⚡ Bolt: Pre-compile Regex Patterns for Performance

.jules/bolt.md

@@ -0,0 +1,3 @@
+## 2024-05-24 - Pre-compile Regex Patterns for Performance
+**Learning:** Python's `re` module internally caches compiled regex patterns, but bypassing this cache lookup by directly executing pre-compiled `re.Pattern` objects (e.g., `p.search(text)`) yields measurable performance improvements in tight loops, especially in safety-critical code executed frequently like `ExecutionSafetyManager.assess_execution`.
+**Action:** When repeatedly applying multiple regex patterns (like in list comprehensions with `any()`), pre-compile them into a tuple of `re.Pattern` objects as class-level attributes using generator expressions. Note that list comprehensions inside a class body don't have access to the class's scope in Python 3, so a generator expression like `tuple(re.compile(p) for p in _PATTERNS)` is required.

libs/safety_manager.py

@@ -180,6 +180,13 @@ class ExecutionSafetyManager:
 		r"\bbash\b",
 	]
 
+	# Pre-compiled regex patterns for performance optimization
+	_WRITE_PATTERNS_COMPILED = tuple(re.compile(p, re.IGNORECASE) for p in _WRITE_PATTERNS)
+	_WRITE_ON_HANDLE_PATTERNS_COMPILED = tuple(re.compile(p, re.IGNORECASE) for p in _WRITE_ON_HANDLE_PATTERNS)
+	_SENSITIVE_POSIX_PREFIXES_COMPILED = tuple(re.compile(p, re.IGNORECASE) for p in _SENSITIVE_POSIX_PREFIXES)
+	_DESTRUCTIVE_PATTERNS_COMPILED = tuple(re.compile(p) for p in _DESTRUCTIVE_PATTERNS)
+	_SHELL_PATTERNS_COMPILED = tuple(re.compile(p) for p in _SHELL_PATTERNS)
+
 	def __init__(self, unsafe_mode: bool = False):
 		self.unsafe_mode = unsafe_mode
 
@@ -228,7 +235,7 @@ def _has_write_operation(self, code: str) -> bool:
 		"""Return True if *code* contains any write operation that must be
 		blocked in SAFE mode.
 		"""
-		return any(re.search(p, code, re.IGNORECASE) for p in self._WRITE_PATTERNS)
+		return any(p.search(code) for p in self._WRITE_PATTERNS_COMPILED)
 
 	# =========================
 	# WRITE-ON-HANDLE DETECTION
@@ -240,7 +247,7 @@ def _has_write_on_handle(self, code: str) -> bool:
 		"""Return True if *code* calls .write() on any object (handle check).
 		This is intentionally only evaluated when an absolute path is present.
 		"""
-		return any(re.search(p, code, re.IGNORECASE) for p in self._WRITE_ON_HANDLE_PATTERNS)
+		return any(p.search(code) for p in self._WRITE_ON_HANDLE_PATTERNS_COMPILED)
 
 	# =========================
 	# HOST ABSOLUTE PATH CHECK
@@ -285,7 +292,7 @@ def _is_host_absolute_path(self, code: str) -> bool:
 
 	def _is_sensitive_posix_path(self, code: str) -> bool:
 		"""Return True if *code* references a sensitive POSIX system path."""
-		return any(re.search(p, code, re.IGNORECASE) for p in self._SENSITIVE_POSIX_PREFIXES)
+		return any(p.search(code) for p in self._SENSITIVE_POSIX_PREFIXES_COMPILED)
 
 	# =========================
 	# MAIN CHECK
@@ -326,15 +333,15 @@ def assess_execution(self, code: str, mode: str) -> Decision:
 		# (shutdown, reboot, mkfs, dd, format, diskpart) in addition to
 		# filesystem deletes.
 		# =========================
-		if any(re.search(p, code_lower) for p in self._DESTRUCTIVE_PATTERNS):
+		if any(p.search(code_lower) for p in self._DESTRUCTIVE_PATTERNS_COMPILED):
 			return Decision(False, ["Destructive operation blocked."])
 
 		# =========================
 		# SHELL BLOCK
 		# BUG FIX #2: Uses _SHELL_PATTERNS with \b word-boundary regex instead
 		# of plain substring `in` check to avoid false positives.
 		# =========================
-		if any(re.search(p, code_lower) for p in self._SHELL_PATTERNS):
+		if any(p.search(code_lower) for p in self._SHELL_PATTERNS_COMPILED):
 			return Decision(False, ["Shell execution is blocked."])
 
 		# =========================
@@ -370,7 +377,7 @@ def is_dangerous_operation(self, code: str) -> bool:
 		if not code or not code.strip():
 			return False
 		code_lower = code.lower()
-		return any(re.search(p, code_lower) for p in self._DESTRUCTIVE_PATTERNS)
+		return any(p.search(code_lower) for p in self._DESTRUCTIVE_PATTERNS_COMPILED)
 
 	# =========================
 	# ARTIFACT EXPORT