Fix getting line number with nasty __getattr__.

When an object has a custom __getattr__ which always returns a non-int, we
tried to get compat_co_firstlineno from it and checked it was a integer, which
caused an exception if such a class is mistakenly collected.

If we still mistakenly collect such a class (which is likely to be something
other than a test), we now skip it with a warning (because it probably has an
__init__) instead of producing an error.

See #1204.

CHANGELOG

@@ -6,6 +6,9 @@
   module. Thanks Mikhail Chernykh for the report and Bruno Oliveira for the
   PR.
 
+- fix #1204: another error when collecting with a nasty __getattr__().
+  Thanks Florian Bruhin for the PR.
+
 2.8.3
 -----
 

_pytest/python.py

@@ -384,12 +384,13 @@ class PyobjMixin(PyobjContext):
     def reportinfo(self):
         # XXX caching?
         obj = self.obj
-        if hasattr(obj, 'compat_co_firstlineno'):
+        compat_co_firstlineno = getattr(obj, 'compat_co_firstlineno', None)
+        if isinstance(compat_co_firstlineno, int):
             # nose compatibility
             fspath = sys.modules[obj.__module__].__file__
             if fspath.endswith(".pyc"):
                 fspath = fspath[:-1]
-            lineno = obj.compat_co_firstlineno
+            lineno = compat_co_firstlineno
         else:
             fspath, lineno = getfslineno(obj)
         modpath = self.getmodpath()

testing/python/collect.py

@@ -880,6 +880,21 @@ class TestReportInfo:
                     pass
        """
 
+    def test_reportinfo_with_nasty_getattr(self, testdir):
+        # https://github.com/pytest-dev/pytest/issues/1204
+        modcol = testdir.getmodulecol("""
+            # lineno 0
+            class TestClass:
+                def __getattr__(self, name):
+                    return "this is not an int"
+
+                def test_foo(self):
+                    pass
+        """)
+        classcol = testdir.collect_by_name(modcol, "TestClass")
+        instance = classcol.collect()[0]
+        fspath, lineno, msg = instance.reportinfo()
+
 
 def test_customized_python_discovery(testdir):
     testdir.makeini("""