Accept tags in HEAD or MERGE_HEAD
HEAD and MERGE_HEAD (among other branch tips) should never hold a tag. That can only be caused by broken tools and is cumbersome to fix by an end user with: $ git update-ref HEAD $(git rev-parse HEAD^{commit}) which may look like a magic to a new person. Be easy, warn users (so broken tools can be fixed if they bother to report) and move on. Be robust, if the given SHA-1 cannot be resolved to a commit object, die (therefore return value is always valid). Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Nguyễn Thái Ngọc Duy committed
Sep 17, 2011 at 21:57 UTC
baf18fc261ca475343fe3cb9cd2c0dded4bc1bb7
7 files changed
+34
-14
builtin/commit.c
+4
-2
@@ -1396,7 +1396,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
1396
if (get_sha1("HEAD", sha1))
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current_head = NULL;
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else {
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- current_head = lookup_commit(sha1);
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+ current_head = lookup_commit_or_die(sha1, "HEAD");
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if (!current_head || parse_commit(current_head))
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die(_("could not parse HEAD commit"));
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}
@@ -1431,6 +1431,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
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pptr = &commit_list_insert(c->item, pptr)->next;
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} else if (whence == FROM_MERGE) {
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struct strbuf m = STRBUF_INIT;
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+ struct commit *commit;
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FILE *fp;
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if (!reflog_msg)
@@ -1444,7 +1445,8 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
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unsigned char sha1[20];
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if (get_sha1_hex(m.buf, sha1) < 0)
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die(_("Corrupt MERGE_HEAD file (%s)"), m.buf);
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- pptr = &commit_list_insert(lookup_commit(sha1), pptr)->next;
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+ commit = lookup_commit_or_die(sha1, "MERGE_HEAD");
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+ pptr = &commit_list_insert(commit, pptr)->next;
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}
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fclose(fp);
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strbuf_release(&m);
builtin/fmt-merge-msg.c
+1
-1
@@ -293,7 +293,7 @@ static int do_fmt_merge_msg(int merge_title, struct strbuf *in,
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struct commit *head;
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struct rev_info rev;
295
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- head = lookup_commit(head_sha1);
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+ head = lookup_commit_or_die(head_sha1, "HEAD");
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init_revisions(&rev, NULL);
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rev.commit_format = CMIT_FMT_ONELINE;
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rev.ignore_merges = 1;
builtin/merge.c
+2
-5
@@ -1036,11 +1036,8 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
1036
branch += 11;
1037
if (!branch || is_null_sha1(head_sha1))
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head_commit = NULL;
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- else {
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- head_commit = lookup_commit(head_sha1);
1041
- if (!head_commit)
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- die(_("could not parse HEAD"));
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- }
1039
+ else
1040
+ head_commit = lookup_commit_or_die(head_sha1, "HEAD");
1041
1042
git_config(git_merge_config, NULL);
1043
commit.c
+12
@@ -39,6 +39,18 @@ struct commit *lookup_commit_reference(const unsigned char *sha1)
39
return lookup_commit_reference_gently(sha1, 0);
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}
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+struct commit *lookup_commit_or_die(const unsigned char *sha1, const char *ref_name)
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+{
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+ struct commit *c = lookup_commit_reference(sha1);
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+ if (!c)
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+ die(_("could not parse %s"), ref_name);
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+ if (hashcmp(sha1, c->object.sha1)) {
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+ warning(_("%s %s is not a commit!"),
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+ ref_name, sha1_to_hex(sha1));
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+ }
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+ return c;
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+}
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+
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struct commit *lookup_commit(const unsigned char *sha1)
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{
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struct object *obj = lookup_object(sha1);
commit.h
+7
@@ -38,6 +38,13 @@ struct commit *lookup_commit_reference_gently(const unsigned char *sha1,
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int quiet);
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struct commit *lookup_commit_reference_by_name(const char *name);
40
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+/*
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+ * Look up object named by "sha1", dereference tag as necessary,
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+ * get a commit and return it. If "sha1" does not dereference to
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+ * a commit, use ref_name to report an error and die.
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+ */
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+struct commit *lookup_commit_or_die(const unsigned char *sha1, const char *ref_name);
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+
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int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size);
49
int parse_commit(struct commit *item);
50
http-push.c
+4
-4
@@ -1606,10 +1606,10 @@ static void fetch_symref(const char *path, char **symref, unsigned char *sha1)
1606
strbuf_release(&buffer);
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}
1608
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-static int verify_merge_base(unsigned char *head_sha1, unsigned char *branch_sha1)
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+static int verify_merge_base(unsigned char *head_sha1, struct ref *remote)
1610
{
1611
- struct commit *head = lookup_commit(head_sha1);
1612
- struct commit *branch = lookup_commit(branch_sha1);
1611
+ struct commit *head = lookup_commit_or_die(head_sha1, "HEAD");
1612
+ struct commit *branch = lookup_commit_or_die(remote->old_sha1, remote->name);
1613
struct commit_list *merge_bases = get_merge_bases(head, branch, 1);
1614
1615
return (merge_bases && !merge_bases->next && merge_bases->item == branch);
@@ -1680,7 +1680,7 @@ static int delete_remote_branch(const char *pattern, int force)
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return error("Remote branch %s resolves to object %s\nwhich does not exist locally, perhaps you need to fetch?", remote_ref->name, sha1_to_hex(remote_ref->old_sha1));
1681
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/* Remote branch must be an ancestor of remote HEAD */
1683
- if (!verify_merge_base(head_sha1, remote_ref->old_sha1)) {
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+ if (!verify_merge_base(head_sha1, remote_ref)) {
1684
return error("The branch '%s' is not an ancestor "
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"of your current HEAD.\n"
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"If you are sure you want to delete it,"
revision.c
+4
-2
@@ -986,10 +986,12 @@ static void prepare_show_merge(struct rev_info *revs)
986
const char **prune = NULL;
987
int i, prune_num = 1; /* counting terminating NULL */
988
989
- if (get_sha1("HEAD", sha1) || !(head = lookup_commit(sha1)))
989
+ if (get_sha1("HEAD", sha1))
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die("--merge without HEAD?");
991
- if (get_sha1("MERGE_HEAD", sha1) || !(other = lookup_commit(sha1)))
991
+ head = lookup_commit_or_die(sha1, "HEAD");
992
+ if (get_sha1("MERGE_HEAD", sha1))
993
die("--merge without MERGE_HEAD?");
994
+ other = lookup_commit_or_die(sha1, "MERGE_HEAD");
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add_pending_object(revs, &head->object, "HEAD");
996
add_pending_object(revs, &other->object, "MERGE_HEAD");
997
bases = get_merge_bases(head, other, 1);