Merge branch 'jk/diff-no-index-pager' into maint

"git diff --no-index" did not work with pagers correctly.

* jk/diff-no-index-pager:
  do not run pager with diff --no-index --quiet
  fix pager.diff with diff --no-index

1 files changed, 17 insertions, 7 deletions

diff --git a/builtin/diff.c b/builtin/diff.c
index 9069dc41be..da8f6aac2b 100644
--- a/builtin/diff.c
+++ b/builtin/diff.c
@@ -304,13 +304,7 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
 
 	DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
 
-	/*
-	 * If the user asked for our exit code then don't start a
-	 * pager or we would end up reporting its exit code instead.
-	 */
-	if (!DIFF_OPT_TST(&rev.diffopt, EXIT_WITH_STATUS) &&
-	    check_pager_config("diff") != 0)
-		setup_pager();
+	setup_diff_pager(&rev.diffopt);
 
 	/*
 	 * Do we have --cached and not have a pending object, then
@@ -421,3 +415,19 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
 		refresh_index_quietly();
 	return result;
 }
+
+void setup_diff_pager(struct diff_options *opt)
+{
+	/*
+	 * If the user asked for our exit code, then either they want --quiet
+	 * or --exit-code. We should definitely not bother with a pager in the
+	 * former case, as we will generate no output. Since we still properly
+	 * report our exit code even when a pager is run, we _could_ run a
+	 * pager with --exit-code. But since we have not done so historically,
+	 * and because it is easy to find people oneline advising "git diff
+	 * --exit-code" in hooks and other scripts, we do not do so.
+	 */
+	if (!DIFF_OPT_TST(opt, EXIT_WITH_STATUS) &&
+	    check_pager_config("diff") != 0)
+		setup_pager();
+}