From: Kyle Zhao <kylezhao@xxxxxxxxxxx>
This patch will give our callers more flexibility to use `git merge-tree`,
such as:
git merge-tree --write-tree --merge-base=branch^ HEAD branch
It would cherry-pick the commit at the tip of the branch on top of the
current commit even if the repository is bare.
Signed-off-by: Kyle Zhao <kylezhao@xxxxxxxxxxx>
---
merge-tree: allow specifying a base commit when --write-tree is passed
Thanks for Elijah's work. I'm very excited that merge-ort is integrated
into the git merge-tree, which means that we can use merge-ort in bare
repositories to optimize merge performance.
In this patch, I introduce a new --merge-base=<commit> option to allow
callers to specify a merge-base for the merge. This may allow users to
implement git cherry-pick and git rebase in bare repositories with git
merge-tree cmd.
Changes since v1:
* Changed merge_incore_nonrecursive() to merge_incore_recursive() when
merge-base is specified.
* Fixed c style problem.
* Moved commit lookup/die logic out to the parsing logic in
cmd_merge_tree().
* use test_commit for test
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1397%2Fkeyu98%2Fkz%2Fmerge-tree-option-merge-base-v2
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1397/keyu98/kz/merge-tree-option-merge-base-v2
Pull-Request: https://github.com/gitgitgadget/git/pull/1397
Range-diff vs v1:
1: 965e544c849 ! 1: ab4e5d5ad08 merge-tree.c: add --merge-base=<commit> option
@@ Metadata
## Commit message ##
merge-tree.c: add --merge-base=<commit> option
- This option allows users to specify a merge-base commit for the merge.
+ This patch will give our callers more flexibility to use `git merge-tree`,
+ such as:
- It will give our callers more flexibility to use the `git merge-tree`.
- For example:
+ git merge-tree --write-tree --merge-base=branch^ HEAD branch
- git merge-tree --merge-base=<sha1>^1 source-branch <sha1>
-
- This allows us to implement `git cherry-pick` in bare repositories.
+ It would cherry-pick the commit at the tip of the branch on top of the
+ current commit even if the repository is bare.
Signed-off-by: Kyle Zhao <kylezhao@xxxxxxxxxxx>
@@ builtin/merge-tree.c: struct merge_tree_options {
int allow_unrelated_histories;
int show_messages;
int name_only;
-+ char* merge_base;
++ const struct commit *base_commit;
};
static int real_merge(struct merge_tree_options *o,
@@ builtin/merge-tree.c: static int real_merge(struct merge_tree_options *o,
- * merge_incore_recursive in merge-ort.h
- */
- merge_bases = get_merge_bases(parent1, parent2);
-+ if (o->merge_base) {
-+ struct commit *c = lookup_commit_reference_by_name(o->merge_base);
-+ if (!c)
-+ die(_("could not lookup commit %s"), o->merge_base);
-+ commit_list_insert(c, &merge_bases);
+- if (!merge_bases && !o->allow_unrelated_histories)
+- die(_("refusing to merge unrelated histories"));
+- merge_bases = reverse_commit_list(merge_bases);
++ if (o->base_commit) {
++ struct tree *base_tree, *parent1_tree, *parent2_tree;
++
++ opt.ancestor = "specified merge base";
++ base_tree = get_commit_tree(o->base_commit);
++ parent1_tree = get_commit_tree(parent1);
++ parent2_tree = get_commit_tree(parent2);
++ merge_incore_nonrecursive(&opt, base_tree, parent1_tree, parent2_tree, &result);
+ } else {
+ /*
+ * Get the merge bases, in reverse order; see comment above
+ * merge_incore_recursive in merge-ort.h
+ */
+ merge_bases = get_merge_bases(parent1, parent2);
++ if (!merge_bases && !o->allow_unrelated_histories)
++ die(_("refusing to merge unrelated histories"));
++ merge_bases = reverse_commit_list(merge_bases);
++ merge_incore_recursive(&opt, merge_bases, parent1, parent2, &result);
+ }
- if (!merge_bases && !o->allow_unrelated_histories)
- die(_("refusing to merge unrelated histories"));
- merge_bases = reverse_commit_list(merge_bases);
+
+- merge_incore_recursive(&opt, merge_bases, parent1, parent2, &result);
+ if (result.clean < 0)
+ die(_("failure to merge"));
+
+@@ builtin/merge-tree.c: static int real_merge(struct merge_tree_options *o,
+
+ int cmd_merge_tree(int argc, const char **argv, const char *prefix)
+ {
++ const char *merge_base = NULL;
+ struct merge_tree_options o = { .show_messages = -1 };
+ int expected_remaining_argc;
+ int original_argc;
@@ builtin/merge-tree.c: int cmd_merge_tree(int argc, const char **argv, const char *prefix)
&o.allow_unrelated_histories,
N_("allow merging unrelated histories"),
PARSE_OPT_NONEG),
+ OPT_STRING(0, "merge-base",
-+ &o.merge_base,
++ &merge_base,
+ N_("commit"),
-+ N_("specify a merge-base commit for the merge")),
++ N_("specify a merge-base for the merge")),
OPT_END()
};
+@@ builtin/merge-tree.c: int cmd_merge_tree(int argc, const char **argv, const char *prefix)
+ usage_with_options(merge_tree_usage, mt_options);
+
+ /* Do the relevant type of merge */
+- if (o.mode == MODE_REAL)
++ if (o.mode == MODE_REAL) {
++ if (merge_base) {
++ o.base_commit = lookup_commit_reference_by_name(merge_base);
++ if (!o.base_commit)
++ die(_("could not lookup commit %s"), merge_base);
++ }
+ return real_merge(&o, argv[0], argv[1], prefix);
++ }
+ else
+ return trivial_merge(argv[0], argv[1], argv[2]);
+ }
## t/t4301-merge-tree-write-tree.sh ##
@@ t/t4301-merge-tree-write-tree.sh: test_expect_success SANITY 'merge-ort fails gracefully in a read-only repository
test_must_fail git -C read-only merge-tree side1 side2
'
-+# specify merge-base as parent of branch2.
-+# git merge-tree --merge-base=A O B
-+# Commit O: foo, bar
-+# Commit A: modify foo after Commit O
-+# Commit B: modify bar after Commit A
-+# Expected: foo is unchanged, modify bar
-+
+test_expect_success 'specify merge-base as parent of branch2' '
+ # Setup
+ git init base-b2-p && (
+ cd base-b2-p &&
-+ echo foo >foo &&
-+ echo bar >bar &&
-+ git add foo bar &&
-+ git commit -m O &&
-+
-+ git branch O &&
-+ git branch A &&
-+
-+ git checkout A &&
-+ echo "A" >foo &&
-+ git add foo &&
-+ git commit -m A &&
-+
-+ git checkout -b B &&
-+ echo "B" >bar &&
-+ git add bar &&
-+ git commit -m B
++ test_commit c1 file1 &&
++ test_commit c2 file2 &&
++ test_commit c3 file3
+ ) &&
+ # Testing
+ (
+ cd base-b2-p &&
-+ TREE_OID=$(git merge-tree --merge-base=A O B) &&
++ TREE_OID=$(git merge-tree --write-tree --merge-base=c2 c1 c3) &&
+
+ q_to_tab <<-EOF >expect &&
-+ 100644 blob $(git rev-parse B:bar)Qbar
-+ 100644 blob $(git rev-parse O:foo)Qfoo
++ 100644 blob $(git rev-parse c1:file1)Qfile1
++ 100644 blob $(git rev-parse c3:file3)Qfile3
+ EOF
+
+ git ls-tree $TREE_OID >actual &&
Documentation/git-merge-tree.txt | 4 +++
builtin/merge-tree.c | 43 ++++++++++++++++++++++++--------
t/t4301-merge-tree-write-tree.sh | 23 +++++++++++++++++
3 files changed, 60 insertions(+), 10 deletions(-)
diff --git a/Documentation/git-merge-tree.txt b/Documentation/git-merge-tree.txt
index d6c356740ef..e762209b76d 100644
--- a/Documentation/git-merge-tree.txt
+++ b/Documentation/git-merge-tree.txt
@@ -64,6 +64,10 @@ OPTIONS
share no common history. This flag can be given to override that
check and make the merge proceed anyway.
+--merge-base=<commit>::
+ Instead of finding the merge-bases for <branch1> and <branch2>,
+ specify a merge-base for the merge.
+
[[OUTPUT]]
OUTPUT
------
diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c
index ae5782917b9..089ea8fac81 100644
--- a/builtin/merge-tree.c
+++ b/builtin/merge-tree.c
@@ -3,6 +3,7 @@
#include "tree-walk.h"
#include "xdiff-interface.h"
#include "help.h"
+#include "commit.h"
#include "commit-reach.h"
#include "merge-ort.h"
#include "object-store.h"
@@ -402,6 +403,7 @@ struct merge_tree_options {
int allow_unrelated_histories;
int show_messages;
int name_only;
+ const struct commit *base_commit;
};
static int real_merge(struct merge_tree_options *o,
@@ -430,16 +432,26 @@ static int real_merge(struct merge_tree_options *o,
opt.branch1 = branch1;
opt.branch2 = branch2;
- /*
- * Get the merge bases, in reverse order; see comment above
- * merge_incore_recursive in merge-ort.h
- */
- merge_bases = get_merge_bases(parent1, parent2);
- if (!merge_bases && !o->allow_unrelated_histories)
- die(_("refusing to merge unrelated histories"));
- merge_bases = reverse_commit_list(merge_bases);
+ if (o->base_commit) {
+ struct tree *base_tree, *parent1_tree, *parent2_tree;
+
+ opt.ancestor = "specified merge base";
+ base_tree = get_commit_tree(o->base_commit);
+ parent1_tree = get_commit_tree(parent1);
+ parent2_tree = get_commit_tree(parent2);
+ merge_incore_nonrecursive(&opt, base_tree, parent1_tree, parent2_tree, &result);
+ } else {
+ /*
+ * Get the merge bases, in reverse order; see comment above
+ * merge_incore_recursive in merge-ort.h
+ */
+ merge_bases = get_merge_bases(parent1, parent2);
+ if (!merge_bases && !o->allow_unrelated_histories)
+ die(_("refusing to merge unrelated histories"));
+ merge_bases = reverse_commit_list(merge_bases);
+ merge_incore_recursive(&opt, merge_bases, parent1, parent2, &result);
+ }
- merge_incore_recursive(&opt, merge_bases, parent1, parent2, &result);
if (result.clean < 0)
die(_("failure to merge"));
@@ -478,6 +490,7 @@ static int real_merge(struct merge_tree_options *o,
int cmd_merge_tree(int argc, const char **argv, const char *prefix)
{
+ const char *merge_base = NULL;
struct merge_tree_options o = { .show_messages = -1 };
int expected_remaining_argc;
int original_argc;
@@ -505,6 +518,10 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix)
&o.allow_unrelated_histories,
N_("allow merging unrelated histories"),
PARSE_OPT_NONEG),
+ OPT_STRING(0, "merge-base",
+ &merge_base,
+ N_("commit"),
+ N_("specify a merge-base for the merge")),
OPT_END()
};
@@ -544,8 +561,14 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix)
usage_with_options(merge_tree_usage, mt_options);
/* Do the relevant type of merge */
- if (o.mode == MODE_REAL)
+ if (o.mode == MODE_REAL) {
+ if (merge_base) {
+ o.base_commit = lookup_commit_reference_by_name(merge_base);
+ if (!o.base_commit)
+ die(_("could not lookup commit %s"), merge_base);
+ }
return real_merge(&o, argv[0], argv[1], prefix);
+ }
else
return trivial_merge(argv[0], argv[1], argv[2]);
}
diff --git a/t/t4301-merge-tree-write-tree.sh b/t/t4301-merge-tree-write-tree.sh
index 013b77144bd..64bfe6f4a41 100755
--- a/t/t4301-merge-tree-write-tree.sh
+++ b/t/t4301-merge-tree-write-tree.sh
@@ -819,4 +819,27 @@ test_expect_success SANITY 'merge-ort fails gracefully in a read-only repository
test_must_fail git -C read-only merge-tree side1 side2
'
+test_expect_success 'specify merge-base as parent of branch2' '
+ # Setup
+ git init base-b2-p && (
+ cd base-b2-p &&
+ test_commit c1 file1 &&
+ test_commit c2 file2 &&
+ test_commit c3 file3
+ ) &&
+ # Testing
+ (
+ cd base-b2-p &&
+ TREE_OID=$(git merge-tree --write-tree --merge-base=c2 c1 c3) &&
+
+ q_to_tab <<-EOF >expect &&
+ 100644 blob $(git rev-parse c1:file1)Qfile1
+ 100644 blob $(git rev-parse c3:file3)Qfile3
+ EOF
+
+ git ls-tree $TREE_OID >actual &&
+ test_cmp expect actual
+ )
+'
+
test_done
base-commit: 5af5e54106e20f65c913550c80aec3186b859e9b
--
gitgitgadget
