The git check-ref-format command is used to check if a given reference name (refname) is acceptable according to Git’s naming conventions. It verifies whether the provided refname follows the rules and restrictions imposed by Git, and exits with a non-zero status if the refname is not considered valid.
In Git, a refname refers to a name that identifies a specific commit or branch within a repository. It can be a branch name, a tag name, or any other valid reference name. Refnames are used to uniquely identify and access specific points in the commit history of a repository.
When you run git check-ref-format, you provide a refname as an argument, and the command validates the refname based on the following rules:
- The refname must not contain any control characters (ASCII codes 0x00-0x1F and 0x7F).
- The refname must not start with the reserved prefix “refs/”.
- The refname must not start or end with a dot “.”.
- The refname must not contain two consecutive dots “..”.
- The refname must not end with a forward slash “/”.
If the provided refname violates any of these rules, the git check-ref-format command will exit with a non-zero status and print an error message describing the specific violation.
For example, if you want to check the validity of a refname called “my-branch”, you can run the following command:
# git check-ref-format --branch-name my-branch
If the refname is valid, the command will exit silently without any output. However, if the refname is invalid, the command will exit with a non-zero status, indicating the error, and display an error message describing the specific rule that was violated.
The git check-ref-format command is useful when you need to ensure that a refname you’re working with follows Git’s conventions. It can be used as a validation step in scripts or automation workflows to enforce naming rules and prevent errors related to invalid refnames.
It’s worth noting that the git check-ref-format command only checks the format of the refname and does not verify if the refname actually exists in the repository or points to a valid commit. For checking the existence or validity of references, you can use other Git commands such as git show-ref or git rev-parse.
For more information on Git refnames and the rules for valid refname formats, you can refer to the official Git documentation or specific resources on Git references and naming conventions.
git check-ref-format Command Examples
1. Check the format of the specified refname:
# git check-ref-format refs/head/refname
2. Print the name of the last branch checked out:
# git check-ref-format --branch @-1
3. Normalize a refname:
# git check-ref-format --normalize refs/head/refname