Allow git-diff exit with codes similar to diff(1)

This introduces a new command-line option: --exit-code. The diff
programs will return 1 for differences, return 0 for equality, and
something else for errors.

Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt
index d8696b7b36ff81f47214da9d7c4ec53142b97653..77a3f78dd75514667b77ae4e1dbbb3731b05a33d 100644 (file)
--- a/Documentation/diff-options.txt
+++ b/Documentation/diff-options.txt
@@ -159,5 +159,10 @@
 -w::
        Shorthand for "--ignore-all-space".
 
+--exit-code::
+       Make the program exit with codes similar to diff(1).
+       That is, it exits with 1 if there were differences and
+       0 means no differences.
+
 For more detailed explanation on these common options, see also
 link:diffcore.html[diffcore documentation].

diff --git a/builtin-diff-files.c b/builtin-diff-files.c
index aec83384298042fc4509605299f82e82745ae675..6ba5077a2be6619f110280622cf46a7f4cfb8b01 100644 (file)
--- a/builtin-diff-files.c
+++ b/builtin-diff-files.c
@@ -17,6 +17,7 @@ int cmd_diff_files(int argc, const char **argv, const char *prefix)
 {
        struct rev_info rev;
        int nongit = 0;
+       int result;
 
        prefix = setup_git_directory_gently(&nongit);
        init_revisions(&rev, prefix);
@@ -29,5 +30,6 @@ int cmd_diff_files(int argc, const char **argv, const char *prefix)
                argc = setup_revisions(argc, argv, &rev, NULL);
        if (!rev.diffopt.output_format)
                rev.diffopt.output_format = DIFF_FORMAT_RAW;
-       return run_diff_files_cmd(&rev, argc, argv);
+       result = run_diff_files_cmd(&rev, argc, argv);
+       return rev.diffopt.exit_with_status ? rev.diffopt.has_changes: result;
 }

diff --git a/builtin-diff-index.c b/builtin-diff-index.c
index 083599d5c4c174cfab7c148428630534e4cd8174..d90eba95a6be17bd0486e0311c2657b1f69ab7d9 100644 (file)
--- a/builtin-diff-index.c
+++ b/builtin-diff-index.c
@@ -14,6 +14,7 @@ int cmd_diff_index(int argc, const char **argv, const char *prefix)
        struct rev_info rev;
        int cached = 0;
        int i;
+       int result;
 
        init_revisions(&rev, prefix);
        git_config(git_default_config); /* no "diff" UI options */
@@ -42,5 +43,6 @@ int cmd_diff_index(int argc, const char **argv, const char *prefix)
                perror("read_cache");
                return -1;
        }
-       return run_diff_index(&rev, cached);
+       result = run_diff_index(&rev, cached);
+       return rev.diffopt.exit_with_status ? rev.diffopt.has_changes: result;
 }

diff --git a/builtin-diff-tree.c b/builtin-diff-tree.c
index 24cb2d7f84064d7833fa04f33aeca6eafc8b931d..0b591c87169ff4b8c2173bedb26d6ed1a8a84b68 100644 (file)
--- a/builtin-diff-tree.c
+++ b/builtin-diff-tree.c
@@ -118,7 +118,8 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix)
        }
 
        if (!read_stdin)
-               return 0;
+               return opt->diffopt.exit_with_status ?
+                   opt->diffopt.has_changes: 0;
 
        if (opt->diffopt.detect_rename)
                opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
@@ -133,5 +134,5 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix)
                else
                        diff_tree_stdin(line);
        }
-       return 0;
+       return opt->diffopt.exit_with_status ? opt->diffopt.has_changes: 0;
 }

diff --git a/builtin-diff.c b/builtin-diff.c
index 4efbb8237bd49e8717a42833b2d9b2db064b45ac..21d13f0b30359295b8385754fccb4bb71f995dba 100644 (file)
--- a/builtin-diff.c
+++ b/builtin-diff.c
@@ -190,6 +190,7 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
        const char *path = NULL;
        struct blobinfo blob[2];
        int nongit = 0;
+       int result = 0;
 
        /*
         * We could get N tree-ish in the rev.pending_objects list.
@@ -292,17 +293,17 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
        if (!ents) {
                switch (blobs) {
                case 0:
-                       return run_diff_files_cmd(&rev, argc, argv);
+                       result = run_diff_files_cmd(&rev, argc, argv);
                        break;
                case 1:
                        if (paths != 1)
                                usage(builtin_diff_usage);
-                       return builtin_diff_b_f(&rev, argc, argv, blob, path);
+                       result = builtin_diff_b_f(&rev, argc, argv, blob, path);
                        break;
                case 2:
                        if (paths)
                                usage(builtin_diff_usage);
-                       return builtin_diff_blobs(&rev, argc, argv, blob);
+                       result = builtin_diff_blobs(&rev, argc, argv, blob);
                        break;
                default:
                        usage(builtin_diff_usage);
@@ -311,19 +312,21 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
        else if (blobs)
                usage(builtin_diff_usage);
        else if (ents == 1)
-               return builtin_diff_index(&rev, argc, argv);
+               result = builtin_diff_index(&rev, argc, argv);
        else if (ents == 2)
-               return builtin_diff_tree(&rev, argc, argv, ent);
+               result = builtin_diff_tree(&rev, argc, argv, ent);
        else if ((ents == 3) && (ent[0].item->flags & UNINTERESTING)) {
                /* diff A...B where there is one sane merge base between
                 * A and B.  We have ent[0] == merge-base, ent[1] == A,
                 * and ent[2] == B.  Show diff between the base and B.
                 */
                ent[1] = ent[2];
-               return builtin_diff_tree(&rev, argc, argv, ent);
+               result = builtin_diff_tree(&rev, argc, argv, ent);
        }
        else
-               return builtin_diff_combined(&rev, argc, argv,
+               result = builtin_diff_combined(&rev, argc, argv,
                                             ent, ents);
-       usage(builtin_diff_usage);
+       if (rev.diffopt.exit_with_status)
+               result = rev.diffopt.has_changes;
+       return result;
 }

diff --git a/diff-lib.c b/diff-lib.c
index 6abb981534bf032d50e28eb3a14033c1b6546762..f9a1a10cc0319270358d658cd5e83bd5633fbf49 100644 (file)
--- a/diff-lib.c
+++ b/diff-lib.c
@@ -170,8 +170,10 @@ static int handle_diff_files_args(struct rev_info *revs,
                else if (!strcmp(argv[1], "--theirs"))
                        revs->max_count = 3;
                else if (!strcmp(argv[1], "-n") ||
-                               !strcmp(argv[1], "--no-index"))
+                               !strcmp(argv[1], "--no-index")) {
                        revs->max_count = -2;
+                       revs->diffopt.exit_with_status = 1;
+               }
                else if (!strcmp(argv[1], "-q"))
                        *silent = 1;
                else
@@ -237,6 +239,7 @@ int setup_diff_no_index(struct rev_info *revs,
                        break;
                } else if (i < argc - 3 && !strcmp(argv[i], "--no-index")) {
                        i = argc - 3;
+                       revs->diffopt.exit_with_status = 1;
                        break;
                }
        if (argc != i + 2 || (!is_outside_repo(argv[i + 1], nongit, prefix) &&

diff --git a/diff.c b/diff.c
index 954ca83e0b0c95f55c0287d2deeb4cab76153fe0..cc818011b93a13c269344819f5a0045f2558d550 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -2134,6 +2134,8 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                options->color_diff = options->color_diff_words = 1;
        else if (!strcmp(arg, "--no-renames"))
                options->detect_rename = 0;
+       else if (!strcmp(arg, "--exit-code"))
+               options->exit_with_status = 1;
        else
                return 0;
        return 1;
@@ -2910,6 +2912,8 @@ void diffcore_std(struct diff_options *options)
                diffcore_order(options->orderfile);
        diff_resolve_rename_copy();
        diffcore_apply_filter(options->filter);
+       if (options->exit_with_status)
+               options->has_changes = !!diff_queued_diff.nr;
 }
 
 
@@ -2920,6 +2924,8 @@ void diffcore_std_no_resolve(struct diff_options *options)
        if (options->orderfile)
                diffcore_order(options->orderfile);
        diffcore_apply_filter(options->filter);
+       if (options->exit_with_status)
+               options->has_changes = !!diff_queued_diff.nr;
 }
 
 void diff_addremove(struct diff_options *options,

diff --git a/diff.h b/diff.h
index 4b435e8b1933222da02f9e4cf2c28d2fef44d292..d13fc89768087427379749479d172da31bff95b9 100644 (file)
--- a/diff.h
+++ b/diff.h
@@ -56,7 +56,8 @@ struct diff_options {
                 silent_on_remove:1,
                 find_copies_harder:1,
                 color_diff:1,
-                color_diff_words:1;
+                color_diff_words:1,
+                exit_with_status:1;
        int context;
        int break_opt;
        int detect_rename;
@@ -71,6 +72,8 @@ struct diff_options {
        const char *msg_sep;
        const char *stat_sep;
        long xdl_opts;
+       /* 0 - no differences; only meaningful if exit_with_status set */
+       int has_changes;
 
        int stat_width;
        int stat_name_width;

diff --git a/t/t4017-diff-retval.sh b/t/t4017-diff-retval.sh
new file mode 100755 (executable)
index 0000000..6873190
--- /dev/null
+++ b/t/t4017-diff-retval.sh
@@ -0,0 +1,79 @@
+#!/bin/sh
+
+test_description='Return value of diffs'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+       echo 1 >a &&
+       git add . &&
+       git commit -m first &&
+       echo 2 >b &&
+       git add . &&
+       git commit -a -m second
+'
+
+test_expect_success 'git diff-tree HEAD^ HEAD' '
+       git diff-tree --exit-code HEAD^ HEAD
+       test $? = 1
+'
+test_expect_success 'git diff-tree HEAD^ HEAD -- a' '
+       git diff-tree --exit-code HEAD^ HEAD -- a
+       test $? = 0
+'
+test_expect_success 'git diff-tree HEAD^ HEAD -- b' '
+       git diff-tree --exit-code HEAD^ HEAD -- b
+       test $? = 1
+'
+test_expect_success 'echo HEAD | git diff-tree --stdin' '
+       echo $(git rev-parse HEAD) | git diff-tree --exit-code --stdin
+       test $? = 1
+'
+test_expect_success 'git diff-tree HEAD HEAD' '
+       git diff-tree --exit-code HEAD HEAD
+       test $? = 0
+'
+test_expect_success 'git diff-files' '
+       git diff-files --exit-code
+       test $? = 0
+'
+test_expect_success 'git diff-index --cached HEAD' '
+       git diff-index --exit-code --cached HEAD
+       test $? = 0
+'
+test_expect_success 'git diff-index --cached HEAD^' '
+       git diff-index --exit-code --cached HEAD^
+       test $? = 1
+'
+test_expect_success 'git diff-index --cached HEAD^' '
+       echo text >>b &&
+       echo 3 >c &&
+       git add . && {
+               git diff-index --exit-code --cached HEAD^
+               test $? = 1
+       }
+'
+test_expect_success 'git diff-tree -Stext HEAD^ HEAD -- b' '
+       git commit -m "text in b" && {
+               git diff-tree -p --exit-code -Stext HEAD^ HEAD -- b
+               test $? = 1
+       }
+'
+test_expect_success 'git diff-tree -Snot-found HEAD^ HEAD -- b' '
+       git diff-tree -p --exit-code -Snot-found HEAD^ HEAD -- b
+       test $? = 0
+'
+test_expect_success 'git diff-files' '
+       echo 3 >>c && {
+               git diff-files --exit-code
+               test $? = 1
+       }
+'
+test_expect_success 'git diff-index --cached HEAD' '
+       git update-index c && {
+               git diff-index --exit-code --cached HEAD
+               test $? = 1
+       }
+'
+
+test_done