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

Author: gitster

builtin.h

@@ -41,6 +41,8 @@ int copy_note_for_rewrite(struct notes_rewrite_cfg *c,
 void finish_copy_notes_for_rewrite(struct notes_rewrite_cfg *c);
 
 extern int check_pager_config(const char *cmd);
+struct diff_options;
+extern void setup_diff_pager(struct diff_options *);
 
 extern int textconv_object(const char *path, unsigned mode, const unsigned char *sha1, char **buf, unsigned long *buf_size);
 

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();
+}

diff-no-index.c

@@ -224,13 +224,6 @@ void diff_no_index(struct rev_info *revs,
 		}
 	}
 
-	/*
-	 * 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(&revs->diffopt, EXIT_WITH_STATUS))
-		setup_pager();
-
 	if (prefix) {
 		int len = strlen(prefix);
 		const char *paths[3];
@@ -255,13 +248,15 @@ void diff_no_index(struct rev_info *revs,
 	if (!revs->diffopt.output_format)
 		revs->diffopt.output_format = DIFF_FORMAT_PATCH;
 
-	DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
 	DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
 
 	revs->max_count = -2;
 	if (diff_setup_done(&revs->diffopt) < 0)
 		die("diff_setup_done failed");
 
+	setup_diff_pager(&revs->diffopt);
+	DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
+
 	if (queue_diff(&revs->diffopt, revs->diffopt.pathspec.raw[0],
 		       revs->diffopt.pathspec.raw[1]))
 		exit(1);