Workaround for #3742

src/_pytest/main.py

@@ -482,6 +482,8 @@ def collect(self):
             self.trace.root.indent -= 1
 
     def _collect(self, arg):
+        from _pytest.python import Package
+
         names = self._parsearg(arg)
         argpath = names.pop(0)
         paths = []
@@ -503,7 +505,7 @@ def _collect(self, arg):
                             root = self._node_cache[pkginit]
                         else:
                             col = root._collectfile(pkginit)
-                            if col:
+                            if col and isinstance(col, Package):
                                 root = col[0]
                                 self._node_cache[root.fspath] = root
 

testing/example_scripts/fixtures/custom_item/conftest.py

@@ -0,0 +1,10 @@
+import pytest
+
+
+class CustomItem(pytest.Item, pytest.File):
+    def runtest(self):
+        pass
+
+
+def pytest_collect_file(path, parent):
+    return CustomItem(path, parent)

testing/example_scripts/fixtures/custom_item/foo/test_foo.py

@@ -0,0 +1,2 @@
+def test():
+    pass

testing/python/fixture.py

@@ -1619,6 +1619,11 @@ def test_package(one):
         reprec = testdir.inline_run()
         reprec.assertoutcome(passed=2)
 
+    def test_collect_custom_items(self, testdir):
+        testdir.copy_example("fixtures/custom_item")
+        result = testdir.runpytest("foo")
+        result.stdout.fnmatch_lines("*passed*")
+
 
 class TestAutouseDiscovery(object):
     @pytest.fixture

testing/test_collection.py

@@ -647,7 +647,7 @@ def test_pkgfile(self, testdir):
         col = testdir.getnode(config, x)
         assert isinstance(col, pytest.Module)
         assert col.name == "x.py"
-        assert col.parent.parent.parent is None
+        assert col.parent.parent is None
         for col in col.listchain():
             assert col.config is config