feat: auto-update pre-commit config

build_helpers/pre_commit_update.py

@@ -1,5 +1,7 @@
 # File used in CI to ensure pre-commit dependencies are kept up-to-date.
 
+import argparse
+import re
 import sys
 from pathlib import Path
 
@@ -10,6 +12,24 @@ pre_commit_file = Path(".pre-commit-config.yaml")
 require_dev = Path("requirements-dev.txt")
 require = Path("requirements.txt")
 
+
+parser = argparse.ArgumentParser()
+parser.add_argument("--update", action="store_true")
+args = parser.parse_args()
+
+
+def replace_dependency_version(pre_commit_text: str, dependency: str) -> tuple[str, bool]:
+    """
+    Regex-based replacement of a dependency version in the pre-commit config file.
+    using regex here ensures we only replace the version of the dependency while
+    keeping the overall file intact.
+    """
+    package_name = dependency.split("==", 1)[0]
+    pattern = re.compile(rf"^(\s*-\s+){re.escape(package_name)}==.*$", re.MULTILINE)
+    updated_text, replacements = pattern.subn(rf"\1{dependency}", pre_commit_text, count=1)
+    return updated_text, replacements > 0 and updated_text != pre_commit_text
+
+
 with require_dev.open("r") as rfile:
     requirements = rfile.readlines()
 
@@ -23,6 +43,18 @@ supported = ("types-", "SQLAlchemy", "scipy-stubs")
 # Only keep the first part of the line up to the first space
 type_reqs = [r.strip("\n").split()[0] for r in requirements if r.startswith(supported)]
 
+with pre_commit_file.open("r") as file:
+    pre_commit_text = file.read()
+
+updated = False
+for req in type_reqs:
+    pre_commit_text, req_updated = replace_dependency_version(pre_commit_text, req)
+    updated = updated or req_updated
+
+if args.update and updated:
+    with pre_commit_file.open("w") as file:
+        file.write(pre_commit_text)
+
 with pre_commit_file.open("r") as file:
     f = yaml.load(file, Loader=yaml.SafeLoader)
 
@@ -40,12 +72,20 @@ for hook in hooks:
 
 for req in type_reqs:
     if req not in hooks:
-        errors.append(f"{req} is missing in pre-config file.")
+        errors.append(f"{req} is missing in pre-commit config file.")
+
+if updated:
+    if args.update:
+        errors.append(".pre-commit-config.yaml was updated to match the requirements files.")
+    else:
+        errors.append(
+            ".pre-commit-config.yaml is outdated. Run build_helpers/pre_commit_update.py --update."
+        )
 
 
 if errors:
     for e in errors:
         print(e)
-    sys.exit(1)
+    sys.exit(1 if not (args.update and updated) else 0)
 
 sys.exit(0)