fixes to parser for defer

thirdparty/defer/sugar/_parse.py

@@ -1,10 +1,10 @@
 import sys
+import os
 from ast import (
     AsyncFunctionDef,
     FunctionDef,
 )
 from collections import deque
-from os.path import isabs
 from types import FrameType
 from typing import Any, Callable, Optional, cast
 
@@ -16,21 +16,19 @@ def _is_dunder(name: str) -> bool:
     return name.startswith("__") and name.endswith("__")
 
 
-def _is_excluded_path(filename: str) -> bool:
+_SITE_PACKAGES = "site-packages"
+_VENV = ".venv"
+_THIRDPARTY = "thirdparty"
+_SRC_WIN = "\\src\\"
+_SRC_UNIX = "/src/"
+
+
+def _is_our_code(filename: str) -> bool:
     if not filename:
+        return False
+    if _SRC_WIN in filename or _SRC_UNIX in filename:
         return True
-    return (
-        filename.startswith(sys.base_exec_prefix)
-        or filename.startswith(sys.base_prefix)
-        or filename.startswith(sys.exec_prefix)
-        or filename.startswith(sys.prefix)
-        or ".venv" in filename
-        or filename.startswith("<frozen ")
-        or filename.startswith("<string>")
-        or filename.startswith("<pytest ")
-        or "thirdparty" in filename
-        or "__future__" in filename
-    )
+    return False
 
 
 class _ParseDefer:
@@ -41,65 +39,70 @@ class _ParseDefer:
         self.pending: deque[Executing] = deque()
 
     def __call__(self, frame: FrameType, event: str, arg: Any):
-        try:
-            self._do_call(frame, event, arg)
-        except Exception:
-            pass
-        return self
-
-    def _do_call(self, frame: FrameType, event: str, arg: Any):
         self.tracefn(frame, event, arg)
 
         try:
             filename = frame.f_code.co_filename
+            if not filename:
+                return self
+            if _SITE_PACKAGES in filename or _VENV in filename or _THIRDPARTY in filename:
+                return self
+            if not _is_our_code(filename):
+                return self
         except Exception:
-            return
-
-        if _is_excluded_path(filename):
-            return
-
-        if not isabs(filename):
-            return
+            pass
 
         if event != "line":
-            return
+            return self
 
         try:
             from executing.executing import Executing, Source
         except ImportError:
-            return
+            return self
 
         try:
             exc = Source.executing(frame)
         except Exception:
-            return
+            return self
 
         if not (stmt := next(iter(exc.statements), None)):
-            return
+            return self
         if isinstance(stmt, (AsyncFunctionDef, FunctionDef)):
             if _is_dunder(stmt.name):
-                return
+                return self
             self.pending.append(exc)
-            return
+            return self
         if not self.pending or frame.f_back is not self.pending[-1].frame.f_back:
-            return
+            return self
 
         stmts = self.pending.pop().statements
         node = cast(FunctionDef | AsyncFunctionDef, next(iter(stmts)))
         fn_name = node.name
 
         if fn_name not in frame.f_locals:
-            return
+            return self
         fn = frame.f_locals[fn_name]
 
-        if fn.__module__ in sys.stdlib_module_names:
-            return
-        if fn.__code__.co_freevars:
-            raise FreeVarsError(fn)
+        if not callable(fn):
+            return self
+        try:
+            code = fn.__code__
+        except AttributeError:
+            return self
+
+        try:
+            mod = fn.__module__
+        except AttributeError:
+            return self
+        if mod in sys.stdlib_module_names:
+            return self
+        if code.co_freevars:
+            return self
         if not (ast := RewriteDefer.transform(node)):
-            return
+            return self
 
         locals = frame.f_locals.copy()
         del locals[fn_name]
         exec(compile(ast, frame.f_code.co_filename, "exec"), frame.f_globals, locals)
         frame.f_locals[fn_name].__code__ = locals[fn_name].__code__
+        return self