feat: include filename and line number in logs/errors

pyproject.toml

@@ -8,6 +8,7 @@ extend-select = [
     "B", # bugbear
     "FIX", # disallow FIXME/TODO comments
     "F", # pyflakes
+    "T20", # flake8-print
 ]
 
 [tool.pyright]

src/queryspy/listeners.py

@@ -9,6 +9,8 @@
 from django.conf import settings
 from django.db import models
 
+from queryspy.util import get_caller
+
 from .errors import NPlusOneError, QuerySpyError
 
 ModelAndField = tuple[Type[models.Model], str]
@@ -60,6 +62,8 @@ def _alert(self, model: type[models.Model], field: str, message: str):
         if is_allowlisted:
             return
 
+        caller = get_caller()
+        message = f"{message} at {caller.filename}:{caller.lineno} in {caller.function}"
         if should_error:
             raise self.error_class(message)
         else:

src/queryspy/util.py

@@ -0,0 +1,15 @@
+import inspect
+
+PATTERNS = ["site-packages", "queryspy/listeners.py", "queryspy/patch.py"]
+
+
+def get_caller() -> inspect.FrameInfo:
+    """
+    Returns the filename and line number of the current caller,
+    excluding any code in site-packages or queryspy.
+    """
+    return next(
+        frame
+        for frame in inspect.stack()[1:]
+        if not any(pattern in frame.filename for pattern in PATTERNS)
+    )

tests/test_listeners.py

@@ -1,4 +1,5 @@
 import logging
+import re
 
 import pytest
 from djangoproject.social.models import Post, User
@@ -20,7 +21,26 @@ def test_can_log_errors(settings, caplog):
     with caplog.at_level(logging.WARNING):
         for user in User.objects.all():
             _ = list(user.posts.all())
-        assert "N+1 detected on User.posts" in caplog.text
+        assert (
+            re.search(
+                r"N\+1 detected on User\.posts at .*\/test_listeners\.py:23 in test_can_log_errors",
+                caplog.text,
+            )
+            is not None
+        ), f"{caplog.text} does not match regex"
+
+
+@queryspy_context()
+def test_errors_include_caller():
+    [user_1, user_2] = UserFactory.create_batch(2)
+    PostFactory.create(author=user_1)
+    PostFactory.create(author=user_2)
+    with pytest.raises(
+        NPlusOneError,
+        match=r"N\+1 detected on User\.posts at .*\/test_listeners\.py:43 in test_errors_include_caller",
+    ):
+        for user in User.objects.all():
+            _ = list(user.posts.all())
 
 
 @queryspy_context()