Make dir() wordier (see the new docstring). The new behavior is a mixed

bag.  It's clearly wrong for classic classes, at heart because a classic
class doesn't have a __class__ attribute, and I'm unclear on whether
that's feature or bug.  I'll repair this once I find out (in the
meantime, dir() applied to classic classes won't find the base classes,
while dir() applied to a classic-class instance *will* find the base
classes but not *their* base classes).

Please give the new dir() a try and see whether you love it or hate it.
The new dir([]) behavior is something I could come to love.  Here's
something to hate:

>>> class C:
...     pass
...
>>> c = C()
>>> dir(c)
['__doc__', '__module__']
>>>

The idea that an instance has a __doc__ attribute is jarring (of course
it's really c.__class__.__doc__ == C.__doc__; likewise for __module__).

OTOH, the code already has too many special cases, and dir(x) doesn't
have a compelling or clear purpose when x isn't a module.

3 files changed, 55 insertions, 11 deletions

diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index f6b9e1b..ee924dc 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -172,6 +172,54 @@ def dict_constructor():
     d = dictionary(mapping=Mapping())
     verify(d == Mapping.dict)
 
+def test_dir():
+    if verbose:
+        print "Testing dir() ..."
+    junk = 12
+    verify(dir() == ['junk'])
+    del junk
+
+    # Just make sure these don't blow up!
+    for arg in 2, 2L, 2j, 2e0, [2], "2", u"2", (2,), {2:2}, type, test_dir:
+        dir(arg)
+
+    # Check some details here because classic classes aren't working
+    # reasonably, and I want this to fail (eventually).
+    class C:
+        Cdata = 1
+        def Cmethod(self): pass
+
+    cstuff = ['Cdata', 'Cmethod', '__doc__', '__module__']
+    verify(dir(C) == cstuff)
+
+    c = C()  # c.__doc__ is an odd thing to see here; ditto c.__module__.
+    verify(dir(c) == cstuff)
+
+    c.cdata = 2
+    c.cmethod = lambda self: 0
+    verify(dir(c) == cstuff + ['cdata', 'cmethod'])
+
+    class A(C):
+        Adata = 1
+        def Amethod(self): pass
+    astuff = ['Adata', 'Amethod', '__doc__', '__module__']
+    # This isn't finding C's stuff at all.
+    verify(dir(A) == astuff)
+    # But this is!  It's because a.__class__ exists but A.__class__ doesn't.
+    a = A()
+    verify(dir(a) == astuff[:2] + cstuff)
+
+    # The story for new-style classes is quite different.
+    class C(object):
+        Cdata = 1
+        def Cmethod(self): pass
+    class A(C):
+        Adata = 1
+        def Amethod(self): pass
+    d = dir(A)
+    for expected in 'Cdata', 'Cmethod', 'Adata', 'Amethod':
+        verify(expected in d)
+
 binops = {
     'add': '+',
     'sub': '-',
@@ -1349,6 +1397,7 @@ def all():
     lists()
     dicts()
     dict_constructor()
+    test_dir()
     ints()
     longs()
     floats()
diff --git a/Lib/test/test_descrtut.py b/Lib/test/test_descrtut.py
index edb0388..121eed5 100644
--- a/Lib/test/test_descrtut.py
+++ b/Lib/test/test_descrtut.py
@@ -97,14 +97,15 @@ just like classic classes:
     >>> a.default = -1000
     >>> print a["noway"]
     -1000
-    >>> print dir(a)
-    ['default']
+    >>> 'default' in dir(a)
+    1
     >>> a.x1 = 100
     >>> a.x2 = 200
     >>> print a.x1
     100
-    >>> print dir(a)
-    ['default', 'x1', 'x2']
+    >>> d = dir(a)
+    >>> 'default' in d and 'x1' in d and 'x2' in d
+    1
     >>> print a.__dict__
     {'default': -1000, 'x2': 200, 'x1': 100}
     >>>
diff --git a/Lib/test/test_generators.py b/Lib/test/test_generators.py
index 947e26f..0e9d060 100644
--- a/Lib/test/test_generators.py
+++ b/Lib/test/test_generators.py
@@ -383,14 +383,8 @@ From the Iterators list, about the types of these things.
 >>> i = g()
 >>> type(i)
 <type 'generator'>
-
-XXX dir(object) *generally* doesn't return useful stuff in descr-branch.
->>> dir(i)
-[]
-
-Was hoping to see this instead:
+>>> [s for s in dir(i) if not s.startswith('_')]
 ['gi_frame', 'gi_running', 'next']
-
 >>> print i.next.__doc__
 x.next() -> the next value, or raise StopIteration
 >>> iter(i) is i