Merge lp:~pyflakes-dev/pyflakes/1107587-add-builtins into lp:pyflakes

[Florent]

Add flexibility for the magic built-ins.

=== modified file 'NEWS.txt'
--- NEWS.txt	2013-01-27 15:09:36 +0000
+++ NEWS.txt	2013-01-28 07:35:32 +0000
@@ -6,6 +6,7 @@
   - Allow function redefinition for modern property construction via
     property.setter/deleter.
   - Do not report undefined name in __all__ if import * is used.
+  - Support specifying additional built-ins in `Checker` constructor.
   - Handle problems with the encoding of source files.
   - Remove dependency on Twisted for the tests.
   - Support `python setup.py test` and `python setup.py develop`.
 
=== modified file 'pyflakes/checker.py'
--- pyflakes/checker.py	2013-01-27 15:04:53 +0000
+++ pyflakes/checker.py	2013-01-28 07:35:32 +0000
@@ -187,13 +187,16 @@
 
     nodeDepth = 0
     traceTree = False
+    builtIns = set(dir(builtins)) | set(_MAGIC_GLOBALS)
 
-    def __init__(self, tree, filename='(none)'):
+    def __init__(self, tree, filename='(none)', builtins=None):
         self._deferredFunctions = []
         self._deferredAssignments = []
         self.deadScopes = []
         self.messages = []
         self.filename = filename
+        if builtins:
+            self.builtIns = self.builtIns.union(builtins)
         self.scopeStack = [ModuleScope()]
         self.futuresAllowed = True
         self.handleChildren(tree)
@@ -351,7 +354,7 @@
         try:
             self.scopeStack[0][name].used = (self.scope, node.lineno)
         except KeyError:
-            if ((not hasattr(builtins, name)) and name not in _MAGIC_GLOBALS and not importStarred):
+            if not importStarred and name not in self.builtIns:
                 if (os.path.basename(self.filename) == '__init__.py' and name == '__path__'):
                     # the special name __path__ is valid only in packages
                     pass