blame: add option to ignore whitespace changes

Author: CarlSchwan

include/git2/blame.h

@@ -47,6 +47,8 @@ typedef enum {
 	 * to canonical real names and email addresses. The mailmap will be read
 	 * from the working directory, or HEAD in a bare repository. */
 	GIT_BLAME_USE_MAILMAP = (1<<5),
+	/** Ignore whitespace differences */
+	GIT_BLAME_IGNORE_WHITESPACE = (1<<6),
 } git_blame_flag_t;
 
 /**

src/blame_git.c

@@ -365,11 +365,14 @@ static void trim_common_tail(mmfile_t *a, mmfile_t *b, long ctx)
 	b->size -= trimmed - recovered;
 }
 
-static int diff_hunks(mmfile_t file_a, mmfile_t file_b, void *cb_data)
+static int diff_hunks(mmfile_t file_a, mmfile_t file_b, void *cb_data, git_blame_options *options)
 {
-	xpparam_t xpp = {0};
 	xdemitconf_t xecfg = {0};
 	xdemitcb_t ecb = {0};
+	xpparam_t xpp = {0};
+
+	if (options->flags & GIT_BLAME_IGNORE_WHITESPACE)
+		xpp.flags |= XDF_IGNORE_WHITESPACE;
 
 	xecfg.hunk_func = my_emit;
 	ecb.priv = cb_data;
@@ -409,7 +412,7 @@ static int pass_blame_to_parent(
 	fill_origin_blob(parent, &file_p);
 	fill_origin_blob(target, &file_o);
 
-	if (diff_hunks(file_p, file_o, &d) < 0)
+	if (diff_hunks(file_p, file_o, &d, &blame->options) < 0)
 		return -1;
 
 	/* The reset (i.e. anything after tlno) are the same as the parent */

tests/blame/simple.c

@@ -238,6 +238,24 @@ void test_blame_simple__can_restrict_lines_min(void)
 	check_blame_hunk_index(g_repo, g_blame, 1, 11, 5, 0, "aa06ecca", "b.txt");
 }
 
+/*
+ * $ git blame -n c.txt
+ *    orig line no                          final line no
+ * commit    V  author      timestamp                  V
+ * 702c7aa5  1 (Carl Schwan 2020-01-29 01:52:31 +0100  4
+ */
+void test_blame_simple__can_ignore_whitespace_change(void)
+{
+	git_blame_options opts = GIT_BLAME_OPTIONS_INIT;
+
+	cl_git_pass(git_repository_open(&g_repo, cl_fixture("blametest.git")));
+
+	opts.flags |= GIT_BLAME_IGNORE_WHITESPACE;
+	cl_git_pass(git_blame_file(&g_blame, g_repo, "c.txt", &opts));
+	cl_assert_equal_i(1, git_blame_get_hunk_count(g_blame));
+	check_blame_hunk_index(g_repo, g_blame, 0,  1, 4, 0, "702c7aa5", "c.txt");
+}
+
 /*
  * $ git blame -n b.txt -L ,6
  *    orig line no                          final line no