static void describe_detached_head(char *msg, struct commit *commit)
{
struct strbuf sb = STRBUF_INIT;
+ struct pretty_print_context ctx = {0};
parse_commit(commit);
- pretty_print_commit(CMIT_FMT_ONELINE, commit, &sb, 0, NULL, NULL, 0, 0);
+ pretty_print_commit(CMIT_FMT_ONELINE, commit, &sb, &ctx);
fprintf(stderr, "%s %s... %s\n", msg,
find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf);
strbuf_release(&sb);
topts.initial_checkout = is_cache_unborn();
topts.update = 1;
topts.merge = 1;
- topts.gently = opts->merge;
+ topts.gently = opts->merge && old->commit;
topts.verbose_update = !opts->quiet;
topts.fn = twoway_merge;
topts.dir = xcalloc(1, sizeof(*topts.dir));
topts.dir->flags |= DIR_SHOW_IGNORED;
topts.dir->exclude_per_dir = ".gitignore";
- tree = parse_tree_indirect(old->commit->object.sha1);
+ tree = parse_tree_indirect(old->commit ?
+ old->commit->object.sha1 :
+ (unsigned char *)EMPTY_TREE_SHA1_BIN);
init_tree_desc(&trees[0], tree->buffer, tree->size);
tree = parse_tree_indirect(new->commit->object.sha1);
init_tree_desc(&trees[1], tree->buffer, tree->size);
struct merge_options o;
if (!opts->merge)
return 1;
- parse_commit(old->commit);
+
+ /*
+ * Without old->commit, the below is the same as
+ * the two-tree unpack we already tried and failed.
+ */
+ if (!old->commit)
+ return 1;
/* Do more real merge */
parse_commit(new->commit);
}
- if (!old.commit && !opts->force) {
- if (!opts->quiet) {
- warning("You appear to be on a branch yet to be born.");
- warning("Forcing checkout of %s.", new->name);
- }
- opts->force = 1;
- }
-
ret = merge_working_tree(opts, &old, new);
if (ret)
return ret;
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)
{
struct tree *source_tree = NULL;
char *conflict_style = NULL;
int patch_mode = 0;
+ int dwim_new_local_branch = 1;
struct option options[] = {
OPT__QUIET(&opts.quiet),
OPT_STRING('b', NULL, &opts.new_branch, "new branch", "branch"),
2),
OPT_SET_INT('3', "theirs", &opts.writeout_stage, "stage",
3),
- OPT_BOOLEAN('f', NULL, &opts.force, "force"),
+ OPT_BOOLEAN('f', "force", &opts.force, "force"),
OPT_BOOLEAN('m', "merge", &opts.merge, "merge"),
OPT_STRING(0, "conflict", &conflict_style, "style",
"conflict style (merge or diff3)"),
OPT_BOOLEAN('p', "patch", &patch_mode, "select hunks interactively"),
+ { OPTION_BOOLEAN, 0, "guess", &dwim_new_local_branch, NULL,
+ "second guess 'git checkout no-such-branch'",
+ PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
OPT_END(),
};
int has_dash_dash;
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);
* 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).
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 &&
+ dwim_new_local_branch &&
+ 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 */
}
no_reference:
+
+ if (opts.track == BRANCH_TRACK_UNSPECIFIED)
+ opts.track = git_branch_track;
+
if (argc) {
const char **pathspec = get_pathspec(prefix, argv);