Exclude multiple files in pre-commit-hooks

Update, October 2026: I'm keeping this article as I wrote it in 2023. Some things have changed since then, so read Before You Try This Today before you copy the commands.

How do you list all the files to avoid during pre-commit-hooks?

The issue

I have 2 configuration files in 2 different dockerized app.

I am using pre-commit-hooks to check, among other things, the Yaml files in my project.

The 2 files I try to exclude are: notes-app/mkdocs.yml and blog-app/mkdocs.yml.

So I tried to list them in the config file, .pre-commit-config.yaml:

repos:
  - repo: https://github.com/pre-commit/pre-commit-hooks
    rev: v5.0.0
    hooks:
    - id: check-yaml
      exclude:
        - notes-app/mkdocs.yml
        - blog-app/mkdocs.yml

which of course did not work:

❯ git commit -m "blog-post: about pre-commit-hooks multiple exclusions"
An error has occurred: InvalidConfigError:
==> File .pre-commit-config.yaml
==> At Config()
==> At key: repos
==> At Repository(repo='https://github.com/pre-commit/pre-commit-hooks')
==> At key: hooks
==> At Hook(id='check-yaml')
==> At key: exclude
=====> Expected string got list
Check the log at /Users/cruder/.cache/pre-commit/pre-commit.log

Solution

repos:
  - repo: https://github.com/pre-commit/pre-commit-hooks
    rev: v5.0.0
    hooks:
      - id: check-yaml
        exclude: ^(notes-app/mkdocs\.yml|blog-app/mkdocs\.yml)$

The exclude key should be a single string, not a list.

In order to resolve the issue and still keep it on one line I had to create a conditional in...REGEX.

Before You Try This Today

Added on 2026-10-20. The article above is unchanged since 2023-10-09; these are the gotchas you may hit if you follow it today.

• These blocks are YAML, not shell. Tag them ```yaml if you copy them into your own docs, so they get the right highlighting.

• For a long list, use pre-commit's verbose regex. The docs suggest a YAML multi-line string with the (?x) flag, one path per line:

  - id: check-yaml
    exclude: |
      (?x)^(
          notes-app/mkdocs\.yml|
          blog-app/mkdocs\.yml
      )$
  

• exclude is matched with re.search. Without the ^...$ anchors, a pattern also matches inside longer paths: mkdocs\.yml alone would exclude old-mkdocs.yml too. Keep the anchors and escape the dots.

• You may not need to exclude these files at all. The usual reason check-yaml rejects mkdocs.yml is the !!python/name: tags that Material for MkDocs uses. args: [--unsafe] on the hook checks syntax only and accepts custom tags, so the files are still checked.

• exclude is a pre-commit setting, not a pre-commit-hooks one. It works the same way on any hook from any repo, and there's also a top-level exclude for the whole config.

• Pin rev to a current release with pre-commit autoupdate, rather than copying the version shown here.

References

• pre-commit: Regular expressions: files/exclude are Python regexes matched with re.search, and the (?x) multi-line example.
• pre-commit-hooks: check-yaml: the --unsafe and --allow-multiple-documents options.

Links checked on 2026-10-20.