {
-	git_reference *head;
-
 	make_head_orphaned(repo, NON_EXISTING_HEAD);
 
 	cl_assert_equal_i(false, git_repository_head_detached(repo));
diff --git a/tests-clar/resources/renames/.gitted/HEAD b/tests-clar/resources/renames/.gitted/HEAD
new file mode 100644
index 000000000..cb089cd89
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/HEAD
@@ -0,0 +1 @@
+ref: refs/heads/master
diff --git a/tests-clar/resources/renames/.gitted/config b/tests-clar/resources/renames/.gitted/config
new file mode 100644
index 000000000..bb4d11c1f
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/config
@@ -0,0 +1,7 @@
+[core]
+	repositoryformatversion = 0
+	filemode = true
+	bare = false
+	logallrefupdates = true
+	ignorecase = true
+	precomposeunicode = false
diff --git a/tests-clar/resources/renames/.gitted/description b/tests-clar/resources/renames/.gitted/description
new file mode 100644
index 000000000..498b267a8
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/description
@@ -0,0 +1 @@
+Unnamed repository; edit this file 'description' to name the repository.
diff --git a/tests-clar/resources/renames/.gitted/index b/tests-clar/resources/renames/.gitted/index
new file mode 100644
index 000000000..1fc69fcbe
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/index
diff --git a/tests-clar/resources/renames/.gitted/info/exclude b/tests-clar/resources/renames/.gitted/info/exclude
new file mode 100644
index 000000000..a5196d1be
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/info/exclude
@@ -0,0 +1,6 @@
+# git ls-files --others --exclude-from=.git/info/exclude
+# Lines that start with '#' are comments.
+# For a project mostly in C, the following would be a good set of
+# exclude patterns (uncomment them if you want to use them):
+# *.[oa]
+# *~
diff --git a/tests-clar/resources/renames/.gitted/logs/HEAD b/tests-clar/resources/renames/.gitted/logs/HEAD
new file mode 100644
index 000000000..34222ed7d
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/logs/HEAD
@@ -0,0 +1,2 @@
+0000000000000000000000000000000000000000 31e47d8c1fa36d7f8d537b96158e3f024de0a9f2 Russell Belfer <rb@github.com> 1351024687 -0700	commit (initial): Initial commit
+31e47d8c1fa36d7f8d537b96158e3f024de0a9f2 2bc7f351d20b53f1c72c16c4b036e491c478c49a Russell Belfer <rb@github.com> 1351024817 -0700	commit: copy and rename with no change
diff --git a/tests-clar/resources/renames/.gitted/logs/refs/heads/master b/tests-clar/resources/renames/.gitted/logs/refs/heads/master
new file mode 100644
index 000000000..34222ed7d
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/logs/refs/heads/master
@@ -0,0 +1,2 @@
+0000000000000000000000000000000000000000 31e47d8c1fa36d7f8d537b96158e3f024de0a9f2 Russell Belfer <rb@github.com> 1351024687 -0700	commit (initial): Initial commit
+31e47d8c1fa36d7f8d537b96158e3f024de0a9f2 2bc7f351d20b53f1c72c16c4b036e491c478c49a Russell Belfer <rb@github.com> 1351024817 -0700	commit: copy and rename with no change
diff --git a/tests-clar/resources/renames/.gitted/objects/03/da7ad872536bd448da8d88eb7165338bf923a7 b/tests-clar/resources/renames/.gitted/objects/03/da7ad872536bd448da8d88eb7165338bf923a7
new file mode 100644
index 000000000..2ee86444d
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/objects/03/da7ad872536bd448da8d88eb7165338bf923a7
diff --git a/tests-clar/resources/renames/.gitted/objects/2b/c7f351d20b53f1c72c16c4b036e491c478c49a b/tests-clar/resources/renames/.gitted/objects/2b/c7f351d20b53f1c72c16c4b036e491c478c49a
new file mode 100644
index 000000000..93f1ccb3f
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/objects/2b/c7f351d20b53f1c72c16c4b036e491c478c49a
diff --git a/tests-clar/resources/renames/.gitted/objects/31/e47d8c1fa36d7f8d537b96158e3f024de0a9f2 b/tests-clar/resources/renames/.gitted/objects/31/e47d8c1fa36d7f8d537b96158e3f024de0a9f2
new file mode 100644
index 000000000..00ce53212
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/objects/31/e47d8c1fa36d7f8d537b96158e3f024de0a9f2
diff --git a/tests-clar/resources/renames/.gitted/objects/61/8c6f2f8740bd6049b2fb9eb93fc15726462745 b/tests-clar/resources/renames/.gitted/objects/61/8c6f2f8740bd6049b2fb9eb93fc15726462745
new file mode 100644
index 000000000..24eac54c5
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/objects/61/8c6f2f8740bd6049b2fb9eb93fc15726462745
diff --git a/tests-clar/resources/renames/.gitted/objects/66/311f5cfbe7836c27510a3ba2f43e282e2c8bba b/tests-clar/resources/renames/.gitted/objects/66/311f5cfbe7836c27510a3ba2f43e282e2c8bba
new file mode 100644
index 000000000..5ee28a76a
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/objects/66/311f5cfbe7836c27510a3ba2f43e282e2c8bba
diff --git a/tests-clar/resources/renames/.gitted/objects/ad/0a8e55a104ac54a8a29ed4b84b49e76837a113 b/tests-clar/resources/renames/.gitted/objects/ad/0a8e55a104ac54a8a29ed4b84b49e76837a113
new file mode 100644
index 000000000..440b7bec3
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/objects/ad/0a8e55a104ac54a8a29ed4b84b49e76837a113
diff --git a/tests-clar/resources/renames/.gitted/refs/heads/master b/tests-clar/resources/renames/.gitted/refs/heads/master
new file mode 100644
index 000000000..049b1f5ad
--- /dev/null
+++ b/tests-clar/resources/renames/.gitted/refs/heads/master
@@ -0,0 +1 @@
+2bc7f351d20b53f1c72c16c4b036e491c478c49a
diff --git a/tests-clar/resources/renames/sevencities.txt b/tests-clar/resources/renames/sevencities.txt
new file mode 100644
index 000000000..66311f5cf
--- /dev/null
+++ b/tests-clar/resources/renames/sevencities.txt
@@ -0,0 +1,49 @@
+The Song of Seven Cities
+========================
+
+I WAS Lord of Cities very sumptuously builded.
+Seven roaring Cities paid me tribute from afar.
+Ivory their outposts were—the guardrooms of them gilded,
+And garrisoned with Amazons invincible in war.
+
+All the world went softly when it walked before my Cities—
+Neither King nor Army vexed my peoples at their toil,
+Never horse nor chariot irked or overbore my Cities,
+Never Mob nor Ruler questioned whence they drew their spoil.
+
+Banded, mailed and arrogant from sunrise unto sunset;
+Singing while they sacked it, they possessed the land at large.
+Yet when men would rob them, they resisted, they made onset
+And pierced the smoke of battle with a thousand-sabred charge.
+
+So they warred and trafficked only yesterday, my Cities.
+To-day there is no mark or mound of where my Cities stood.
+For the River rose at midnight and it washed away my Cities.
+They are evened with Atlantis and the towns before the Flood.
+
+Rain on rain-gorged channels raised the water-levels round them,
+Freshet backed on freshet swelled and swept their world from sight,
+Till the emboldened floods linked arms and, flashing forward, drowned them—
+Drowned my Seven Cities and their peoples in one night!
+
+Low among the alders lie their derelict foundations,
+The beams wherein they trusted and the plinths whereon they built—
+My rulers and their treasure and their unborn populations,
+Dead, destroyed, aborted, and defiled with mud and silt!
+
+The Daughters of the Palace whom they cherished in my Cities,
+My silver-tongued Princesses, and the promise of their May—
+Their bridegrooms of the June-tide—all have perished in my Cities,
+With the harsh envenomed virgins that can neither love nor play.
+
+I was Lord of Cities—I will build anew my Cities,
+Seven, set on rocks, above the wrath of any flood.
+Nor will I rest from search till I have filled anew my Cities
+With peoples undefeated of the dark, enduring blood.
+
+To the sound of trumpets shall their seed restore my Cities
+Wealthy and well-weaponed, that once more may I behold
+All the world go softly when it walks before my Cities,
+And the horses and the chariots fleeing from them as of old!
+
+                -- Rudyard Kipling
diff --git a/tests-clar/resources/renames/sixserving.txt b/tests-clar/resources/renames/sixserving.txt
new file mode 100644
index 000000000..ad0a8e55a
--- /dev/null
+++ b/tests-clar/resources/renames/sixserving.txt
@@ -0,0 +1,24 @@
+I KEEP six honest serving-men
+ (They taught me all I knew);
+Their names are What and Why and When
+ And How and Where and Who.
+I send them over land and sea,
+ I send them east and west;
+But after they have worked for me,
+ I give them all a rest.
+
+I let them rest from nine till five,
+ For I am busy then,
+As well as breakfast, lunch, and tea,
+ For they are hungry men.
+But different folk have different views;
+I know a person small—
+She keeps ten million serving-men,
+Who get no rest at all!
+
+She sends'em abroad on her own affairs,
+ From the second she opens her eyes—
+One million Hows, two million Wheres,
+And seven million Whys!
+
+                -- Rudyard Kipling
diff --git a/tests-clar/resources/renames/songofseven.txt b/tests-clar/resources/renames/songofseven.txt
new file mode 100644
index 000000000..66311f5cf
--- /dev/null
+++ b/tests-clar/resources/renames/songofseven.txt
@@ -0,0 +1,49 @@
+The Song of Seven Cities
+========================
+
+I WAS Lord of Cities very sumptuously builded.
+Seven roaring Cities paid me tribute from afar.
+Ivory their outposts were—the guardrooms of them gilded,
+And garrisoned with Amazons invincible in war.
+
+All the world went softly when it walked before my Cities—
+Neither King nor Army vexed my peoples at their toil,
+Never horse nor chariot irked or overbore my Cities,
+Never Mob nor Ruler questioned whence they drew their spoil.
+
+Banded, mailed and arrogant from sunrise unto sunset;
+Singing while they sacked it, they possessed the land at large.
+Yet when men would rob them, they resisted, they made onset
+And pierced the smoke of battle with a thousand-sabred charge.
+
+So they warred and trafficked only yesterday, my Cities.
+To-day there is no mark or mound of where my Cities stood.
+For the River rose at midnight and it washed away my Cities.
+They are evened with Atlantis and the towns before the Flood.
+
+Rain on rain-gorged channels raised the water-levels round them,
+Freshet backed on freshet swelled and swept their world from sight,
+Till the emboldened floods linked arms and, flashing forward, drowned them—
+Drowned my Seven Cities and their peoples in one night!
+
+Low among the alders lie their derelict foundations,
+The beams wherein they trusted and the plinths whereon they built—
+My rulers and their treasure and their unborn populations,
+Dead, destroyed, aborted, and defiled with mud and silt!
+
+The Daughters of the Palace whom they cherished in my Cities,
+My silver-tongued Princesses, and the promise of their May—
+Their bridegrooms of the June-tide—all have perished in my Cities,
+With the harsh envenomed virgins that can neither love nor play.
+
+I was Lord of Cities—I will build anew my Cities,
+Seven, set on rocks, above the wrath of any flood.
+Nor will I rest from search till I have filled anew my Cities
+With peoples undefeated of the dark, enduring blood.
+
+To the sound of trumpets shall their seed restore my Cities
+Wealthy and well-weaponed, that once more may I behold
+All the world go softly when it walks before my Cities,
+And the horses and the chariots fleeing from them as of old!
+
+                -- Rudyard Kipling