DWIM "git checkout frotz" to "git checkout -b frotz origin/frotz"

When 'frotz' is not a valid object name and not a tracked filename,
we used to complain and failed this command.  When there is only
one remote that has 'frotz' as one of its tracking branches, we can
DWIM it as a request to create a local branch 'frotz' forking from
the matching remote tracking branch.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Junio C Hamano 2009-10-18 00:13:47 -07:00
parent c6e8c8005a
commit 70c9ac2f19

View file

@ -572,6 +572,40 @@ static int interactive_checkout(const char *revision, const char **pathspec,
return run_add_interactive(revision, "--patch=checkout", pathspec);
}
struct tracking_name_data {
const char *name;
char *remote;
int unique;
};
static int check_tracking_name(const char *refname, const unsigned char *sha1,
int flags, void *cb_data)
{
struct tracking_name_data *cb = cb_data;
const char *slash;
if (prefixcmp(refname, "refs/remotes/"))
return 0;
slash = strchr(refname + 13, '/');
if (!slash || strcmp(slash + 1, cb->name))
return 0;
if (cb->remote) {
cb->unique = 0;
return 0;
}
cb->remote = xstrdup(refname);
return 0;
}
static const char *unique_tracking_name(const char *name)
{
struct tracking_name_data cb_data = { name, NULL, 1 };
for_each_ref(check_tracking_name, &cb_data);
if (cb_data.unique)
return cb_data.remote;
free(cb_data.remote);
return NULL;
}
int cmd_checkout(int argc, const char **argv, const char *prefix)
{
@ -630,8 +664,6 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
opts.new_branch = argv0 + 1;
}
if (opts.track == BRANCH_TRACK_UNSPECIFIED)
opts.track = git_branch_track;
if (conflict_style) {
opts.merge = 1; /* implied */
git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
@ -655,6 +687,11 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
* With no paths, if <something> is a commit, that is to
* switch to the branch or detach HEAD at it.
*
* With no paths, if <something> is _not_ a commit, no -t nor -b
* was given, and there is a tracking branch whose name is
* <something> in one and only one remote, then this is a short-hand
* to fork local <something> from that remote tracking branch.
*
* Otherwise <something> shall not be ambiguous.
* - If it's *only* a reference, treat it like case (1).
* - If it's only a path, treat it like case (2).
@ -677,7 +714,20 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
if (get_sha1(arg, rev)) {
if (has_dash_dash) /* case (1) */
die("invalid reference: %s", arg);
goto no_reference; /* case (3 -> 2) */
if (!patch_mode &&
opts.track == BRANCH_TRACK_UNSPECIFIED &&
!opts.new_branch &&
!check_filename(NULL, arg) &&
argc == 1) {
const char *remote = unique_tracking_name(arg);
if (!remote || get_sha1(remote, rev))
goto no_reference;
opts.new_branch = arg;
arg = remote;
/* DWIMmed to create local branch */
}
else
goto no_reference;
}
/* we can't end up being in (2) anymore, eat the argument */
@ -715,6 +765,10 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
}
no_reference:
if (opts.track == BRANCH_TRACK_UNSPECIFIED)
opts.track = git_branch_track;
if (argc) {
const char **pathspec = get_pathspec(prefix, argv);