builtin_dir(): Treat classic classes like types. Use PyDict_Keys instead

tim-one · tim-one · commit 37a309db7086 · 2001-09-04T01:20:04.000Z
of PyMapping_Keys because we know we have a real dict.  Tolerate that
objects may have an attr named "__dict__" that's not a dict (Py_None
popped up during testing).

test_descr.py, test_dir():  Test the new classic-class behavior; beef up
the new-style class test similarly.

test_pyclbr.py, checkModule():  dir(C) is no longer a synonym for
C.__dict__.keys() when C is a classic class (looks like the same thing
that burned distutils! -- should it be *made* a synoym again?  Then it
would be inconsistent with new-style class behavior.).
diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
@@ -183,8 +183,7 @@ def test_dir():
     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).
+    # Try classic classes.
     class C:
         Cdata = 1
         def Cmethod(self): pass
@@ -202,23 +201,45 @@ def Cmethod(self): pass
     class A(C):
         Adata = 1
         def Amethod(self): pass
-    astuff = ['Adata', 'Amethod', '__doc__', '__module__']
-    # This isn't finding C's stuff at all.
+
+    astuff = ['Adata', 'Amethod'] + cstuff
     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)
+    verify(dir(a) == astuff)
+    a.adata = 42
+    a.amethod = lambda self: 3
+    verify(dir(a) == astuff + ['adata', 'amethod'])
+
+    # The same, but with new-style classes.  Since these have object as a
+    # base class, a lot more gets sucked in.
+    def interesting(strings):
+        return [s for s in strings if not s.startswith('_')]
 
-    # The story for new-style classes is quite different.
     class C(object):
         Cdata = 1
         def Cmethod(self): pass
+
+    cstuff = ['Cdata', 'Cmethod']
+    verify(interesting(dir(C)) == cstuff)
+
+    c = C()
+    verify(interesting(dir(c)) == cstuff)
+
+    c.cdata = 2
+    c.cmethod = lambda self: 0
+    verify(interesting(dir(c)) == cstuff + ['cdata', 'cmethod'])
+
     class A(C):
         Adata = 1
         def Amethod(self): pass
-    d = dir(A)
-    for expected in 'Cdata', 'Cmethod', 'Adata', 'Amethod':
-        verify(expected in d)
+
+    astuff = ['Adata', 'Amethod'] + cstuff
+    verify(interesting(dir(A)) == astuff)
+    a = A()
+    verify(interesting(dir(a)) == astuff)
+    a.adata = 42
+    a.amethod = lambda self: 3
+    verify(interesting(dir(a)) == astuff + ['adata', 'amethod'])
 
 binops = {
     'add': '+',
diff --git a/Lib/test/test_pyclbr.py b/Lib/test/test_pyclbr.py
@@ -76,7 +76,7 @@ def checkModule(self, moduleName, module=None, ignore=()):
                 self.assertListEq(real_bases, pyclbr_bases, ignore)
 
                 actualMethods = []
-                for m in dir(py_item):
+                for m in py_item.__dict__.keys():
                     if type(getattr(py_item, m)) == MethodType:
                         actualMethods.append(m)
                 foundMethods = []
diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
@@ -440,9 +440,6 @@ merge_class_dict(PyObject* dict, PyObject* aclass)
 	PyObject *bases;
 
 	assert(PyDict_Check(dict));
-	/* XXX Class objects fail the PyType_Check check.  Don't
-	   XXX know of others. */
-	/* assert(PyType_Check(aclass)); */
 	assert(aclass);
 
 	/* Merge in the type's dict (if any). */
@@ -490,7 +487,7 @@ builtin_dir(PyObject *self, PyObject *args)
 		PyObject *locals = PyEval_GetLocals();
 		if (locals == NULL)
 			goto error;
-		result = PyMapping_Keys(locals);
+		result = PyDict_Keys(locals);
 		if (result == NULL)
 			goto error;
 	}
@@ -500,10 +497,13 @@ builtin_dir(PyObject *self, PyObject *args)
 		masterdict = PyObject_GetAttrString(arg, "__dict__");
 		if (masterdict == NULL)
 			goto error;
+		assert(PyDict_Check(masterdict));
 	}
 
-	/* Elif some form of type, recurse. */
-	else if (PyType_Check(arg)) {
+	/* Elif some form of type or class, grab its dict and its bases.
+	   We deliberately don't suck up its __class__, as methods belonging
+	   to the metaclass would probably be more confusing than helpful. */
+	else if (PyType_Check(arg) || PyClass_Check(arg)) {
 		masterdict = PyDict_New();
 		if (masterdict == NULL)
 			goto error;
@@ -514,28 +514,30 @@ builtin_dir(PyObject *self, PyObject *args)
 	/* Else look at its dict, and the attrs reachable from its class. */
 	else {
 		PyObject *itsclass;
-		/* Create a dict to start with. */
+		/* Create a dict to start with.  CAUTION:  Not everything
+		   responding to __dict__ returns a dict! */
 		masterdict = PyObject_GetAttrString(arg, "__dict__");
 		if (masterdict == NULL) {
 			PyErr_Clear();
 			masterdict = PyDict_New();
-			if (masterdict == NULL)
-				goto error;
+		}
+		else if (!PyDict_Check(masterdict)) {
+			Py_DECREF(masterdict);
+			masterdict = PyDict_New();
 		}
 		else {
 			/* The object may have returned a reference to its
 			   dict, so copy it to avoid mutating it. */
 			PyObject *temp = PyDict_Copy(masterdict);
-			if (temp == NULL)
-				goto error;
 			Py_DECREF(masterdict);
 			masterdict = temp;
 		}
-		/* Merge in attrs reachable from its class. */
+		if (masterdict == NULL)
+			goto error;
+
+		/* Merge in attrs reachable from its class.
+		   CAUTION:  Not all objects have a __class__ attr. */
 		itsclass = PyObject_GetAttrString(arg, "__class__");
-		/* XXX Sometimes this is null!  Like after "class C: pass",
-		   C.__class__ raises AttributeError.  Don't know of other
-		   cases. */
 		if (itsclass == NULL)
 			PyErr_Clear();
 		else {
@@ -550,7 +552,7 @@ builtin_dir(PyObject *self, PyObject *args)
 	if (masterdict != NULL) {
 		/* The result comes from its keys. */
 		assert(result == NULL);
-		result = PyMapping_Keys(masterdict);
+		result = PyDict_Keys(masterdict);
 		if (result == NULL)
 			goto error;
 	}
@@ -578,7 +580,8 @@ static char dir_doc[] =
 "\n"
 "No argument:  the names in the current scope.\n"
 "Module object:  the module attributes.\n"
-"Type object:  its attributes, and recursively the attributes of its bases.\n"
+"Type or class object:  its attributes, and recursively the attributes of\n"
+"    its bases.\n"
 "Otherwise:  its attributes, its class's attributes, and recursively the\n"
 "    attributes of its class's base classes.";
 
