GIT-CHECK-REF-FORM(1)GIT-CHECK-REF-FORM(1)NAMEgit-check-ref-format - Ensures that a reference name is well formed
SYNOPSIS
git check-ref-format <refname>
git check-ref-format --print <refname>
git check-ref-format --branch <branchname-shorthand>
DESCRIPTION
Checks if a given refname is acceptable, and exits with a non-zero sta-
tus if it is not.
A reference is used in git to specify branches and tags. A branch head
is stored under the $GIT_DIR/refs/heads directory, and a tag is stored
under the $GIT_DIR/refs/tags directory (or, if refs are packed by git
gc, as entries in the $GIT_DIR/packed-refs file). git imposes the fol-
lowing rules on how references are named:
1. They can include slash / for hierarchical (directory) grouping, but
no slash-separated component can begin with a dot ..
2. They must contain at least one /. This enforces the presence of a
category like heads/, tags/ etc. but the actual names are not
restricted.
3. They cannot have two consecutive dots .. anywhere.
4. They cannot have ASCII control characters (i.e. bytes whose values
are lower than \040, or \177 DEL), space, tilde ~, caret {caret},
colon :, question-mark ?, asterisk *, or open bracket [ anywhere.
5. They cannot end with a slash / nor a dot ..
6. They cannot end with the sequence .lock.
7. They cannot contain a sequence @{.
8. They cannot contain a \.
These rules make it easy for shell script based tools to parse refer-
ence names, pathname expansion by the shell when a reference name is
used unquoted (by mistake), and also avoids ambiguities in certain ref-
erence name expressions (see gitrevisions(7)):
1. A double-dot .. is often used as in ref1..ref2, and in some contexts
this notation means {caret}ref1 ref2 (i.e. not in ref1 and in ref2).
2. A tilde ~ and caret {caret} are used to introduce the postfix nth
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GIT-CHECK-REF-FORM(1)GIT-CHECK-REF-FORM(1)
parent and peel onion operation.
3. A colon : is used as in srcref:dstref to mean "use srcref’s
value and store it in dstref" in fetch and push operations. It may
also be used to select a specific object such as with git cat-file:
"git cat-file blob v1.3.3:refs.c".
4. at-open-brace @{ is used as a notation to access a reflog entry.
With the --print option, if refname is acceptable, it prints the canon-
icalized name of a hypothetical reference with that name. That is, it
prints refname with any extra / characters removed.
With the --branch option, it expands the “previous branch syn-
tax” @{-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
typed the branch name.
EXAMPLES
o Print the name of the previous branch:
.ft C
$ git check-ref-format --branch @{-1}
.ft
o Determine the reference name to use for a new branch:
.ft C
$ ref=$(git check-ref-format --print "refs/heads/$newbranch") ||
die "we do not like '$newbranch' as a branch name."
.ft
GIT
Part of the git(1) suite
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