Add support for discovering .pth file created by certain namespace packages.

8 files changed, 47 insertions, 4 deletions

diff --git a/astroid/modutils.py b/astroid/modutils.py
index 77081b5b..3334e1e3 100644
--- a/astroid/modutils.py
+++ b/astroid/modutils.py
@@ -742,6 +742,22 @@ class ImpFinder(Finder):
         return path
 
 
+class DynamicImpFinder(ImpFinder):
+
+    def find_module(self, modname, module_parts, processed, submodule_path):
+        if _is_namespace(modname) and modname in sys.modules:
+            submodule_path = sys.modules[modname].__path__
+            return ModuleSpec(name=modname, location='',
+                              origin='namespace',
+                              type=ModuleType.PY_NAMESPACE,
+                              submodule_search_locations=submodule_path)
+
+
+    def contribute_to_path(self, spec, processed):
+        return spec.submodule_search_locations
+
+
+
 class ZipFinder(Finder):
 
     def __init__(self, path):
@@ -776,12 +792,17 @@ class PEP420SpecFinder(Finder):
             return spec.submodule_search_locations
         return None
 
+_SPEC_FINDERS = (
+    ImpFinder,
+    ZipFinder,
+)
+if _HAS_MACHINERY and sys.version_info[:2] > (3, 3):
+    _SPEC_FINDERS += (PEP420SpecFinder, )
+_SPEC_FINDERS += (DynamicImpFinder, )
 
-def _find_spec_with_path(search_path, modname, module_parts, processed, submodule_path):
-    finders = [finder(search_path) for finder in (ImpFinder, ZipFinder)]
-    if _HAS_MACHINERY and sys.version_info[:2] > (3, 3):
-        finders.append(PEP420SpecFinder(search_path))
 
+def _find_spec_with_path(search_path, modname, module_parts, processed, submodule_path):
+    finders = [finder(search_path) for finder in _SPEC_FINDERS]
     for finder in finders:
         spec = finder.find_module(modname, module_parts, processed, submodule_path)
         if spec is None:
diff --git a/astroid/tests/testdata/python2/data/foogle/fax/__init__.py b/astroid/tests/testdata/python2/data/foogle/fax/__init__.py
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/astroid/tests/testdata/python2/data/foogle/fax/__init__.py
diff --git a/astroid/tests/testdata/python2/data/foogle/fax/a.py b/astroid/tests/testdata/python2/data/foogle/fax/a.py
new file mode 100644
index 00000000..3d2b4b14
--- /dev/null
+++ b/astroid/tests/testdata/python2/data/foogle/fax/a.py
@@ -0,0 +1 @@
+x = 1
\ No newline at end of file
diff --git a/astroid/tests/testdata/python2/data/foogle_fax-0.12.5-py2.7-nspkg.pth b/astroid/tests/testdata/python2/data/foogle_fax-0.12.5-py2.7-nspkg.pth
new file mode 100644
index 00000000..d3cb4591
--- /dev/null
+++ b/astroid/tests/testdata/python2/data/foogle_fax-0.12.5-py2.7-nspkg.pth
@@ -0,0 +1 @@
+import sys, types, os;p = os.path.join(sys._getframe(1).f_locals['sitedir'], *('foogle',));ie = os.path.exists(os.path.join(p,'__init__.py'));m = not ie and sys.modules.setdefault('foogle', types.ModuleType('foogle'));mp = (m or []) and m.__dict__.setdefault('__path__',[]);(p not in mp) and mp.append(p)
diff --git a/astroid/tests/testdata/python3/data/foogle/fax/__init__.py b/astroid/tests/testdata/python3/data/foogle/fax/__init__.py
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/astroid/tests/testdata/python3/data/foogle/fax/__init__.py
diff --git a/astroid/tests/testdata/python3/data/foogle/fax/a.py b/astroid/tests/testdata/python3/data/foogle/fax/a.py
new file mode 100644
index 00000000..3d2b4b14
--- /dev/null
+++ b/astroid/tests/testdata/python3/data/foogle/fax/a.py
@@ -0,0 +1 @@
+x = 1
\ No newline at end of file
diff --git a/astroid/tests/testdata/python3/data/foogle_fax-0.12.5-py2.7-nspkg.pth b/astroid/tests/testdata/python3/data/foogle_fax-0.12.5-py2.7-nspkg.pth
new file mode 100644
index 00000000..d3cb4591
--- /dev/null
+++ b/astroid/tests/testdata/python3/data/foogle_fax-0.12.5-py2.7-nspkg.pth
@@ -0,0 +1 @@
+import sys, types, os;p = os.path.join(sys._getframe(1).f_locals['sitedir'], *('foogle',));ie = os.path.exists(os.path.join(p,'__init__.py'));m = not ie and sys.modules.setdefault('foogle', types.ModuleType('foogle'));mp = (m or []) and m.__dict__.setdefault('__path__',[]);(p not in mp) and mp.append(p)
diff --git a/astroid/tests/unittest_manager.py b/astroid/tests/unittest_manager.py
index 34c9ef8f..3b145853 100644
--- a/astroid/tests/unittest_manager.py
+++ b/astroid/tests/unittest_manager.py
@@ -7,9 +7,11 @@
 
 import os
 import platform
+import site
 import sys
 import unittest
 
+import pkg_resources
 import six
 
 import astroid
@@ -120,6 +122,22 @@ class AstroidManagerTest(resources.SysPathSetup,
             for _ in range(2):
                 sys.path.pop(0)
 
+    def test_namespace_package_pth_support(self):
+        directory = os.path.join(resources.DATA_DIR, 'data')
+        pth = 'foogle_fax-0.12.5-py2.7-nspkg.pth'
+        site.addpackage(directory, pth, [])
+        pkg_resources._namespace_packages['foogle'] = []
+        try:
+            module = self.manager.ast_from_module_name('foogle.fax')
+            submodule = next(module.igetattr('a'))
+            value = next(submodule.igetattr('x'))
+            self.assertIsInstance(value, astroid.Const)
+            with self.assertRaises(exceptions.AstroidImportError):
+                self.manager.ast_from_module_name('foogle.moogle')
+        finally:
+            del pkg_resources._namespace_packages['foogle']
+            sys.modules.pop('foogle')
+
     def _test_ast_from_zip(self, archive):
         origpath = sys.path[:]
         sys.modules.pop('mypypa', None)