Fix problems in diff iterator record chaining

There is a bug in building the linked list of line records in the
diff iterator and also an off by one element error in the hunk
counts.  This fixes both of these, adds some test data with more
complex sets of hunk and line diffs to exercise this code better.

1 files changed, 82 insertions, 0 deletions

diff --git a/tests-clar/diff/tree.c b/tests-clar/diff/tree.c
index 3003374a5..f5e72cadc 100644
--- a/tests-clar/diff/tree.c
+++ b/tests-clar/diff/tree.c
@@ -256,3 +256,85 @@ void test_diff_tree__merge(void)
 
 	git_diff_list_free(diff1);
 }
+
+void test_diff_tree__larger_hunks(void)
+{
+	const char *a_commit = "d70d245ed97ed2aa596dd1af6536e4bfdb047b69";
+	const char *b_commit = "7a9e0b02e63179929fed24f0a3e0f19168114d10";
+	git_tree *a, *b;
+	git_diff_options opts = {0};
+	git_diff_list *diff = NULL;
+	git_diff_iterator *iter = NULL;
+	git_diff_delta *delta;
+	diff_expects exp;
+	int error, num_files = 0;
+
+	g_repo = cl_git_sandbox_init("diff");
+
+	cl_assert((a = resolve_commit_oid_to_tree(g_repo, a_commit)) != NULL);
+	cl_assert((b = resolve_commit_oid_to_tree(g_repo, b_commit)) != NULL);
+
+	opts.context_lines = 1;
+	opts.interhunk_lines = 0;
+
+	memset(&exp, 0, sizeof(exp));
+
+	cl_git_pass(git_diff_tree_to_tree(g_repo, &opts, a, b, &diff));
+	cl_git_pass(git_diff_iterator_new(&iter, diff));
+
+	/* this should be exact */
+	cl_assert(git_diff_iterator_progress(iter) == 0.0f);
+
+	/* You wouldn't actually structure an iterator loop this way, but
+	 * I have here for testing purposes of the return value
+	 */
+	while (!(error = git_diff_iterator_next_file(&delta, iter))) {
+		git_diff_range *range;
+		const char *header;
+		size_t header_len;
+		int actual_hunks = 0, num_hunks;
+		float expected_progress;
+
+		num_files++;
+
+		expected_progress = (float)num_files / 2.0f;
+		cl_assert(expected_progress == git_diff_iterator_progress(iter));
+
+		num_hunks = git_diff_iterator_num_hunks_in_file(iter);
+
+		while (!(error = git_diff_iterator_next_hunk(
+					&range, &header, &header_len, iter)))
+		{
+			int actual_lines = 0;
+			int num_lines = git_diff_iterator_num_lines_in_hunk(iter);
+			char origin;
+			const char *line;
+			size_t line_len;
+
+			while (!(error = git_diff_iterator_next_line(
+						&origin, &line, &line_len, iter)))
+			{
+				actual_lines++;
+			}
+
+			cl_assert_equal_i(GIT_ITEROVER, error);
+			cl_assert_equal_i(actual_lines, num_lines);
+
+			actual_hunks++;
+		}
+
+		cl_assert_equal_i(GIT_ITEROVER, error);
+		cl_assert_equal_i(actual_hunks, num_hunks);
+	}
+
+	cl_assert_equal_i(GIT_ITEROVER, error);
+	cl_assert_equal_i(2, num_files);
+	cl_assert(git_diff_iterator_progress(iter) == 1.0f);
+
+	git_diff_iterator_free(iter);
+	git_diff_list_free(diff);
+	diff = NULL;
+
+	git_tree_free(a);
+	git_tree_free(b);
+}