From: Junio C Hamano <gitster@xxxxxxxxx>
"git check-ref-format --branch $name" feature was originally
introduced (and was advertised) as a way for scripts to take any
end-user supplied string (like "master", "@{-1}" etc.) and see if it
is usable when Git expects to see a branch name, and also obtain the
concrete branch name that the at-mark magic expands to.
Emphasize that "see if it is usable" role in the description and
clarify that the @{...} expansion only occurs when run from within a
repository.
[jn: split out from a larger patch]
Helped-by: Jeff King <peff@xxxxxxxx>
Signed-off-by: Junio C Hamano <gitster@xxxxxxxxx>
---
Documentation/git-check-ref-format.txt | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/Documentation/git-check-ref-format.txt b/Documentation/git-check-ref-format.txt
index 92777cef25..cf0a0b7df2 100644
--- a/Documentation/git-check-ref-format.txt
+++ b/Documentation/git-check-ref-format.txt
@@ -77,7 +77,14 @@ reference name expressions (see linkgit:gitrevisions[7]):
. at-open-brace `@{` is used as a notation to access a reflog entry.
-With the `--branch` option, it expands the ``previous branch syntax''
+With the `--branch` option, the command takes a name and checks if
+it can be used as a valid branch name (e.g. when creating a new
+branch). The rule `git check-ref-format --branch $name` implements
+may be stricter than what `git check-ref-format refs/heads/$name`
+says (e.g. a dash may appear at the beginning of a ref component,
+but it is explicitly forbidden at the beginning of a branch name).
+When run with `--branch` option in a repository, the input is first
+expanded for the ``previous branch syntax''
`@{-n}`. For example, `@{-1}` is a way to refer the last branch you
were on. This option should be used by porcelains to accept this
syntax anywhere a branch name is expected, so they can act as if you
--
2.15.0.rc1.287.g2b38de12cc
