Diff iterators

This refactors the diff output code so that an iterator object
can be used to traverse and generate the diffs, instead of just
the `foreach()` style with callbacks.  The code has been rearranged
so that the two styles can still share most functions.

This also replaces `GIT_REVWALKOVER` with `GIT_ITEROVER` and uses
that as a common error code for marking the end of iteration when
using a iterator style of object.

include/git2/diff.h

@@ -169,7 +169,7 @@ enum {
 	GIT_DIFF_LINE_CONTEXT   = ' ',
 	GIT_DIFF_LINE_ADDITION  = '+',
 	GIT_DIFF_LINE_DELETION  = '-',
-	GIT_DIFF_LINE_ADD_EOFNL = '\n', /**< DEPRECATED */
+	GIT_DIFF_LINE_ADD_EOFNL = '\n', /**< DEPRECATED - will not be returned */
 	GIT_DIFF_LINE_DEL_EOFNL = '\0', /**< LF was removed at end of file */
 
 	/* The following values will only be sent to a `git_diff_data_fn` when
@@ -197,6 +197,11 @@ typedef int (*git_diff_data_fn)(
 	const char *content,
 	size_t content_len);
 
+/**
+ * The diff iterator object is used to scan a diff list.
+ */
+typedef struct git_diff_iterator git_diff_iterator;
+
 /** @name Diff List Generator Functions
  *
  * These are the functions you would use to create (or destroy) a
@@ -321,6 +326,60 @@ GIT_EXTERN(int) git_diff_merge(
  */
 /**@{*/
 
+/**
+ * Create a diff iterator object that can be used to traverse a diff.
+ */
+GIT_EXTERN(int) git_diff_iterator_new(
+	git_diff_iterator **iterator,
+	git_diff_list *diff);
+
+GIT_EXTERN(void) git_diff_iterator_free(git_diff_iterator *iter);
+
+/**
+ * Return the number of files in the diff.
+ */
+GIT_EXTERN(int) git_diff_iterator_num_files(git_diff_iterator *iterator);
+
+GIT_EXTERN(int) git_diff_iterator_num_hunks_in_file(git_diff_iterator *iterator);
+
+GIT_EXTERN(int) git_diff_iterator_num_lines_in_hunk(git_diff_iterator *iterator);
+
+/**
+ * Return the delta information for the next file in the diff.
+ *
+ * This will return a pointer to the next git_diff_delta` to be processed or
+ * NULL if the iterator is at the end of the diff, then advance.
+ */
+GIT_EXTERN(int) git_diff_iterator_next_file(
+	git_diff_delta **delta,
+	git_diff_iterator *iterator);
+
+/**
+ * Return the hunk information for the next hunk in the current file.
+ *
+ * It is recommended that you not call this if the file is a binary
+ * file, but it is allowed to do so.
+ *
+ * Warning! Call this function for the first time on a file is when the
+ * actual text diff will be computed (it cannot be computed incrementally)
+ * so the first call for a new file is expensive (at least in relative
+ * terms - in reality, it is still pretty darn fast).
+ */
+GIT_EXTERN(int) git_diff_iterator_next_hunk(
+	git_diff_range **range,
+	const char **header,
+	size_t *header_len,
+	git_diff_iterator *iterator);
+
+/**
+ * Return the next line of the current hunk of diffs.
+ */
+GIT_EXTERN(int) git_diff_iterator_next_line(
+	char *line_origin, /**< GIT_DIFF_LINE_... value from above */
+	const char **content,
+	size_t *content_len,
+	git_diff_iterator *iterator);
+
 /**
  * Iterate over a diff list issuing callbacks.
  *

include/git2/errors.h

@@ -28,7 +28,7 @@ enum {
 	GIT_EUSER = -7,
 
 	GIT_PASSTHROUGH = -30,
-	GIT_REVWALKOVER = -31,
+	GIT_ITEROVER = -31,
 };
 
 typedef struct {

include/git2/revwalk.h

@@ -201,7 +201,7 @@ GIT_EXTERN(int) git_revwalk_hide_ref(git_revwalk *walk, const char *refname);
  * @param oid Pointer where to store the oid of the next commit
  * @param walk the walker to pop the commit from.
  * @return 0 if the next commit was found;
- *	GIT_REVWALKOVER if there are no commits left to iterate
+ *	GIT_ITEROVER if there are no commits left to iterate
  */
 GIT_EXTERN(int) git_revwalk_next(git_oid *oid, git_revwalk *walk);
 

src/attr.c

@@ -188,6 +188,7 @@ int git_attr_foreach(
 
 				error = callback(assign->name, assign->value, payload);
 				if (error) {
+					giterr_clear();
 					error = GIT_EUSER;
 					goto cleanup;
 				}

src/config_file.c

@@ -221,6 +221,7 @@ static int file_foreach(
 
 			/* abort iterator on non-zero return value */
 			if (fn(key, var->value, data)) {
+				giterr_clear();
 				result = GIT_EUSER;
 				goto cleanup;
 			}

src/diff.c

@@ -316,6 +316,7 @@ static git_diff_list *git_diff_list_alloc(
 	if (diff == NULL)
 		return NULL;
 
+	GIT_REFCOUNT_INC(diff);
 	diff->repo = repo;
 
 	if (git_vector_init(&diff->deltas, 0, diff_delta__cmp) < 0 ||
@@ -391,15 +392,12 @@ fail:
 	return NULL;
 }
 
-void git_diff_list_free(git_diff_list *diff)
+static void diff_list_free(git_diff_list *diff)
 {
 	git_diff_delta *delta;
 	git_attr_fnmatch *match;
 	unsigned int i;
 
-	if (!diff)
-		return;
-
 	git_vector_foreach(&diff->deltas, i, delta) {
 		git__free(delta);
 		diff->deltas.contents[i] = NULL;
@@ -416,6 +414,14 @@ void git_diff_list_free(git_diff_list *diff)
 	git__free(diff);
 }
 
+void git_diff_list_free(git_diff_list *diff)
+{
+	if (!diff)
+		return;
+
+	GIT_REFCOUNT_DEC(diff, diff_list_free);
+}
+
 static int oid_for_workdir_item(
 	git_repository *repo,
 	const git_index_entry *item,

src/diff.h

@@ -26,6 +26,7 @@ enum {
 };
 
 struct git_diff_list {
+	git_refcount     rc;
 	git_repository   *repo;
 	git_diff_options opts;
 	git_vector       pathspec;

src/fetch.c

@@ -221,7 +221,7 @@ int git_fetch_negotiate(git_remote *remote)
 		}
 	}
 
-	if (error < 0 && error != GIT_REVWALKOVER)
+	if (error < 0 && error != GIT_ITEROVER)
 		goto on_error;
 
 	/* Tell the other end that we're done negotiating */

src/pool.h

@@ -75,6 +75,17 @@ extern void git_pool_swap(git_pool *a, git_pool *b);
  */
 extern void *git_pool_malloc(git_pool *pool, uint32_t items);
 
+/**
+ * Allocate space and zero it out.
+ */
+GIT_INLINE(void *) git_pool_mallocz(git_pool *pool, uint32_t items)
+{
+	void *ptr = git_pool_malloc(pool, items);
+	if (ptr)
+		memset(ptr, 0, (size_t)items * (size_t)pool->item_size);
+	return ptr;
+}
+
 /**
  * Allocate space and duplicate string data into it.
  *

src/refs.c

@@ -1643,7 +1643,6 @@ int git_reference_normalize_name(
 			}
 		}
 
-
 		*buffer_out++ = *current++;
 		buffer_size--;
 	}

src/revparse.c

@@ -493,7 +493,7 @@ static int walk_and_search(git_object **out, git_revwalk *walk, regex_t *regex)
 		git_object_free(obj);
 	}
 
-	if (error < 0 && error == GIT_REVWALKOVER)
+	if (error < 0 && error == GIT_ITEROVER)
 		error = GIT_ENOTFOUND;
 
 	return error;

src/revwalk.c

@@ -449,6 +449,7 @@ int git_merge_base(git_oid *out, git_repository *repo, git_oid *one, git_oid *tw
 
 	if (!result) {
 		git_revwalk_free(walk);
+		giterr_clear();
 		return GIT_ENOTFOUND;
 	}
 
@@ -682,7 +683,8 @@ static int revwalk_next_timesort(commit_object **object_out, git_revwalk *walk)
 		}
 	}
 
-	return GIT_REVWALKOVER;
+	giterr_clear();
+	return GIT_ITEROVER;
 }
 
 static int revwalk_next_unsorted(commit_object **object_out, git_revwalk *walk)
@@ -700,7 +702,8 @@ static int revwalk_next_unsorted(commit_object **object_out, git_revwalk *walk)
 		}
 	}
 
-	return GIT_REVWALKOVER;
+	giterr_clear();
+	return GIT_ITEROVER;
 }
 
 static int revwalk_next_toposort(commit_object **object_out, git_revwalk *walk)
@@ -710,8 +713,10 @@ static int revwalk_next_toposort(commit_object **object_out, git_revwalk *walk)
 
 	for (;;) {
 		next = commit_list_pop(&walk->iterator_topo);
-		if (next == NULL)
+		if (next == NULL) {
-			return GIT_REVWALKOVER;
+			giterr_clear();
+			return GIT_ITEROVER;
+		}
 
 		if (next->in_degree > 0) {
 			next->topo_delay = 1;
@@ -736,7 +741,7 @@ static int revwalk_next_toposort(commit_object **object_out, git_revwalk *walk)
 static int revwalk_next_reverse(commit_object **object_out, git_revwalk *walk)
 {
 	*object_out = commit_list_pop(&walk->iterator_reverse);
-	return *object_out ? 0 : GIT_REVWALKOVER;
+	return *object_out ? 0 : GIT_ITEROVER;
 }
 
 
@@ -751,8 +756,10 @@ static int prepare_walk(git_revwalk *walk)
 	 * If walk->one is NULL, there were no positive references,
 	 * so we know that the walk is already over.
 	 */
-	if (walk->one == NULL)
+	if (walk->one == NULL) {
-		return GIT_REVWALKOVER;
+		giterr_clear();
+		return GIT_ITEROVER;
+	}
 
 	/* first figure out what the merge bases are */
 	if (merge_bases_many(&bases, walk, walk->one, &walk->twos) < 0)
@@ -780,7 +787,7 @@ static int prepare_walk(git_revwalk *walk)
 				return -1;
 		}
 
-		if (error != GIT_REVWALKOVER)
+		if (error != GIT_ITEROVER)
 			return error;
 
 		walk->get_next = &revwalk_next_toposort;
@@ -792,7 +799,7 @@ static int prepare_walk(git_revwalk *walk)
 			if (commit_list_insert(next, &walk->iterator_reverse) == NULL)
 				return -1;
 
-		if (error != GIT_REVWALKOVER)
+		if (error != GIT_ITEROVER)
 			return error;
 
 		walk->get_next = &revwalk_next_reverse;
@@ -891,9 +898,10 @@ int git_revwalk_next(git_oid *oid, git_revwalk *walk)
 
 	error = walk->get_next(&next, walk);
 
-	if (error == GIT_REVWALKOVER) {
+	if (error == GIT_ITEROVER) {
 		git_revwalk_reset(walk);
-		return GIT_REVWALKOVER;
+		giterr_clear();
+		return GIT_ITEROVER;
 	}
 
 	if (!error)

src/status.c

@@ -151,6 +151,9 @@ cleanup:
 	git_diff_list_free(idx2head);
 	git_diff_list_free(wd2idx);
 
+	if (err == GIT_EUSER)
+		giterr_clear();
+
 	return err;
 }
 

src/submodule.c

@@ -163,6 +163,7 @@ int git_submodule_foreach(
 		}
 
 		if (callback(sm, sm->name, payload)) {
+			giterr_clear();
 			error = GIT_EUSER;
 			break;
 		}

tests-clar/diff/blob.c

@@ -58,59 +58,59 @@ void test_diff_blob__can_compare_text_blobs(void)
 	cl_git_pass(git_diff_blobs(
 		a, b, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.files == 1);
+	cl_assert_equal_i(1, expected.files);
-	cl_assert(expected.file_mods == 1);
+	cl_assert_equal_i(1, expected.file_mods);
 	cl_assert(expected.at_least_one_of_them_is_binary == false);
 
-	cl_assert(expected.hunks == 1);
+	cl_assert_equal_i(1, expected.hunks);
-	cl_assert(expected.lines == 6);
+	cl_assert_equal_i(6, expected.lines);
-	cl_assert(expected.line_ctxt == 1);
+	cl_assert_equal_i(1, expected.line_ctxt);
-	cl_assert(expected.line_adds == 5);
+	cl_assert_equal_i(5, expected.line_adds);
-	cl_assert(expected.line_dels == 0);
+	cl_assert_equal_i(0, expected.line_dels);
 
 	/* diff on tests/resources/attr/root_test2 */
 	memset(&expected, 0, sizeof(expected));
 	cl_git_pass(git_diff_blobs(
 		b, c, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.files == 1);
+	cl_assert_equal_i(1, expected.files);
-	cl_assert(expected.file_mods == 1);
+	cl_assert_equal_i(1, expected.file_mods);
 	cl_assert(expected.at_least_one_of_them_is_binary == false);
 
-	cl_assert(expected.hunks == 1);
+	cl_assert_equal_i(1, expected.hunks);
-	cl_assert(expected.lines == 15);
+	cl_assert_equal_i(15, expected.lines);
-	cl_assert(expected.line_ctxt == 3);
+	cl_assert_equal_i(3, expected.line_ctxt);
-	cl_assert(expected.line_adds == 9);
+	cl_assert_equal_i(9, expected.line_adds);
-	cl_assert(expected.line_dels == 3);
+	cl_assert_equal_i(3, expected.line_dels);
 
 	/* diff on tests/resources/attr/root_test3 */
 	memset(&expected, 0, sizeof(expected));
 	cl_git_pass(git_diff_blobs(
 		a, c, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.files == 1);
+	cl_assert_equal_i(1, expected.files);
-	cl_assert(expected.file_mods == 1);
+	cl_assert_equal_i(1, expected.file_mods);
 	cl_assert(expected.at_least_one_of_them_is_binary == false);
 
-	cl_assert(expected.hunks == 1);
+	cl_assert_equal_i(1, expected.hunks);
-	cl_assert(expected.lines == 13);
+	cl_assert_equal_i(13, expected.lines);
-	cl_assert(expected.line_ctxt == 0);
+	cl_assert_equal_i(0, expected.line_ctxt);
-	cl_assert(expected.line_adds == 12);
+	cl_assert_equal_i(12, expected.line_adds);
-	cl_assert(expected.line_dels == 1);
+	cl_assert_equal_i(1, expected.line_dels);
 
 	memset(&expected, 0, sizeof(expected));
 	cl_git_pass(git_diff_blobs(
 		c, d, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.files == 1);
+	cl_assert_equal_i(1, expected.files);
-	cl_assert(expected.file_mods == 1);
+	cl_assert_equal_i(1, expected.file_mods);
 	cl_assert(expected.at_least_one_of_them_is_binary == false);
 
-	cl_assert(expected.hunks == 2);
+	cl_assert_equal_i(2, expected.hunks);
-	cl_assert(expected.lines == 14);
+	cl_assert_equal_i(14, expected.lines);
-	cl_assert(expected.line_ctxt == 4);
+	cl_assert_equal_i(4, expected.line_ctxt);
-	cl_assert(expected.line_adds == 6);
+	cl_assert_equal_i(6, expected.line_adds);
-	cl_assert(expected.line_dels == 4);
+	cl_assert_equal_i(4, expected.line_dels);
 
 	git_blob_free(a);
 	git_blob_free(b);
@@ -124,14 +124,14 @@ void test_diff_blob__can_compare_against_null_blobs(void)
 	cl_git_pass(git_diff_blobs(
 		d, e, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.files == 1);
+	cl_assert_equal_i(1, expected.files);
-	cl_assert(expected.file_dels == 1);
+	cl_assert_equal_i(1, expected.file_dels);
 	cl_assert(expected.at_least_one_of_them_is_binary == false);
 
-	cl_assert(expected.hunks == 1);
+	cl_assert_equal_i(1, expected.hunks);
-	cl_assert(expected.hunk_old_lines == 14);
+	cl_assert_equal_i(14, expected.hunk_old_lines);
-	cl_assert(expected.lines == 14);
+	cl_assert_equal_i(14, expected.lines);
-	cl_assert(expected.line_dels == 14);
+	cl_assert_equal_i(14, expected.line_dels);
 
 	opts.flags |= GIT_DIFF_REVERSE;
 	memset(&expected, 0, sizeof(expected));
@@ -139,14 +139,14 @@ void test_diff_blob__can_compare_against_null_blobs(void)
 	cl_git_pass(git_diff_blobs(
 		d, e, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.files == 1);
+	cl_assert_equal_i(1, expected.files);
-	cl_assert(expected.file_adds == 1);
+	cl_assert_equal_i(1, expected.file_adds);
 	cl_assert(expected.at_least_one_of_them_is_binary == false);
 
-	cl_assert(expected.hunks == 1);
+	cl_assert_equal_i(1, expected.hunks);
-	cl_assert(expected.hunk_new_lines == 14);
+	cl_assert_equal_i(14, expected.hunk_new_lines);
-	cl_assert(expected.lines == 14);
+	cl_assert_equal_i(14, expected.lines);
-	cl_assert(expected.line_adds == 14);
+	cl_assert_equal_i(14, expected.line_adds);
 
 	opts.flags ^= GIT_DIFF_REVERSE;
 	memset(&expected, 0, sizeof(expected));
@@ -156,10 +156,10 @@ void test_diff_blob__can_compare_against_null_blobs(void)
 
 	cl_assert(expected.at_least_one_of_them_is_binary == true);
 
-	cl_assert(expected.files == 1);
+	cl_assert_equal_i(1, expected.files);
-	cl_assert(expected.file_dels == 1);
+	cl_assert_equal_i(1, expected.file_dels);
-	cl_assert(expected.hunks == 0);
+	cl_assert_equal_i(0, expected.hunks);
-	cl_assert(expected.lines == 0);
+	cl_assert_equal_i(0, expected.lines);
 
 	memset(&expected, 0, sizeof(expected));
 
@@ -168,18 +168,18 @@ void test_diff_blob__can_compare_against_null_blobs(void)
 
 	cl_assert(expected.at_least_one_of_them_is_binary == true);
 
-	cl_assert(expected.files == 1);
+	cl_assert_equal_i(1, expected.files);
-	cl_assert(expected.file_adds == 1);
+	cl_assert_equal_i(1, expected.file_adds);
-	cl_assert(expected.hunks == 0);
+	cl_assert_equal_i(0, expected.hunks);
-	cl_assert(expected.lines == 0);
+	cl_assert_equal_i(0, expected.lines);
 }
 
 static void assert_identical_blobs_comparison(diff_expects expected)
 {
-	cl_assert(expected.files == 1);
+	cl_assert_equal_i(1, expected.files);
-	cl_assert(expected.file_unmodified == 1);
+	cl_assert_equal_i(1, expected.file_unmodified);
-	cl_assert(expected.hunks == 0);
+	cl_assert_equal_i(0, expected.hunks);
-	cl_assert(expected.lines == 0);
+	cl_assert_equal_i(0, expected.lines);
 }
 
 void test_diff_blob__can_compare_identical_blobs(void)
@@ -209,10 +209,10 @@ static void assert_binary_blobs_comparison(diff_expects expected)
 {
 	cl_assert(expected.at_least_one_of_them_is_binary == true);
 
-	cl_assert(expected.files == 1);
+	cl_assert_equal_i(1, expected.files);
-	cl_assert(expected.file_mods == 1);
+	cl_assert_equal_i(1, expected.file_mods);
-	cl_assert(expected.hunks == 0);
+	cl_assert_equal_i(0, expected.hunks);
-	cl_assert(expected.lines == 0);
+	cl_assert_equal_i(0, expected.lines);
 }
 
 void test_diff_blob__can_compare_two_binary_blobs(void)
@@ -292,7 +292,7 @@ void test_diff_blob__comparing_two_text_blobs_honors_interhunkcontext(void)
 	cl_git_pass(git_diff_blobs(
 		old_d, d, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.hunks == 2);
+	cl_assert_equal_i(2, expected.hunks);
 
 	/* Test with inter-hunk-context explicitly set to 0 */
 	opts.interhunk_lines = 0;
@@ -300,7 +300,7 @@ void test_diff_blob__comparing_two_text_blobs_honors_interhunkcontext(void)
 	cl_git_pass(git_diff_blobs(
 		old_d, d, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.hunks == 2);
+	cl_assert_equal_i(2, expected.hunks);
 
 	/* Test with inter-hunk-context explicitly set to 1 */
 	opts.interhunk_lines = 1;
@@ -308,7 +308,7 @@ void test_diff_blob__comparing_two_text_blobs_honors_interhunkcontext(void)
 	cl_git_pass(git_diff_blobs(
 		old_d, d, &opts, &expected, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(expected.hunks == 1);
+	cl_assert_equal_i(1, expected.hunks);
 
 	git_blob_free(old_d);
 }

tests-clar/diff/diff_helpers.c

@@ -103,3 +103,74 @@ int diff_line_fn(
 	}
 	return 0;
 }
+
+int diff_foreach_via_iterator(
+	git_diff_list *diff,
+	void *data,
+	git_diff_file_fn file_cb,
+	git_diff_hunk_fn hunk_cb,
+	git_diff_data_fn line_cb)
+{
+	int error, curr, total;
+	git_diff_iterator *iter;
+	git_diff_delta *delta;
+
+	if ((error = git_diff_iterator_new(&iter, diff)) < 0)
+		return error;
+
+	curr  = 0;
+	total = git_diff_iterator_num_files(iter);
+
+	while (!(error = git_diff_iterator_next_file(&delta, iter))) {
+		git_diff_range *range;
+		const char *hdr;
+		size_t hdr_len;
+
+		/* call file_cb for this file */
+		if (file_cb != NULL && file_cb(data, delta, (float)curr / total) != 0)
+			goto abort;
+
+		if (!hunk_cb && !line_cb)
+			continue;
+
+		while (!(error = git_diff_iterator_next_hunk(
+				&range, &hdr, &hdr_len, iter))) {
+			char origin;
+			const char *line;
+			size_t line_len;
+
+			if (hunk_cb && hunk_cb(data, delta, range, hdr, hdr_len) != 0)
+				goto abort;
+
+			if (!line_cb)
+				continue;
+
+			while (!(error = git_diff_iterator_next_line(
+				&origin, &line, &line_len, iter))) {
+
+				if (line_cb(data, delta, range, origin, line, line_len) != 0)
+					goto abort;
+			}
+
+			if (error && error != GIT_ITEROVER)
+				goto done;
+		}
+
+		if (error && error != GIT_ITEROVER)
+			goto done;
+	}
+
+done:
+	git_diff_iterator_free(iter);
+
+	if (error == GIT_ITEROVER)
+		error = 0;
+
+	return error;
+
+abort:
+	git_diff_iterator_free(iter);
+	giterr_clear();
+
+	return GIT_EUSER;
+}

tests-clar/diff/diff_helpers.h

@@ -45,3 +45,9 @@ extern int diff_line_fn(
 	const char *content,
 	size_t content_len);
 
+extern int diff_foreach_via_iterator(
+	git_diff_list *diff,
+	void *data,
+	git_diff_file_fn file_cb,
+	git_diff_hunk_fn hunk_cb,
+	git_diff_data_fn line_cb);

tests-clar/diff/diffiter.c

@@ -0,0 +1,116 @@
+#include "clar_libgit2.h"
+#include "diff_helpers.h"
+
+void test_diff_diffiter__initialize(void)
+{
+}
+
+void test_diff_diffiter__cleanup(void)
+{
+	cl_git_sandbox_cleanup();
+}
+
+void test_diff_diffiter__create(void)
+{
+	git_repository *repo = cl_git_sandbox_init("attr");
+	git_diff_list *diff;
+	git_diff_iterator *iter;
+
+	cl_git_pass(git_diff_workdir_to_index(repo, NULL, &diff));
+	cl_git_pass(git_diff_iterator_new(&iter, diff));
+	git_diff_iterator_free(iter);
+	git_diff_list_free(diff);
+}
+
+void test_diff_diffiter__iterate_files(void)
+{
+	git_repository *repo = cl_git_sandbox_init("attr");
+	git_diff_list *diff;
+	git_diff_iterator *iter;
+	git_diff_delta *delta;
+	int error, count = 0;
+
+	cl_git_pass(git_diff_workdir_to_index(repo, NULL, &diff));
+	cl_git_pass(git_diff_iterator_new(&iter, diff));
+
+	while ((error = git_diff_iterator_next_file(&delta, iter)) != GIT_ITEROVER) {
+		cl_assert_equal_i(0, error);
+		cl_assert(delta != NULL);
+		count++;
+	}
+
+	cl_assert_equal_i(GIT_ITEROVER, error);
+	cl_assert(delta == NULL);
+	cl_assert_equal_i(6, count);
+
+	git_diff_iterator_free(iter);
+	git_diff_list_free(diff);
+}
+
+void test_diff_diffiter__iterate_files_2(void)
+{
+	git_repository *repo = cl_git_sandbox_init("status");
+	git_diff_list *diff;
+	git_diff_iterator *iter;
+	git_diff_delta *delta;
+	int error, count = 0;
+
+	cl_git_pass(git_diff_workdir_to_index(repo, NULL, &diff));
+	cl_git_pass(git_diff_iterator_new(&iter, diff));
+
+	while ((error = git_diff_iterator_next_file(&delta, iter)) != GIT_ITEROVER) {
+		cl_assert_equal_i(0, error);
+		cl_assert(delta != NULL);
+		count++;
+	}
+
+	cl_assert_equal_i(GIT_ITEROVER, error);
+	cl_assert(delta == NULL);
+	cl_assert_equal_i(8, count);
+
+	git_diff_iterator_free(iter);
+	git_diff_list_free(diff);
+}
+
+void test_diff_diffiter__iterate_files_and_hunks(void)
+{
+	git_repository *repo = cl_git_sandbox_init("status");
+	git_diff_options opts = {0};
+	git_diff_list *diff = NULL;
+	git_diff_iterator *iter;
+	git_diff_delta *delta;
+	git_diff_range *range;
+	const char *header;
+	size_t header_len;
+	int error, file_count = 0, hunk_count = 0;
+
+	opts.context_lines = 3;
+	opts.interhunk_lines = 1;
+	opts.flags |= GIT_DIFF_INCLUDE_IGNORED | GIT_DIFF_INCLUDE_UNTRACKED;
+
+	cl_git_pass(git_diff_workdir_to_index(repo, &opts, &diff));
+
+	cl_git_pass(git_diff_iterator_new(&iter, diff));
+
+	while ((error = git_diff_iterator_next_file(&delta, iter)) != GIT_ITEROVER) {
+		cl_assert_equal_i(0, error);
+		cl_assert(delta);
+
+		file_count++;
+
+		while ((error = git_diff_iterator_next_hunk(
+				&range, &header, &header_len, iter)) != GIT_ITEROVER) {
+			cl_assert_equal_i(0, error);
+			cl_assert(range);
+			hunk_count++;
+		}
+	}
+
+	cl_assert_equal_i(GIT_ITEROVER, error);
+	cl_assert(delta == NULL);
+	cl_assert_equal_i(13, file_count);
+	cl_assert_equal_i(8, hunk_count);
+
+	git_diff_iterator_free(iter);
+	git_diff_list_free(diff);
+}

tests-clar/diff/index.c

@@ -44,17 +44,17 @@ void test_diff_index__0(void)
 	 * - git diff -U1 --cached 26a125ee1bf
 	 * - mv .git .gitted
 	 */
-	cl_assert(exp.files == 8);
+	cl_assert_equal_i(8, exp.files);
-	cl_assert(exp.file_adds == 3);
+	cl_assert_equal_i(3, exp.file_adds);
-	cl_assert(exp.file_dels == 2);
+	cl_assert_equal_i(2, exp.file_dels);
-	cl_assert(exp.file_mods == 3);
+	cl_assert_equal_i(3, exp.file_mods);
 
-	cl_assert(exp.hunks == 8);
+	cl_assert_equal_i(8, exp.hunks);
 
-	cl_assert(exp.lines == 11);
+	cl_assert_equal_i(11, exp.lines);
-	cl_assert(exp.line_ctxt == 3);
+	cl_assert_equal_i(3, exp.line_ctxt);
-	cl_assert(exp.line_adds == 6);
+	cl_assert_equal_i(6, exp.line_adds);
-	cl_assert(exp.line_dels == 2);
+	cl_assert_equal_i(2, exp.line_dels);
 
 	git_diff_list_free(diff);
 	diff = NULL;
@@ -72,17 +72,17 @@ void test_diff_index__0(void)
 	 * - git diff -U1 --cached 0017bd4ab1ec3
 	 * - mv .git .gitted
 	 */
-	cl_assert(exp.files == 12);
+	cl_assert_equal_i(12, exp.files);
-	cl_assert(exp.file_adds == 7);
+	cl_assert_equal_i(7, exp.file_adds);
-	cl_assert(exp.file_dels == 2);
+	cl_assert_equal_i(2, exp.file_dels);
-	cl_assert(exp.file_mods == 3);
+	cl_assert_equal_i(3, exp.file_mods);
 
-	cl_assert(exp.hunks == 12);
+	cl_assert_equal_i(12, exp.hunks);
 
-	cl_assert(exp.lines == 16);
+	cl_assert_equal_i(16, exp.lines);
-	cl_assert(exp.line_ctxt == 3);
+	cl_assert_equal_i(3, exp.line_ctxt);
-	cl_assert(exp.line_adds == 11);
+	cl_assert_equal_i(11, exp.line_adds);
-	cl_assert(exp.line_dels == 2);
+	cl_assert_equal_i(2, exp.line_dels);
 
 	git_diff_list_free(diff);
 	diff = NULL;
@@ -132,7 +132,7 @@ void test_diff_index__1(void)
 		git_diff_foreach(diff, &exp, diff_stop_after_2_files, NULL, NULL)
 	);
 
-	cl_assert(exp.files == 2);
+	cl_assert_equal_i(2, exp.files);
 
 	git_diff_list_free(diff);
 	diff = NULL;

tests-clar/diff/tree.c

@@ -39,17 +39,17 @@ void test_diff_tree__0(void)
 	cl_git_pass(git_diff_foreach(
 		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(exp.files == 5);
+	cl_assert_equal_i(5, exp.files);
-	cl_assert(exp.file_adds == 2);
+	cl_assert_equal_i(2, exp.file_adds);
-	cl_assert(exp.file_dels == 1);
+	cl_assert_equal_i(1, exp.file_dels);
-	cl_assert(exp.file_mods == 2);
+	cl_assert_equal_i(2, exp.file_mods);
 
-	cl_assert(exp.hunks == 5);
+	cl_assert_equal_i(5, exp.hunks);
 
-	cl_assert(exp.lines == 7 + 24 + 1 + 6 + 6);
+	cl_assert_equal_i(7 + 24 + 1 + 6 + 6, exp.lines);
-	cl_assert(exp.line_ctxt == 1);
+	cl_assert_equal_i(1, exp.line_ctxt);
-	cl_assert(exp.line_adds == 24 + 1 + 5 + 5);
+	cl_assert_equal_i(24 + 1 + 5 + 5, exp.line_adds);
-	cl_assert(exp.line_dels == 7 + 1);
+	cl_assert_equal_i(7 + 1, exp.line_dels);
 
 	git_diff_list_free(diff);
 	diff = NULL;
@@ -61,17 +61,17 @@ void test_diff_tree__0(void)
 	cl_git_pass(git_diff_foreach(
 		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(exp.files == 2);
+	cl_assert_equal_i(2, exp.files);
-	cl_assert(exp.file_adds == 0);
+	cl_assert_equal_i(0, exp.file_adds);
-	cl_assert(exp.file_dels == 0);
+	cl_assert_equal_i(0, exp.file_dels);
-	cl_assert(exp.file_mods == 2);
+	cl_assert_equal_i(2, exp.file_mods);
 
-	cl_assert(exp.hunks == 2);
+	cl_assert_equal_i(2, exp.hunks);
 
-	cl_assert(exp.lines == 8 + 15);
+	cl_assert_equal_i(8 + 15, exp.lines);
-	cl_assert(exp.line_ctxt == 1);
+	cl_assert_equal_i(1, exp.line_ctxt);
-	cl_assert(exp.line_adds == 1);
+	cl_assert_equal_i(1, exp.line_adds);
-	cl_assert(exp.line_dels == 7 + 14);
+	cl_assert_equal_i(7 + 14, exp.line_dels);
 
 	git_diff_list_free(diff);
 
@@ -192,17 +192,17 @@ void test_diff_tree__bare(void)
 	cl_git_pass(git_diff_foreach(
 		diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(exp.files == 3);
+	cl_assert_equal_i(3, exp.files);
-	cl_assert(exp.file_adds == 2);
+	cl_assert_equal_i(2, exp.file_adds);
-	cl_assert(exp.file_dels == 0);
+	cl_assert_equal_i(0, exp.file_dels);
-	cl_assert(exp.file_mods == 1);
+	cl_assert_equal_i(1, exp.file_mods);
 
-	cl_assert(exp.hunks == 3);
+	cl_assert_equal_i(3, exp.hunks);
 
-	cl_assert(exp.lines == 4);
+	cl_assert_equal_i(4, exp.lines);
-	cl_assert(exp.line_ctxt == 0);
+	cl_assert_equal_i(0, exp.line_ctxt);
-	cl_assert(exp.line_adds == 3);
+	cl_assert_equal_i(3, exp.line_adds);
-	cl_assert(exp.line_dels == 1);
+	cl_assert_equal_i(1, exp.line_dels);
 
 	git_diff_list_free(diff);
 	git_tree_free(a);
@@ -242,17 +242,17 @@ void test_diff_tree__merge(void)
 	cl_git_pass(git_diff_foreach(
 		diff1, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
-	cl_assert(exp.files == 6);
+	cl_assert_equal_i(6, exp.files);
-	cl_assert(exp.file_adds == 2);
+	cl_assert_equal_i(2, exp.file_adds);
-	cl_assert(exp.file_dels == 1);
+	cl_assert_equal_i(1, exp.file_dels);
-	cl_assert(exp.file_mods == 3);
+	cl_assert_equal_i(3, exp.file_mods);
 
-	cl_assert(exp.hunks == 6);
+	cl_assert_equal_i(6, exp.hunks);
 
-	cl_assert(exp.lines == 59);
+	cl_assert_equal_i(59, exp.lines);
-	cl_assert(exp.line_ctxt == 1);
+	cl_assert_equal_i(1, exp.line_ctxt);
-	cl_assert(exp.line_adds == 36);
+	cl_assert_equal_i(36, exp.line_adds);
-	cl_assert(exp.line_dels == 22);
+	cl_assert_equal_i(22, exp.line_dels);
 
 	git_diff_list_free(diff1);
 }

tests-clar/diff/workdir.c

@@ -17,6 +17,7 @@ void test_diff_workdir__to_index(void)
 	git_diff_options opts = {0};
 	git_diff_list *diff = NULL;
 	diff_expects exp;
+	int use_iterator;
 
 	g_repo = cl_git_sandbox_init("status");
 
@@ -24,10 +25,15 @@ void test_diff_workdir__to_index(void)
 	opts.interhunk_lines = 1;
 	opts.flags |= GIT_DIFF_INCLUDE_IGNORED | GIT_DIFF_INCLUDE_UNTRACKED;
 
-	memset(&exp, 0, sizeof(exp));
-
 	cl_git_pass(git_diff_workdir_to_index(g_repo, &opts, &diff));
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
+		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
@@ -51,6 +57,7 @@ void test_diff_workdir__to_index(void)
 		cl_assert_equal_i(5, exp.line_ctxt);
 		cl_assert_equal_i(4, exp.line_adds);
 		cl_assert_equal_i(5, exp.line_dels);
+	}
 
 	git_diff_list_free(diff);
 }
@@ -65,6 +72,7 @@ void test_diff_workdir__to_tree(void)
 	git_diff_list *diff = NULL;
 	git_diff_list *diff2 = NULL;
 	diff_expects exp;
+	int use_iterator;
 
 	g_repo = cl_git_sandbox_init("status");
 
@@ -75,8 +83,6 @@ void test_diff_workdir__to_tree(void)
 	opts.interhunk_lines = 1;
 	opts.flags |= GIT_DIFF_INCLUDE_IGNORED | GIT_DIFF_INCLUDE_UNTRACKED;
 
-	memset(&exp, 0, sizeof(exp));
-
 	/* You can't really generate the equivalent of git_diff_workdir_to_tree()
 	 * using C git.  It really wants to interpose the index into the diff.
 	 *
@@ -89,6 +95,13 @@ void test_diff_workdir__to_tree(void)
 	 */
 	cl_git_pass(git_diff_workdir_to_tree(g_repo, &opts, a, &diff));
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
+		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
@@ -98,6 +111,7 @@ void test_diff_workdir__to_tree(void)
 		cl_assert_equal_i(4, exp.file_mods);
 		cl_assert_equal_i(1, exp.file_ignored);
 		cl_assert_equal_i(5, exp.file_untracked);
+	}
 
 	/* Since there is no git diff equivalent, let's just assume that the
 	 * text diffs produced by git_diff_foreach are accurate here.  We will
@@ -117,6 +131,13 @@ void test_diff_workdir__to_tree(void)
 	cl_git_pass(git_diff_merge(diff, diff2));
 	git_diff_list_free(diff2);
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
+		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
@@ -133,6 +154,7 @@ void test_diff_workdir__to_tree(void)
 		cl_assert_equal_i(4, exp.line_ctxt);
 		cl_assert_equal_i(8, exp.line_adds);
 		cl_assert_equal_i(5, exp.line_dels);
+	}
 
 	git_diff_list_free(diff);
 	diff = NULL;
@@ -146,6 +168,13 @@ void test_diff_workdir__to_tree(void)
 	cl_git_pass(git_diff_merge(diff, diff2));
 	git_diff_list_free(diff2);
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
+		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
 
@@ -162,6 +191,7 @@ void test_diff_workdir__to_tree(void)
 		cl_assert_equal_i(3, exp.line_ctxt);
 		cl_assert_equal_i(12, exp.line_adds);
 		cl_assert_equal_i(4, exp.line_dels);
+	}
 
 	git_diff_list_free(diff);
 
@@ -175,6 +205,7 @@ void test_diff_workdir__to_index_with_pathspec(void)
 	git_diff_list *diff = NULL;
 	diff_expects exp;
 	char *pathspec = NULL;
+	int use_iterator;
 
 	g_repo = cl_git_sandbox_init("status");
 
@@ -184,9 +215,15 @@ void test_diff_workdir__to_index_with_pathspec(void)
 	opts.pathspec.strings = &pathspec;
 	opts.pathspec.count   = 1;
 
+	cl_git_pass(git_diff_workdir_to_index(g_repo, &opts, &diff));
+
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
 		memset(&exp, 0, sizeof(exp));
 
-	cl_git_pass(git_diff_workdir_to_index(g_repo, &opts, &diff));
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, NULL, NULL));
+		else
 			cl_git_pass(git_diff_foreach(diff, &exp, diff_file_fn, NULL, NULL));
 
 		cl_assert_equal_i(13, exp.files);
@@ -195,13 +232,21 @@ void test_diff_workdir__to_index_with_pathspec(void)
 		cl_assert_equal_i(4, exp.file_mods);
 		cl_assert_equal_i(1, exp.file_ignored);
 		cl_assert_equal_i(4, exp.file_untracked);
+	}
 
 	git_diff_list_free(diff);
 
-	memset(&exp, 0, sizeof(exp));
 	pathspec = "modified_file";
 
 	cl_git_pass(git_diff_workdir_to_index(g_repo, &opts, &diff));
+
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
+		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, NULL, NULL));
+		else
 			cl_git_pass(git_diff_foreach(diff, &exp, diff_file_fn, NULL, NULL));
 
 		cl_assert_equal_i(1, exp.files);
@@ -210,13 +255,21 @@ void test_diff_workdir__to_index_with_pathspec(void)
 		cl_assert_equal_i(1, exp.file_mods);
 		cl_assert_equal_i(0, exp.file_ignored);
 		cl_assert_equal_i(0, exp.file_untracked);
+	}
 
 	git_diff_list_free(diff);
 
-	memset(&exp, 0, sizeof(exp));
 	pathspec = "subdir";
 
 	cl_git_pass(git_diff_workdir_to_index(g_repo, &opts, &diff));
+
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
+		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, NULL, NULL));
+		else
 			cl_git_pass(git_diff_foreach(diff, &exp, diff_file_fn, NULL, NULL));
 
 		cl_assert_equal_i(3, exp.files);
@@ -225,13 +278,21 @@ void test_diff_workdir__to_index_with_pathspec(void)
 		cl_assert_equal_i(1, exp.file_mods);
 		cl_assert_equal_i(0, exp.file_ignored);
 		cl_assert_equal_i(1, exp.file_untracked);
+	}
 
 	git_diff_list_free(diff);
 
-	memset(&exp, 0, sizeof(exp));
 	pathspec = "*_deleted";
 
 	cl_git_pass(git_diff_workdir_to_index(g_repo, &opts, &diff));
+
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
+		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, NULL, NULL));
+		else
 			cl_git_pass(git_diff_foreach(diff, &exp, diff_file_fn, NULL, NULL));
 
 		cl_assert_equal_i(2, exp.files);
@@ -240,6 +301,7 @@ void test_diff_workdir__to_index_with_pathspec(void)
 		cl_assert_equal_i(0, exp.file_mods);
 		cl_assert_equal_i(0, exp.file_ignored);
 		cl_assert_equal_i(0, exp.file_untracked);
+	}
 
 	git_diff_list_free(diff);
 }
@@ -249,6 +311,7 @@ void test_diff_workdir__filemode_changes(void)
 	git_config *cfg;
 	git_diff_list *diff = NULL;
 	diff_expects exp;
+	int use_iterator;
 
 	if (!cl_is_chmod_supported())
 		return;
@@ -262,13 +325,20 @@ void test_diff_workdir__filemode_changes(void)
 
 	cl_git_pass(git_diff_workdir_to_index(g_repo, NULL, &diff));
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
 		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				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.hunks);
+	}
 
 	git_diff_list_free(diff);
 
@@ -278,13 +348,20 @@ void test_diff_workdir__filemode_changes(void)
 
 	cl_git_pass(git_diff_workdir_to_index(g_repo, NULL, &diff));
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
 		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				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(0, exp.hunks);
+	}
 
 	git_diff_list_free(diff);
 
@@ -347,6 +424,7 @@ void test_diff_workdir__head_index_and_workdir_all_differ(void)
 	diff_expects exp;
 	char *pathspec = "staged_changes_modified_file";
 	git_tree *tree;
+	int use_iterator;
 
 	/* For this file,
 	 * - head->index diff has 1 line of context, 1 line of diff
@@ -366,9 +444,16 @@ void test_diff_workdir__head_index_and_workdir_all_differ(void)
 	cl_git_pass(git_diff_index_to_tree(g_repo, &opts, tree, &diff_i2t));
 	cl_git_pass(git_diff_workdir_to_index(g_repo, &opts, &diff_w2i));
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
 		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff_i2t, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				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);
@@ -378,10 +463,18 @@ void test_diff_workdir__head_index_and_workdir_all_differ(void)
 		cl_assert_equal_i(1, exp.line_ctxt);
 		cl_assert_equal_i(1, exp.line_adds);
 		cl_assert_equal_i(0, exp.line_dels);
+	}
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
 		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff_w2i, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				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);
@@ -391,12 +484,20 @@ void test_diff_workdir__head_index_and_workdir_all_differ(void)
 		cl_assert_equal_i(2, exp.line_ctxt);
 		cl_assert_equal_i(1, exp.line_adds);
 		cl_assert_equal_i(0, exp.line_dels);
+	}
 
 	cl_git_pass(git_diff_merge(diff_i2t, diff_w2i));
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
 		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff_i2t, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				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);
@@ -406,6 +507,7 @@ void test_diff_workdir__head_index_and_workdir_all_differ(void)
 		cl_assert_equal_i(1, exp.line_ctxt);
 		cl_assert_equal_i(2, exp.line_adds);
 		cl_assert_equal_i(0, exp.line_dels);
+	}
 
 	git_diff_list_free(diff_i2t);
 	git_diff_list_free(diff_w2i);
@@ -419,6 +521,7 @@ void test_diff_workdir__eof_newline_changes(void)
 	git_diff_list *diff = NULL;
 	diff_expects exp;
 	char *pathspec = "current_file";
+	int use_iterator;
 
 	g_repo = cl_git_sandbox_init("status");
 
@@ -427,9 +530,16 @@ void test_diff_workdir__eof_newline_changes(void)
 
 	cl_git_pass(git_diff_workdir_to_index(g_repo, &opts, &diff));
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
 		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				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);
@@ -439,6 +549,7 @@ void test_diff_workdir__eof_newline_changes(void)
 		cl_assert_equal_i(0, exp.line_ctxt);
 		cl_assert_equal_i(0, exp.line_adds);
 		cl_assert_equal_i(0, exp.line_dels);
+	}
 
 	git_diff_list_free(diff);
 
@@ -446,9 +557,16 @@ void test_diff_workdir__eof_newline_changes(void)
 
 	cl_git_pass(git_diff_workdir_to_index(g_repo, &opts, &diff));
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
 		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				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);
@@ -458,6 +576,7 @@ void test_diff_workdir__eof_newline_changes(void)
 		cl_assert_equal_i(1, exp.line_ctxt);
 		cl_assert_equal_i(1, exp.line_adds);
 		cl_assert_equal_i(0, exp.line_dels);
+	}
 
 	git_diff_list_free(diff);
 
@@ -465,9 +584,16 @@ void test_diff_workdir__eof_newline_changes(void)
 
 	cl_git_pass(git_diff_workdir_to_index(g_repo, &opts, &diff));
 
+	for (use_iterator = 0; use_iterator <= 1; use_iterator++) {
 		memset(&exp, 0, sizeof(exp));
+
+		if (use_iterator)
+			cl_git_pass(diff_foreach_via_iterator(
+				diff, &exp, diff_file_fn, diff_hunk_fn, diff_line_fn));
+		else
 			cl_git_pass(git_diff_foreach(
 				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);
@@ -477,6 +603,7 @@ void test_diff_workdir__eof_newline_changes(void)
 		cl_assert_equal_i(0, exp.line_ctxt);
 		cl_assert_equal_i(1, exp.line_adds);
 		cl_assert_equal_i(2, exp.line_dels);
+	}
 
 	git_diff_list_free(diff);
 }