fix pager.diff with diff --no-index

git-diff does not rely on the git wrapper to setup its
pager; instead, it sets it up on its own after seeing
whether --quiet or --exit-code has been specified.  After
diff_no_index was split off from cmd_diff, commit b3fde6c
(git diff --no-index: default to page like other diff
frontends, 2008-05-26) duplicated the one-liner from
cmd_diff to turn on the pager.

Later, commit 8f0359f (Allow pager of diff command be
enabled/disabled, 2008-07-21) taught the the version in
cmd_diff to respect the pager.diff config, but the version
in diff_no_index was left behind. This meant that

  git -c pager.diff=0 diff a b

would not use a pager, but

  git -c pager.diff=0 diff --no-index a b

would.  Let's fix it by factoring out a common function.

While we're there, let's update the antiquated comment,
which claims that the pager interferes with propagating the
exit code; this has not been the case since ea27a18 (spawn
pager via run_command interface, 2008-07-22).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin.h b/builtin.h
index 857b9c8aa85fff5764b528485a880cd9dfa95b17..999ba3be7cea2197ed0c0dba7c5823b01fec9906 100644 (file)
--- a/builtin.h
+++ b/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);
 

diff --git a/builtin/diff.c b/builtin/diff.c
index 9069dc41be33a362ff04d52c00b4830eed272826..da8f6aac2bde9bb93cb059898a21c19c9bb27634 100644 (file)
--- 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();
+}

diff --git a/diff-no-index.c b/diff-no-index.c
index f0b0010aedd67f9b34f43426c47e837dfe2a522b..fc1decdf38a7649f37f410947d343436061aa8a0 100644 (file)
--- a/diff-no-index.c
+++ b/diff-no-index.c
@@ -224,12 +224,7 @@ 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();
+       setup_diff_pager(&revs->diffopt);
 
        if (prefix) {
                int len = strlen(prefix);