pass trough annotated exceptions

_pytest/monkeypatch.py

@@ -2,6 +2,7 @@
 
 import os, sys
 import re
+import pytest
 
 from py.builtin import _basestring
 
@@ -52,17 +53,22 @@ def resolve(name):
                     raise ImportError(
                         'import error in %s: %s' % (used, ex)
                     )
-            try:
-                found = getattr(found, part)
-            except AttributeError:
-                raise AttributeError(
-                    '%r object at %s has no attribute %r' %(
-                        type(found).__name__, used, part
-                    )
-                )
+            found = annotated_getattr(found, part, used)
     return found
 
 
+def annotated_getattr(obj, name, ann):
+    try:
+        obj = getattr(obj, name)
+    except AttributeError:
+        raise AttributeError(
+                '%r object at %s has no attribute %r' % (
+                    type(obj).__name__, ann, name
+                )
+        )
+    return obj
+
+
 def derive_importpath(import_path, raising):
     if not isinstance(import_path, _basestring) or "." not in import_path:
         raise TypeError("must be absolute import path string, not %r" %
@@ -70,7 +76,7 @@ def derive_importpath(import_path, raising):
     module, attr = import_path.rsplit('.', 1)
     target = resolve(module)
     if raising:
-        getattr(target, attr)
+        annotated_getattr(target, attr, ann=module)
     return attr, target
 
 

testing/test_monkeypatch.py

@@ -62,11 +62,11 @@ class TestSetattrWithImportPath:
         pytest.raises(TypeError, lambda: monkeypatch.setattr(None, None))
 
     def test_unknown_import(self, monkeypatch):
-        pytest.raises(pytest.fail.Exception,
+        pytest.raises(ImportError,
                       lambda: monkeypatch.setattr("unkn123.classx", None))
 
     def test_unknown_attr(self, monkeypatch):
-        pytest.raises(pytest.fail.Exception,
+        pytest.raises(AttributeError,
                       lambda: monkeypatch.setattr("os.path.qweqwe", None))
 
     def test_unknown_attr_non_raising(self, monkeypatch):
@@ -283,7 +283,7 @@ def test_importerror(testdir):
     """))
     result = testdir.runpytest()
     result.stdout.fnmatch_lines("""
-        *import error in package.a.x: No module named {0}doesnotexist{0}*
+        *import error in package.a: No module named {0}doesnotexist{0}*
     """.format("'" if sys.version_info > (3, 0) else ""))