path: root/builtin/checkout.c
diff options
authorJeff King <>2017-03-02 08:23:01 (GMT)
committerJunio C Hamano <>2017-03-02 19:05:04 (GMT)
commit0e9f62dab9fcce57279751bba47718d3f8baf3c8 (patch)
treef608d9f021ea84e09b0f24c3682891deacee33b0 /builtin/checkout.c
parent0705fe202dd30009e2033e96a17cb12299bf5ab3 (diff)
interpret_branch_name: allow callers to restrict expansions
The interpret_branch_name() function converts names like @{-1} and @{upstream} into branch names. The expanded ref names are not fully qualified, and may be outside of the refs/heads/ namespace (e.g., "@" expands to "HEAD", and "@{upstream}" is likely to be in "refs/remotes/"). This is OK for callers like dwim_ref() which are primarily interested in resolving the resulting name, no matter where it is. But callers like "git branch" treat the result as a branch name in refs/heads/. When we expand to a ref outside that namespace, the results are very confusing (e.g., "git branch @" tries to create refs/heads/HEAD, which is nonsense). Callers can't know from the returned string how the expansion happened (e.g., did the user really ask for a branch named "HEAD", or did we do a bogus expansion?). One fix would be to return some out-parameters describing the types of expansion that occurred. This has the benefit that the caller can generate precise error messages ("I understood @{upstream} to mean origin/master, but that is a remote tracking branch, so you cannot create it as a local name"). However, out-parameters make the function interface somewhat cumbersome. Instead, let's do the opposite: let the caller tell us which elements to expand. That's easier to pass in, and none of the callers give more precise error messages than "@{upstream} isn't a valid branch name" anyway (which should be sufficient). The strbuf_branchname() function needs a similar parameter, as most of the callers access interpret_branch_name() through it. We can break the callers down into two groups: 1. Callers that are happy with any kind of ref in the result. We pass "0" here, so they continue to work without restrictions. This includes merge_name(), the reflog handling in add_pending_object_with_path(), and substitute_branch_name(). This last is what powers dwim_ref(). 2. Callers that have funny corner cases (mostly in git-branch and git-checkout). These need to make use of the new parameter, but I've left them as "0" in this patch, and will address them individually in follow-on patches. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
Diffstat (limited to 'builtin/checkout.c')
1 files changed, 1 insertions, 1 deletions
diff --git a/builtin/checkout.c b/builtin/checkout.c
index 512492a..711a923 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -452,7 +452,7 @@ static void setup_branch_path(struct branch_info *branch)
struct strbuf buf = STRBUF_INIT;
- strbuf_branchname(&buf, branch->name);
+ strbuf_branchname(&buf, branch->name, 0);
if (strcmp(buf.buf, branch->name))
branch->name = xstrdup(buf.buf);
strbuf_splice(&buf, 0, 0, "refs/heads/", 11);