merge: teach --autostash option
In rebase, one can pass the `--autostash` option to cause the worktree to be automatically stashed before continuing with the rebase. This option is missing in merge, however. Implement the `--autostash` option and corresponding `merge.autoStash` option in merge which stashes before merging and then pops after. This option is useful when a developer has some local changes on a topic branch but they realize that their work depends on another branch. Previously, they had to run something like git fetch ... git stash push git merge FETCH_HEAD git stash pop but now, that is reduced to git fetch ... git merge --autostash FETCH_HEAD When an autostash is generated, it is automatically reapplied to the worktree only in three explicit situations: 1. An incomplete merge is commit using `git commit`. 2. A merge completes successfully. 3. A merge is aborted using `git merge --abort`. In all other situations where the merge state is removed using remove_merge_branch_state() such as aborting a merge via `git reset --hard`, the autostash is saved into the stash reflog instead keeping the worktree clean. Helped-by: Phillip Wood <phillip.wood@dunelm.org.uk> Suggested-by: Alban Gruin <alban.gruin@gmail.com> Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu committed
Apr 7, 2020 at 10:28 UTC
a03b55530ab844974b7058042a015fcfcd9e7a53
12 files changed
+214
-6
Documentation/config/merge.txt
+10
@@ -70,6 +70,16 @@ merge.stat::
70
Whether to print the diffstat between ORIG_HEAD and the merge result
71
at the end of the merge. True by default.
72
73
+merge.autoStash::
74
+ When set to true, automatically create a temporary stash entry
75
+ before the operation begins, and apply it after the operation
76
+ ends. This means that you can run merge on a dirty worktree.
77
+ However, use with care: the final stash application after a
78
+ successful merge might result in non-trivial conflicts.
79
+ This option can be overridden by the `--no-autostash` and
80
+ `--autostash` options of linkgit:git-merge[1].
81
+ Defaults to false.
82
+
83
merge.tool::
84
Controls which merge tool is used by linkgit:git-mergetool[1].
85
The list below shows the valid built-in values.
Documentation/git-merge.txt
+8
-3
@@ -94,7 +94,8 @@ will be appended to the specified message.
94
95
--abort::
96
Abort the current conflict resolution process, and
97
- try to reconstruct the pre-merge state.
97
+ try to reconstruct the pre-merge state. If an autostash entry is
98
+ present, apply it to the worktree.
99
+
100
If there were uncommitted worktree changes present when the merge
101
started, 'git merge --abort' will in some cases be unable to
@@ -102,11 +103,15 @@ reconstruct these changes. It is therefore recommended to always
103
commit or stash your changes before running 'git merge'.
104
+
105
'git merge --abort' is equivalent to 'git reset --merge' when
105
-`MERGE_HEAD` is present.
106
+`MERGE_HEAD` is present unless `MERGE_AUTOSTASH` is also present in
107
+which case 'git merge --abort' applies the stash entry to the worktree
108
+whereas 'git reset --merge' will save the stashed changes in the stash
109
+reflog.
110
111
--quit::
112
Forget about the current merge in progress. Leave the index
109
- and the working tree as-is.
113
+ and the working tree as-is. If `MERGE_AUTOSTASH` is present, the
114
+ stash entry will be saved to the stash reflog.
115
116
--continue::
117
After a 'git merge' stops due to conflicts you can conclude the
Documentation/merge-options.txt
+8
@@ -155,6 +155,14 @@ ifndef::git-pull[]
155
Note that not all merge strategies may support progress
156
reporting.
157
158
+--autostash::
159
+--no-autostash::
160
+ Automatically create a temporary stash entry before the operation
161
+ begins, and apply it after the operation ends. This means
162
+ that you can run the operation on a dirty worktree. However, use
163
+ with care: the final stash application after a successful
164
+ merge might result in non-trivial conflicts.
165
+
166
endif::git-pull[]
167
168
--allow-unrelated-histories::
branch.c
+1
@@ -344,6 +344,7 @@ void remove_merge_branch_state(struct repository *r)
344
unlink(git_path_merge_rr(r));
345
unlink(git_path_merge_msg(r));
346
unlink(git_path_merge_mode(r));
347
+ save_autostash(git_path_merge_autostash(r));
348
}
349
350
void remove_branch_state(struct repository *r, int verbose)
builtin/commit.c
+2
@@ -1713,6 +1713,8 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
1713
&oid, flags);
1714
}
1715
1716
+ apply_autostash(git_path_merge_autostash(the_repository));
1717
+
1718
UNLEAK(err);
1719
UNLEAK(sb);
1720
return 0;
builtin/merge.c
+25
@@ -82,6 +82,7 @@ static int show_progress = -1;
82
static int default_to_upstream = 1;
83
static int signoff;
84
static const char *sign_commit;
85
+static int autostash;
86
static int no_verify;
87
88
static struct strategy all_strategy[] = {
@@ -286,6 +287,7 @@ static struct option builtin_merge_options[] = {
287
OPT_SET_INT(0, "progress", &show_progress, N_("force progress reporting"), 1),
288
{ OPTION_STRING, 'S', "gpg-sign", &sign_commit, N_("key-id"),
289
N_("GPG sign commit"), PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
290
+ OPT_AUTOSTASH(&autostash),
291
OPT_BOOL(0, "overwrite-ignore", &overwrite_ignore, N_("update ignored files (default)")),
292
OPT_BOOL(0, "signoff", &signoff, N_("add Signed-off-by:")),
293
OPT_BOOL(0, "no-verify", &no_verify, N_("bypass pre-merge-commit and commit-msg hooks")),
@@ -475,6 +477,7 @@ static void finish(struct commit *head_commit,
477
/* Run a post-merge hook */
478
run_hook_le(NULL, "post-merge", squash ? "1" : "0", NULL);
479
480
+ apply_autostash(git_path_merge_autostash(the_repository));
481
strbuf_release(&reflog_message);
482
}
483
@@ -634,6 +637,9 @@ static int git_merge_config(const char *k, const char *v, void *cb)
637
return 0;
638
} else if (!strcmp(k, "gpg.mintrustlevel")) {
639
check_trust_level = 0;
640
+ } else if (!strcmp(k, "merge.autostash")) {
641
+ autostash = git_config_bool(k, v);
642
+ return 0;
643
}
644
645
status = fmt_merge_msg_config(k, v, cb);
@@ -1281,6 +1287,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
1287
if (abort_current_merge) {
1288
int nargc = 2;
1289
const char *nargv[] = {"reset", "--merge", NULL};
1290
+ struct strbuf stash_oid = STRBUF_INIT;
1291
1292
if (orig_argc != 2)
1293
usage_msg_opt(_("--abort expects no arguments"),
@@ -1289,8 +1296,17 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
1296
if (!file_exists(git_path_merge_head(the_repository)))
1297
die(_("There is no merge to abort (MERGE_HEAD missing)."));
1298
1299
+ if (read_oneliner(&stash_oid, git_path_merge_autostash(the_repository),
1300
+ READ_ONELINER_SKIP_IF_EMPTY))
1301
+ unlink(git_path_merge_autostash(the_repository));
1302
+
1303
/* Invoke 'git reset --merge' */
1304
ret = cmd_reset(nargc, nargv, prefix);
1305
+
1306
+ if (stash_oid.len)
1307
+ apply_autostash_oid(stash_oid.buf);
1308
+
1309
+ strbuf_release(&stash_oid);
1310
goto done;
1311
}
1312
@@ -1513,6 +1529,10 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
1529
goto done;
1530
}
1531
1532
+ if (autostash)
1533
+ create_autostash(the_repository,
1534
+ git_path_merge_autostash(the_repository),
1535
+ "merge");
1536
if (checkout_fast_forward(the_repository,
1537
&head_commit->object.oid,
1538
&commit->object.oid,
@@ -1579,6 +1599,11 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
1599
if (fast_forward == FF_ONLY)
1600
die(_("Not possible to fast-forward, aborting."));
1601
1602
+ if (autostash)
1603
+ create_autostash(the_repository,
1604
+ git_path_merge_autostash(the_repository),
1605
+ "merge");
1606
+
1607
/* We are going to make a new commit. */
1608
git_committer_info(IDENT_STRICT);
1609
builtin/rebase.c
+1
-2
@@ -1376,8 +1376,7 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
1376
{ OPTION_STRING, 'S', "gpg-sign", &gpg_sign, N_("key-id"),
1377
N_("GPG-sign commits"),
1378
PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
1379
- OPT_BOOL(0, "autostash", &options.autostash,
1380
- N_("automatically stash/stash pop before and after")),
1379
+ OPT_AUTOSTASH(&options.autostash),
1380
OPT_STRING_LIST('x', "exec", &exec, N_("exec"),
1381
N_("add exec lines after each commit of the "
1382
"editable list")),
parse-options.h
+1
@@ -336,5 +336,6 @@ int parse_opt_passthru_argv(const struct option *, const char *, int);
336
#define OPT_CLEANUP(v) OPT_STRING(0, "cleanup", v, N_("mode"), N_("how to strip spaces and #comments from message"))
337
#define OPT_PATHSPEC_FROM_FILE(v) OPT_FILENAME(0, "pathspec-from-file", v, N_("read pathspec from file"))
338
#define OPT_PATHSPEC_FILE_NUL(v) OPT_BOOL(0, "pathspec-file-nul", v, N_("with --pathspec-from-file, pathspec elements are separated with NUL character"))
339
+#define OPT_AUTOSTASH(v) OPT_BOOL(0, "autostash", v, N_("automatically stash/stash pop before and after"))
340
341
#endif
path.c
+1
@@ -1535,5 +1535,6 @@ REPO_GIT_PATH_FUNC(merge_msg, "MERGE_MSG")
1535
REPO_GIT_PATH_FUNC(merge_rr, "MERGE_RR")
1536
REPO_GIT_PATH_FUNC(merge_mode, "MERGE_MODE")
1537
REPO_GIT_PATH_FUNC(merge_head, "MERGE_HEAD")
1538
+REPO_GIT_PATH_FUNC(merge_autostash, "MERGE_AUTOSTASH")
1539
REPO_GIT_PATH_FUNC(fetch_head, "FETCH_HEAD")
1540
REPO_GIT_PATH_FUNC(shallow, "shallow")
path.h
+3
-1
@@ -177,11 +177,12 @@ struct path_cache {
177
const char *merge_rr;
178
const char *merge_mode;
179
const char *merge_head;
180
+ const char *merge_autostash;
181
const char *fetch_head;
182
const char *shallow;
183
};
184
184
-#define PATH_CACHE_INIT { NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL }
185
+#define PATH_CACHE_INIT { NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL }
186
187
const char *git_path_cherry_pick_head(struct repository *r);
188
const char *git_path_revert_head(struct repository *r);
@@ -190,6 +191,7 @@ const char *git_path_merge_msg(struct repository *r);
191
const char *git_path_merge_rr(struct repository *r);
192
const char *git_path_merge_mode(struct repository *r);
193
const char *git_path_merge_head(struct repository *r);
194
+const char *git_path_merge_autostash(struct repository *r);
195
const char *git_path_fetch_head(struct repository *r);
196
const char *git_path_shallow(struct repository *r);
197
t/t3033-merge-toplevel.sh
+22
@@ -142,6 +142,17 @@ test_expect_success 'refuse two-project merge by default' '
142
test_must_fail git merge five
143
'
144
145
+test_expect_success 'refuse two-project merge by default, quit before --autostash happens' '
146
+ t3033_reset &&
147
+ git reset --hard four &&
148
+ echo change >>one.t &&
149
+ git diff >expect &&
150
+ test_must_fail git merge --autostash five 2>err &&
151
+ test_i18ngrep ! "stash" err &&
152
+ git diff >actual &&
153
+ test_cmp expect actual
154
+'
155
+
156
test_expect_success 'two-project merge with --allow-unrelated-histories' '
157
t3033_reset &&
158
git reset --hard four &&
@@ -149,4 +160,15 @@ test_expect_success 'two-project merge with --allow-unrelated-histories' '
160
git diff --exit-code five
161
'
162
163
+test_expect_success 'two-project merge with --allow-unrelated-histories with --autostash' '
164
+ t3033_reset &&
165
+ git reset --hard four &&
166
+ echo change >>one.t &&
167
+ git diff one.t >expect &&
168
+ git merge --allow-unrelated-histories --autostash five 2>err &&
169
+ test_i18ngrep "Applied autostash." err &&
170
+ git diff one.t >actual &&
171
+ test_cmp expect actual
172
+'
173
+
174
test_done
t/t7600-merge.sh
+132
@@ -30,13 +30,17 @@ Testing basic merge operations/option parsing.
30
. "$TEST_DIRECTORY"/lib-gpg.sh
31
32
test_write_lines 1 2 3 4 5 6 7 8 9 >file
33
+cp file file.orig
34
test_write_lines '1 X' 2 3 4 5 6 7 8 9 >file.1
35
+test_write_lines 1 2 '3 X' 4 5 6 7 8 9 >file.3
36
test_write_lines 1 2 3 4 '5 X' 6 7 8 9 >file.5
37
test_write_lines 1 2 3 4 5 6 7 8 '9 X' >file.9
38
test_write_lines 1 2 3 4 5 6 7 8 '9 Y' >file.9y
39
test_write_lines '1 X' 2 3 4 5 6 7 8 9 >result.1
40
test_write_lines '1 X' 2 3 4 '5 X' 6 7 8 9 >result.1-5
41
+test_write_lines '1 X' 2 3 4 5 6 7 8 '9 X' >result.1-9
42
test_write_lines '1 X' 2 3 4 '5 X' 6 7 8 '9 X' >result.1-5-9
43
+test_write_lines '1 X' 2 '3 X' 4 '5 X' 6 7 8 '9 X' >result.1-3-5-9
44
test_write_lines 1 2 3 4 5 6 7 8 '9 Z' >result.9z
45
46
create_merge_msgs () {
@@ -675,6 +679,134 @@ test_expect_success 'refresh the index before merging' '
679
git merge c3
680
'
681
682
+test_expect_success 'merge with --autostash' '
683
+ git reset --hard c1 &&
684
+ git merge-file file file.orig file.9 &&
685
+ git merge --autostash c2 2>err &&
686
+ test_i18ngrep "Applied autostash." err &&
687
+ git show HEAD:file >merge-result &&
688
+ test_cmp result.1-5 merge-result &&
689
+ test_cmp result.1-5-9 file
690
+'
691
+
692
+test_expect_success 'merge with merge.autoStash' '
693
+ test_config merge.autoStash true &&
694
+ git reset --hard c1 &&
695
+ git merge-file file file.orig file.9 &&
696
+ git merge c2 2>err &&
697
+ test_i18ngrep "Applied autostash." err &&
698
+ git show HEAD:file >merge-result &&
699
+ test_cmp result.1-5 merge-result &&
700
+ test_cmp result.1-5-9 file
701
+'
702
+
703
+test_expect_success 'fast-forward merge with --autostash' '
704
+ git reset --hard c0 &&
705
+ git merge-file file file.orig file.5 &&
706
+ git merge --autostash c1 2>err &&
707
+ test_i18ngrep "Applied autostash." err &&
708
+ test_cmp result.1-5 file
709
+'
710
+
711
+test_expect_success 'octopus merge with --autostash' '
712
+ git reset --hard c1 &&
713
+ git merge-file file file.orig file.3 &&
714
+ git merge --autostash c2 c3 2>err &&
715
+ test_i18ngrep "Applied autostash." err &&
716
+ git show HEAD:file >merge-result &&
717
+ test_cmp result.1-5-9 merge-result &&
718
+ test_cmp result.1-3-5-9 file
719
+'
720
+
721
+test_expect_success 'conflicted merge with --autostash, --abort restores stash' '
722
+ git reset --hard c3 &&
723
+ cp file.1 file &&
724
+ test_must_fail git merge --autostash c7 &&
725
+ git merge --abort 2>err &&
726
+ test_i18ngrep "Applied autostash." err &&
727
+ test_cmp file.1 file
728
+'
729
+
730
+test_expect_success 'completed merge (git commit) with --no-commit and --autostash' '
731
+ git reset --hard c1 &&
732
+ git merge-file file file.orig file.9 &&
733
+ git diff >expect &&
734
+ git merge --no-commit --autostash c2 &&
735
+ git stash show -p MERGE_AUTOSTASH >actual &&
736
+ test_cmp expect actual &&
737
+ git commit 2>err &&
738
+ test_i18ngrep "Applied autostash." err &&
739
+ git show HEAD:file >merge-result &&
740
+ test_cmp result.1-5 merge-result &&
741
+ test_cmp result.1-5-9 file
742
+'
743
+
744
+test_expect_success 'completed merge (git merge --continue) with --no-commit and --autostash' '
745
+ git reset --hard c1 &&
746
+ git merge-file file file.orig file.9 &&
747
+ git diff >expect &&
748
+ git merge --no-commit --autostash c2 &&
749
+ git stash show -p MERGE_AUTOSTASH >actual &&
750
+ test_cmp expect actual &&
751
+ git merge --continue 2>err &&
752
+ test_i18ngrep "Applied autostash." err &&
753
+ git show HEAD:file >merge-result &&
754
+ test_cmp result.1-5 merge-result &&
755
+ test_cmp result.1-5-9 file
756
+'
757
+
758
+test_expect_success 'aborted merge (merge --abort) with --no-commit and --autostash' '
759
+ git reset --hard c1 &&
760
+ git merge-file file file.orig file.9 &&
761
+ git diff >expect &&
762
+ git merge --no-commit --autostash c2 &&
763
+ git stash show -p MERGE_AUTOSTASH >actual &&
764
+ test_cmp expect actual &&
765
+ git merge --abort 2>err &&
766
+ test_i18ngrep "Applied autostash." err &&
767
+ git diff >actual &&
768
+ test_cmp expect actual
769
+'
770
+
771
+test_expect_success 'aborted merge (reset --hard) with --no-commit and --autostash' '
772
+ git reset --hard c1 &&
773
+ git merge-file file file.orig file.9 &&
774
+ git diff >expect &&
775
+ git merge --no-commit --autostash c2 &&
776
+ git stash show -p MERGE_AUTOSTASH >actual &&
777
+ test_cmp expect actual &&
778
+ git reset --hard 2>err &&
779
+ test_i18ngrep "Autostash exists; creating a new stash entry." err &&
780
+ git diff --exit-code
781
+'
782
+
783
+test_expect_success 'quit merge with --no-commit and --autostash' '
784
+ git reset --hard c1 &&
785
+ git merge-file file file.orig file.9 &&
786
+ git diff >expect &&
787
+ git merge --no-commit --autostash c2 &&
788
+ git stash show -p MERGE_AUTOSTASH >actual &&
789
+ test_cmp expect actual &&
790
+ git diff HEAD >expect &&
791
+ git merge --quit 2>err &&
792
+ test_i18ngrep "Autostash exists; creating a new stash entry." err &&
793
+ git diff HEAD >actual &&
794
+ test_cmp expect actual
795
+'
796
+
797
+test_expect_success 'merge with conflicted --autostash changes' '
798
+ git reset --hard c1 &&
799
+ git merge-file file file.orig file.9y &&
800
+ git diff >expect &&
801
+ test_when_finished "test_might_fail git stash drop" &&
802
+ git merge --autostash c3 2>err &&
803
+ test_i18ngrep "Applying autostash resulted in conflicts." err &&
804
+ git show HEAD:file >merge-result &&
805
+ test_cmp result.1-9 merge-result &&
806
+ git stash show -p >actual &&
807
+ test_cmp expect actual
808
+'
809
+
810
cat >expected.branch <<\EOF
811
Merge branch 'c5-branch' (early part)
812
EOF