Add pre-commit autoupdate check

- Added a check in tox that warns if the pre-commit
hook versions need updating.
- Added this check as a pre-commit hook.
- Removed `pre-commit autoupdate` from the Makefile
since it's redundant

.pre-commit-config.yaml

@@ -40,3 +40,10 @@ repos:
       files: ''
       pass_filenames: false
       verbose: true
+    - id: tox-precommit
+      name: run pre-commit version check from tox
+      description: Checks if `pre-commit autoupdate` is up-to-date
+      entry: tox -e precommit
+      language: system
+      pass_filenames: false
+      verbose: true

Makefile

@@ -15,7 +15,6 @@ requirements:
 
 precommit:
 	pre-commit install
-	pre-commit autoupdate
 	pre-commit run --all-files --show-diff-on-failure
 
 coverage:

README.rst

@@ -93,8 +93,8 @@ To automatically run checks before you commit your changes you should run:
 
     $ make precommit
 
-This will install the git hook scripts for the first time, it will update to the
-latest versions of the hooks and run the pre-commit tool.
+This will install the git hook scripts for the first time and run the
+``pre-commit`` tool.
 Now ``pre-commit`` will run automatically on ``git commit``.
 
 

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py310,py311,requirements,lint,test,test-docs
+envlist = py310,py311,requirements,precommit,lint,test,test-docs
 
 [testenv]
 setenv =
@@ -66,7 +66,22 @@ commands =
     bash -c 'diff -w requirements.txt <(pipenv requirements)'
     bash -c 'diff -w requirements-dev.txt <(pipenv requirements --dev)'
 
+[testenv:precommit]
+description="Check if `pre-commit autoupdate` is up-to-date."
+deps = pre-commit
+skipsdist=false
+allowlist_externals =
+    bash
+commands =
+    pre-commit --version
+    bash -c 'cp .pre-commit-config.yaml tmp-tox-precommit.yaml'
+    bash -c 'pre-commit autoupdate'
+    bash -c 'if ! diff -w .pre-commit-config.yaml tmp-tox-precommit.yaml; \
+            then echo "⚠️ [WARNING] pre-commit hooks are outdated"; fi'
+    bash -c 'cp tmp-tox-precommit.yaml .pre-commit-config.yaml'
+    bash -c 'rm tmp-tox-precommit.yaml'
+
 [gh-actions]
 python =
-    3.10: py310,pep8,lint,requirements,test,test-docs
-    3.11: py311,pep8,lint,requirements,test,test-docs
+    3.10: py310,pep8,lint,requirements,precommit,test,test-docs
+    3.11: py311,pep8,lint,requirements,precommit,test,test-docs