difftool: prepare "diff" cmdline in cmd_difftool()

We call into either run_dir_diff() or run_file_diff(), each of which sets up a child argv starting with "diff" and some hard-coded options (depending on which mode we're using). Let's extract that logic into the caller, which will make it easier to modify the options for cases which affect both functions. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jeff King committed Sep 13, 2021 at 05:35 UTC b4c7aab7b9fa7f97c6328751b2cc429189b08514
1 file changed +7 -8
builtin/difftool.c
+7 -8
@@ -331,7 +331,6 @@ static int checkout_path(unsigned mode, struct object_id *oid,
331 }
332
333 static int run_dir_diff(const char *extcmd, int symlinks, const char *prefix,
334 - int argc, const char **argv,
334 struct child_process *child)
335 {
336 char tmpdir[PATH_MAX];
@@ -393,10 +392,6 @@ static int run_dir_diff(const char *extcmd, int symlinks, const char *prefix,
392 child->clean_on_exit = 1;
393 child->dir = prefix;
394 child->out = -1;
396 - strvec_pushl(&child->args, "diff", "--raw", "--no-abbrev", "-z",
397 - NULL);
398 - for (i = 0; i < argc; i++)
399 - strvec_push(&child->args, argv[i]);
395 if (start_command(child))
396 die("could not obtain raw diff");
397 fp = xfdopen(child->out, "r");
@@ -683,7 +678,6 @@ static int run_file_diff(int prompt, const char *prefix,
678 env[2] = "GIT_DIFFTOOL_NO_PROMPT=true";
679
680
686 - strvec_push(&args, "diff");
681 for (i = 0; i < argc; i++)
682 strvec_push(&args, argv[i]);
683 return run_command_v_opt_cd_env(args.v, RUN_GIT_CMD, prefix, env);
@@ -769,7 +763,12 @@ int cmd_difftool(int argc, const char **argv, const char *prefix)
763 * will invoke a separate instance of 'git-difftool--helper' for
764 * each file that changed.
765 */
766 + strvec_push(&child.args, "diff");
767 + if (dir_diff)
768 + strvec_pushl(&child.args, "--raw", "--no-abbrev", "-z", NULL);
769 + strvec_pushv(&child.args, argv);
770 +
771 if (dir_diff)
773 - return run_dir_diff(extcmd, symlinks, prefix, argc, argv, &child);
774 - return run_file_diff(prompt, prefix, argc, argv);
772 + return run_dir_diff(extcmd, symlinks, prefix, &child);
773 + return run_file_diff(prompt, prefix, child.args.nr, child.args.v);
774 }