From 0e9f62dab9fcce57279751bba47718d3f8baf3c8 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Thu, 2 Mar 2017 03:23:01 -0500 Subject: 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 --- builtin/merge.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'builtin/merge.c') diff --git a/builtin/merge.c b/builtin/merge.c index b65eeaa87d..84375db714 100644 --- a/builtin/merge.c +++ b/builtin/merge.c @@ -434,7 +434,7 @@ static void merge_name(const char *remote, struct strbuf *msg) char *found_ref; int len, early; - strbuf_branchname(&bname, remote); + strbuf_branchname(&bname, remote, 0); remote = bname.buf; memset(branch_head, 0, sizeof(branch_head)); -- cgit v1.2.1