Add git_diff_patch_to_str API

This adds an API to generate a complete single-file patch text
from a git_diff_patch object.

1 files changed, 99 insertions, 0 deletions

diff --git a/tests-clar/diff/diffiter.c b/tests-clar/diff/diffiter.c
index f6d9bfc38..86e8d1f57 100644
--- a/tests-clar/diff/diffiter.c
+++ b/tests-clar/diff/diffiter.c
@@ -342,3 +342,102 @@ void test_diff_diffiter__iterate_randomly_while_saving_state(void)
 	cl_assert_equal_i(8, exp.hunks);
 	cl_assert_equal_i(14, exp.lines);
 }
+
+/* This output is taken directly from `git diff` on the status test data */
+static const char *expected_patch_text[8] = {
+	/* 0 */
+	"diff --git a/file_deleted b/file_deleted\n"
+	"deleted file mode 100644\n"
+	"index 5452d32..0000000\n"
+	"--- a/file_deleted\n"
+	"+++ /dev/null\n"
+	"@@ -1 +0,0 @@\n"
+	"-file_deleted\n",
+	/* 1 */
+	"diff --git a/modified_file b/modified_file\n"
+	"index 452e424..0a53963 100644\n"
+	"--- a/modified_file\n"
+	"+++ b/modified_file\n"
+	"@@ -1 +1,2 @@\n"
+	" modified_file\n"
+	"+modified_file\n",
+	/* 2 */
+	"diff --git a/staged_changes_file_deleted b/staged_changes_file_deleted\n"
+	"deleted file mode 100644\n"
+	"index a6be623..0000000\n"
+	"--- a/staged_changes_file_deleted\n"
+	"+++ /dev/null\n"
+	"@@ -1,2 +0,0 @@\n"
+	"-staged_changes_file_deleted\n"
+	"-staged_changes_file_deleted\n",
+	/* 3 */
+	"diff --git a/staged_changes_modified_file b/staged_changes_modified_file\n"
+	"index 906ee77..011c344 100644\n"
+	"--- a/staged_changes_modified_file\n"
+	"+++ b/staged_changes_modified_file\n"
+	"@@ -1,2 +1,3 @@\n"
+	" staged_changes_modified_file\n"
+	" staged_changes_modified_file\n"
+	"+staged_changes_modified_file\n",
+	/* 4 */
+	"diff --git a/staged_new_file_deleted_file b/staged_new_file_deleted_file\n"
+	"deleted file mode 100644\n"
+	"index 90b8c29..0000000\n"
+	"--- a/staged_new_file_deleted_file\n"
+	"+++ /dev/null\n"
+	"@@ -1 +0,0 @@\n"
+	"-staged_new_file_deleted_file\n",
+	/* 5 */
+	"diff --git a/staged_new_file_modified_file b/staged_new_file_modified_file\n"
+	"index ed06290..8b090c0 100644\n"
+	"--- a/staged_new_file_modified_file\n"
+	"+++ b/staged_new_file_modified_file\n"
+	"@@ -1 +1,2 @@\n"
+	" staged_new_file_modified_file\n"
+	"+staged_new_file_modified_file\n",
+	/* 6 */
+	"diff --git a/subdir/deleted_file b/subdir/deleted_file\n"
+	"deleted file mode 100644\n"
+	"index 1888c80..0000000\n"
+	"--- a/subdir/deleted_file\n"
+	"+++ /dev/null\n"
+	"@@ -1 +0,0 @@\n"
+	"-subdir/deleted_file\n",
+	/* 7 */
+	"diff --git a/subdir/modified_file b/subdir/modified_file\n"
+	"index a619198..57274b7 100644\n"
+	"--- a/subdir/modified_file\n"
+	"+++ b/subdir/modified_file\n"
+	"@@ -1 +1,2 @@\n"
+	" subdir/modified_file\n"
+	"+subdir/modified_file\n"
+};
+
+void test_diff_diffiter__iterate_and_generate_patch_text(void)
+{
+	git_repository *repo = cl_git_sandbox_init("status");
+	git_diff_list *diff;
+	size_t d, num_d;
+
+	cl_git_pass(git_diff_workdir_to_index(repo, NULL, &diff));
+
+	num_d = git_diff_num_deltas(diff);
+	cl_assert_equal_i(8, (int)num_d);
+
+	for (d = 0; d < num_d; ++d) {
+		git_diff_patch *patch;
+		char *text;
+
+		cl_git_pass(git_diff_get_patch(&patch, NULL, diff, d));
+		cl_assert(patch != NULL);
+
+		cl_git_pass(git_diff_patch_to_str(&text, patch));
+
+		cl_assert_equal_s(expected_patch_text[d], text);
+
+		git__free(text);
+		git_diff_patch_free(patch);
+	}
+
+	git_diff_list_free(diff);
+}