feat: Ignore frozen files check by using a PR label

.circleci/config.yml

@@ -684,7 +684,21 @@ jobs:
             # If the target branch is not develop, do not run this check
             if [ "$TARGET_BRANCH" != "develop" ]; then
               echo "Target branch is not develop, skipping frozen files check"
-              exit 0
+              circleci-agent step halt
+            fi
+      - run:
+          name: Check if PR has exempt label
+          command: |
+            # Get PR number from CIRCLE_PULL_REQUEST
+            PR_NUMBER=$(echo $CIRCLE_PULL_REQUEST | rev | cut -d/ -f1 | rev)
+
+            # Use GitHub API to get labels
+            LABELS=$(curl -s "https://api.github.com/repos/${CIRCLE_PROJECT_USERNAME}/${CIRCLE_PROJECT_REPONAME}/pulls/${PR_NUMBER}" | jq -r .labels)
+
+            # If the PR has the "S-exempt-frozen-files" label, do not run this check
+            if echo $LABELS | jq -e 'any(.[]; .name == "S-exempt-frozen-files")' > /dev/null; then
+              echo "Skipping frozen files check, PR has exempt label"
+              circleci-agent step halt
             fi
       - run:
           name: Check frozen files

packages/contracts-bedrock/meta/CODE_FREEZES.md

@@ -0,0 +1,22 @@
+# Smart Contract Code Freeze Process
+
+The Smart Contract Freeze Process is used to protect specific files from accidental changes during sensitive periods.
+
+## Code Freeze
+
+Code freezes are implemented by comparison of the bytecode and source code hashes of the local file against the upstream files.
+
+To enable a code freeze, follow these steps:
+
+1. Create a PR.
+2. The `semver-lock.json` file should already be up to date, but run anyway `just semver-lock` to be sure.
+3. Comment out the path and filename of the file/s you want to freeze in check-frozen-files.sh.
+
+To disable a code freeze, comment out the path and filename of the file/s you want to unfreeze in check-frozen-files.sh.
+1. Create a PR.
+2. Uncomment the path and filename of all files in check-frozen-files.sh.
+
+## Exceptions
+
+To bypass the freeze you can apply the "S-exempt-frozen-files" label on affected PRs. This should be done upon agreement with the code owner. Expected uses of this exception are to fix issues found on audits or to add comments to frozen files.
+

packages/contracts-bedrock/meta/POLICY.md

@@ -23,6 +23,10 @@ For any policies on contributing, please see [CONTRIBUTING](./CONTRIBUTING.md)
 
 For our versioning policy, please see our policy on [VERSIONING](./VERSIONING.md)
 
+## Code Freeze Policy
+
+For our code freeze policy, please see our doc on [CODE FREEZES](./CODE_FREEZES.md)
+
 ## Upgrade Policy
 
 For the solidity upgrade policy, please see our doc on [SOLIDITY UPGRADES](./SOLIDITY_UPGRADES.md)