From 83d9d66fbfee58b1543241047277f07b5b05a662 Mon Sep 17 00:00:00 2001
From: Greg Chadwick <gac@lowrisc.org>
Date: Fri, 12 May 2023 16:18:52 +0100
Subject: [PATCH] [util] Add script to check functioning of BLOCKFILE

The new script outputs warnings if any pattern in the BLOCKFILE doesn't
match a file in the repository tree along with a full list of files in
the repository tree that are blocked.

Signed-off-by: Greg Chadwick <gac@lowrisc.org>
---
 ci/scripts/check-pr-changes-allowed.py | 38 ++++++++++++++++++++++++--
 util/check-blockfile.sh                | 17 ++++++++++++
 2 files changed, 52 insertions(+), 3 deletions(-)
 create mode 100755 util/check-blockfile.sh

diff --git a/ci/scripts/check-pr-changes-allowed.py b/ci/scripts/check-pr-changes-allowed.py
index 852ad2689c443..56ef465f76475 100755
--- a/ci/scripts/check-pr-changes-allowed.py
+++ b/ci/scripts/check-pr-changes-allowed.py
@@ -157,6 +157,17 @@ def main() -> int:
         help='Name of the repository on github to read PR comments from',
         default='lowrisc/opentitan')
 
+    arg_parser.add_argument(
+        '--plain-block-msg',
+        help='''Just outputs the path of each blocked file with no further
+                information''',
+        action='store_true')
+
+    arg_parser.add_argument(
+        '--report-unused-patterns',
+        help='Produces a list of block patterns that did not block anything',
+        action='store_true')
+
     args = arg_parser.parse_args()
 
     blocklist = load_blockfile(args.block_file)
@@ -184,16 +195,37 @@ def main() -> int:
                 authorizers = ', '.join(
                     [f'{committers[handle]} ({handle})' for handle in
                         authorized_changes[change]])
-                print(f'{change} change is authorized by {authorizers}')
+
+                if not args.plain_block_msg:
+                    print(f'{change} change is authorized by {authorizers}')
+
+    if args.report_unused_patterns:
+        unused_patterns = set(blocklist)
+
+        used_patterns = set(sum(blocked_changes.values(), []))
+        unused_patterns = set(blocklist) - used_patterns
+
+        if unused_patterns:
+            print('WARNING: Unused patterns have been found:')
+
+            for pattern in unused_patterns:
+                print(pattern)
+
+            print('')
 
     if blocked_changes:
         # If there are blocked changes present print out what's been blocked and
         # the pattern(s) that blocked it and return error code 1
         for change, block_patterns in blocked_changes.items():
             patterns_str = ' '.join(block_patterns)
-            print(f'{change} blocked by pattern(s): {patterns_str}')
+            if args.plain_block_msg:
+                print(change)
+            else:
+                print(f'{change} blocked by pattern(s): {patterns_str}')
+
+        if not args.plain_block_msg:
+            print('UNAUTHORIZED CHANGES PRESENT, PR cannot be merged!')
 
-        print('UNAUTHORIZED CHANGES PRESENT, PR cannot be merged!')
         return 1
 
     print('No unauthorized changes, clear to merge')
diff --git a/util/check-blockfile.sh b/util/check-blockfile.sh
new file mode 100755
index 0000000000000..c30b018ba151a
--- /dev/null
+++ b/util/check-blockfile.sh
@@ -0,0 +1,17 @@
+#!/bin/sh
+# Copyright lowRISC contributors.
+# Licensed under the Apache License, Version 2.0, see LICENSE for details.
+# SPDX-License-Identifier: Apache-2.0
+
+echo "Checking BLOCKFILE. This will output all files blocked from changes and "
+echo "a warning if there are any patterns in BLOCKFILES which don't match any "
+echo "file. Must be run from repository root."
+
+# Produce a list of all files, chop off the first two characters which as './'
+# as the change blocker script doesn't work correctly with them.
+find -type f | cut -c 3- > ot-filelist
+
+./ci/scripts/check-pr-changes-allowed.py \
+  --plain-block-msg \
+  --report-unused-patterns \
+  ot-filelist