Re: [PATCH/RFC v4 4/5] checkout: implement "-" abbreviation, add docs and tests
From: Junio C Hamano <hidden>
Date: 2016-06-15 22:45:58
Thomas Rast [off-list ref] writes:
quoted hunk
@@ -133,6 +133,10 @@ the conflicted merge in the specified paths. + When this parameter names a non-branch (but still a valid commit object), your HEAD becomes 'detached'. ++ +As a special case, the "`@\{-N\}`" syntax for the N-th last branch +checks out the branch (instead of detaching). You may also specify +"`-`" which is synonymous with "`@\{-1\}`".
I mildly disagree with this wording. The new syntax is supposed to be a new way to name a branch, not a random non-branch committish that is special cased by "git checkout". I would further suggest that we should teach "git rev-parse --symbolic-full-name" and "git rev-parse --symbolic" about the new syntax, so that scripts can use the syntax to find out the same information. The "-" thing deserves a mention here in the documentation. That _is_ a special case that only applies to the "git checkout" command.
quoted hunk
diff --git a/builtin-checkout.c b/builtin-checkout.c index dc1de06..b0a101b 100644 --- a/builtin-checkout.c +++ b/builtin-checkout.c@@ -679,6 +679,9 @@ int cmd_checkout(int argc, const char **argv, const char *prefix) arg = argv[0]; has_dash_dash = (argc > 1) && !strcmp(argv[1], "--"); + if (!strcmp(arg, "-")) + arg = "@{-1}"; +
This is not quite nice as it could be, but it probably is Ok. If the
interpretation of @{-1} errors out, the user won't see an error message
that talks about "-" but instead the user will see "@{-1}".
Also it will look somewhat inconsistent to the end user who does not know
the internals for "-" claim to be a synonym for @{-1} but it really isn't.
For example, "git checkout -^0" does not work as "git checkout @{-1}^0".
To avoid such confusion, we could instead make "git checkout - <ENTER>" a
synonym for "git checkout @{-1} <ENTER>", without claiming to make "-" a
synonym for "@{-1}". In other words, "git checkout -" can become a very
narrow, focused special case that does not allow anything else, such as
pathspecs, "--" separator, nor --force and other options.