Implement absolute_import.

compiler/imputil.py

@@ -34,7 +34,7 @@ _NATIVE_MODULE_PREFIX = '__go__.'
 class Path(object):
   """Resolves imported modules based on a search path of directories."""
 
-  def __init__(self, gopath, modname, script):
+  def __init__(self, gopath, modname, script, absolute_import):
     self.dirs = []
     if gopath:
       self.dirs.extend(os.path.join(d, 'src', '__python__')
@@ -50,6 +50,7 @@ class Path(object):
     else:
       self.package_dir = None
       self.package_name = None
+    self.absolute_import = absolute_import
 
   def resolve_import(self, modname):
     """Find module on the path returning full module name and script path.
@@ -61,7 +62,7 @@ class Path(object):
       A pair (full_name, script), where full_name is the absolute module name
       and script is the filename of the associate .py file.
     """
-    if self.package_dir:
+    if not self.absolute_import and self.package_dir:
       script = self._find_script(self.package_dir, modname)
       if script:
         return '{}.{}'.format(self.package_name, modname), script
@@ -178,7 +179,7 @@ _FUTURE_FEATURES = (
     'unicode_literals',
 )
 
-_IMPLEMENTED_FUTURE_FEATURES = ('print_function',)
+_IMPLEMENTED_FUTURE_FEATURES = ('absolute_import', 'print_function',)
 
 # These future features are already in the language proper as of 2.6, so
 # importing them via __future__ has no effect.
@@ -188,8 +189,10 @@ _REDUNDANT_FUTURE_FEATURES = ('generators', 'with_statement', 'nested_scopes')
 class FutureFeatures(object):
 
   def __init__(self):
-    for name in _FUTURE_FEATURES:
-      setattr(self, name, False)
+    self.absolute_import = False
+    self.division = False
+    self.print_function = False
+    self.unicode_literals = False
 
 
 def _make_future_features(node):

compiler/imputil_test.py

@@ -72,18 +72,18 @@ class _MaterializedPathTree(object):
 class PathTest(unittest.TestCase):
 
   def testResolveImportEmptyPath(self):
-    path = imputil.Path(None, 'foo', 'foo.py')
+    path = imputil.Path(None, 'foo', 'foo.py', False)
     self.assertEqual(path.resolve_import('bar'), (None, None))
 
   def testResolveImportTopLevelModule(self):
     with _MaterializedPathTree({'bar.py': None}) as tree:
-      path = imputil.Path(tree.rootdir, 'foo', 'foo.py')
+      path = imputil.Path(tree.rootdir, 'foo', 'foo.py', False)
       want = ('bar', os.path.join(tree.pydir, 'bar.py'))
       self.assertEqual(path.resolve_import('bar'), want)
 
   def testResolveImportTopLevelPackage(self):
     with _MaterializedPathTree({'bar/': {'__init__.py': None}}) as tree:
-      path = imputil.Path(tree.rootdir, 'foo', 'foo.py')
+      path = imputil.Path(tree.rootdir, 'foo', 'foo.py', False)
       want = ('bar', os.path.join(tree.pydir, 'bar', '__init__.py'))
       self.assertEqual(path.resolve_import('bar'), want)
 
@@ -95,7 +95,7 @@ class PathTest(unittest.TestCase):
         }
     }
     with _MaterializedPathTree(spec) as tree:
-      path = imputil.Path(tree.rootdir, 'foo', 'foo.py')
+      path = imputil.Path(tree.rootdir, 'foo', 'foo.py', False)
       want = ('bar.baz', os.path.join(tree.pydir, 'bar', 'baz.py'))
       self.assertEqual(path.resolve_import('bar.baz'), want)
 
@@ -104,14 +104,29 @@ class PathTest(unittest.TestCase):
         'bar/': {
             '__init__.py': None,
             'baz.py': None,
-        }
+        },
+        'baz.py': None,
     }
     with _MaterializedPathTree(spec) as tree:
       bar_script = os.path.join(tree.pydir, 'bar', '__init__.py')
-      path = imputil.Path(tree.rootdir, 'bar', bar_script)
+      path = imputil.Path(tree.rootdir, 'bar', bar_script, False)
       want = ('bar.baz', os.path.join(tree.pydir, 'bar', 'baz.py'))
       self.assertEqual(path.resolve_import('baz'), want)
 
+  def testResolveImportPackageModuleAbsoluteImport(self):
+    spec = {
+        'bar/': {
+            '__init__.py': None,
+            'baz.py': None,
+        },
+        'baz.py': None,
+    }
+    with _MaterializedPathTree(spec) as tree:
+      bar_script = os.path.join(tree.pydir, 'bar', '__init__.py')
+      path = imputil.Path(tree.rootdir, 'bar', bar_script, True)
+      want = ('baz', os.path.join(tree.pydir, 'baz.py'))
+      self.assertEqual(path.resolve_import('baz'), want)
+
   def testResolveImportPackageModuleRelativeFromSubModule(self):
     spec = {
         'bar/': {
@@ -122,7 +137,7 @@ class PathTest(unittest.TestCase):
     }
     with _MaterializedPathTree(spec) as tree:
       foo_script = os.path.join(tree.pydir, 'bar', 'foo.py')
-      path = imputil.Path(tree.rootdir, 'bar.foo', foo_script)
+      path = imputil.Path(tree.rootdir, 'bar.foo', foo_script, False)
       want = ('bar.baz', os.path.join(tree.pydir, 'bar', 'baz.py'))
       self.assertEqual(path.resolve_import('baz'), want)
 
@@ -278,8 +293,9 @@ class MakeFutureFeaturesTest(unittest.TestCase):
 class ParseFutureFeaturesTest(unittest.TestCase):
 
   def testFutureFeatures(self):
-    print_function_features = imputil.FutureFeatures()
-    print_function_features.print_function = True
+    print_function_features = {'print_function': True}
+    absolute_import_features = {'absolute_import': True}
+    all_features = {'print_function': True, 'absolute_import': True}
     testcases = [
         ('from __future__ import print_function',
          print_function_features),
@@ -294,13 +310,17 @@ class ParseFutureFeaturesTest(unittest.TestCase):
         from __future__ import print_function, with_statement
         from __future__ import nested_scopes
         """, print_function_features),
+        ('from __future__ import absolute_import',
+         absolute_import_features),
+        ('from __future__ import absolute_import, print_function',
+         all_features),
     ]
 
     for tc in testcases:
       source, want = tc
       mod = pythonparser.parse(textwrap.dedent(source))
       _, got = imputil.parse_future_features(mod)
-      self.assertEqual(want.__dict__, got.__dict__)
+      self.assertEqual(want, got.__dict__)
 
   def testFutureAfterAssignRaises(self):
     source = 'foo = 123\nfrom __future__ import print_function'

tools/grumpc

@@ -64,7 +64,8 @@ def main(args):
     print >> sys.stderr, str(e)
     return 2
 
-  path = imputil.Path(gopath, args.modname, args.script)
+  path = imputil.Path(gopath, args.modname, args.script,
+                      future_features.absolute_import)
   full_package_name = args.modname.replace('.', '/')
   mod_block = block.ModuleBlock(path, full_package_name, args.script,
                                 py_contents, future_features)

tools/pydeps

@@ -36,7 +36,6 @@ def main(args):
   if not gopath:
     print >> sys.stderr, 'GOPATH not set'
     return 1
-  path = imputil.Path(gopath, args.modname, args.script)
 
   with open(args.script) as py_file:
     py_contents = py_file.read()
@@ -48,11 +47,13 @@ def main(args):
     return 2
 
   try:
-    future_node, _ = imputil.parse_future_features(mod)
+    future_node, future_features = imputil.parse_future_features(mod)
   except util.CompileError as e:
     print >> sys.stderr, str(e)
     return 2
 
+  path = imputil.Path(gopath, args.modname, args.script,
+                      future_features.absolute_import)
   visitor = imputil.ImportVisitor(path, future_node)
   try:
     visitor.visit(mod)