fix: align migrated review helpers with repository lint policy

.claude/skills/review-pr/scripts/verify_line_numbers.py

@@ -6,11 +6,24 @@
 import argparse
 import ast
 import json
-import re
 import subprocess
 import sys
 
-HUNK = re.compile(r"^@@ -(\d+)(?:,(\d+))? \+(\d+)(?:,(\d+))? @@")
+
+def parse_hunk(text):
+    """Parse a unified-diff hunk header without a runtime dependency."""
+    parts = text.split(" ", 4)
+    if len(parts) < 4 or parts[0] != "@@" or not parts[3].startswith("@@"):
+        return None
+    bounds = []
+    for value, sign in zip(parts[1:3], ("-", "+")):
+        if not value.startswith(sign):
+            return None
+        numbers = value[1:].split(",")
+        if len(numbers) not in (1, 2) or not all(number.isdecimal() for number in numbers):
+            return None
+        bounds.extend((numbers[0], numbers[1] if len(numbers) == 2 else None))
+    return tuple(bounds)
 
 
 def diff_path(value):
@@ -29,8 +42,8 @@ def diff_lines(diff):
         if text.startswith("diff --git "):
             old_path = new_path = None
             old_remaining = new_remaining = 0
-        elif match := HUNK.match(text):
-            old_line, old_count, new_line, new_count = match.groups()
+        elif hunk := parse_hunk(text):
+            old_line, old_count, new_line, new_count = hunk
             old_line, new_line = int(old_line), int(new_line)
             old_remaining = int(old_count) if old_count is not None else 1
             new_remaining = int(new_count) if new_count is not None else 1

.claude/skills/review-pr/tests/test_helpers.py

@@ -60,7 +60,6 @@ else:
             check=False,
         )
 
-
     def test_select_filters_drafts_wip_and_own_prs(self):
         prs = [
             {"number": i, "title": title, "author": {"login": author}, "isDraft": draft}
@@ -113,17 +112,17 @@ else:
                 self.assertNotEqual(result.returncode, 0)
 
     def test_verify_deleted_file_on_left(self):
-        diff = (
-            "diff --git a/gone.py b/gone.py\n--- a/gone.py\n+++ /dev/null\n"
-            "@@ -1 +0,0 @@\n-old\n"
-        )
-        result = self.verify(
-            [{"path": "gone.py", "line": 1, "side": "LEFT", "body": "Check"}], diff
-        )
+        diff = "diff --git a/gone.py b/gone.py\n--- a/gone.py\n+++ /dev/null\n@@ -1 +0,0 @@\n-old\n"
+        result = self.verify([{"path": "gone.py", "line": 1, "side": "LEFT", "body": "Check"}], diff)
         self.assertEqual(result.returncode, 0, result.stderr)
-        result = self.verify(
-            [{"path": "gone.py", "line": 1, "side": "RIGHT", "body": "Check"}], diff
-        )
+        result = self.verify([{"path": "gone.py", "line": 1, "side": "RIGHT", "body": "Check"}], diff)
+        self.assertNotEqual(result.returncode, 0)
+
+    def test_verify_new_file_with_explicit_zero_old_count(self):
+        diff = "diff --git a/new.py b/new.py\n--- /dev/null\n+++ b/new.py\n@@ -0,0 +1,2 @@\n+one\n+two\n"
+        result = self.verify([{"path": "new.py", "line": 2, "side": "RIGHT", "body": "Check"}], diff)
+        self.assertEqual(result.returncode, 0, result.stderr)
+        result = self.verify([{"path": "new.py", "line": 1, "side": "LEFT", "body": "Check"}], diff)
         self.assertNotEqual(result.returncode, 0)
 
     def test_verify_checks_multiline_comment_start(self):