Add a few tests for pydoc.

This is a modified version of a patch proposed by Humberto Diogenes
in the discussion of issue1883.

I will merge manually this change into the py3k branch: the tests must be adapted.
diff --git a/Lib/test/test_pydoc.py b/Lib/test/test_pydoc.py
new file mode 100644
index 0000000..8f0dc73
--- /dev/null
+++ b/Lib/test/test_pydoc.py
@@ -0,0 +1,33 @@
+from test import test_support

+import unittest

+import pydoc

+

+class TestDescriptions(unittest.TestCase):

+    def test_module(self):

+        # Check that pydocfodder module can be described

+        import pydocfodder

+        doc = pydoc.render_doc(pydocfodder)

+        assert "pydocfodder" in doc

+

+    def test_classic_class(self):

+        class C: "Classic class"

+        c = C()

+        self.failUnlessEqual(pydoc.describe(C), 'class C')

+        self.failUnlessEqual(pydoc.describe(c), 'instance of C')

+        self.failUnless('instance of C in module test.test_pydoc'

+                        in pydoc.render_doc(c))

+

+    def test_class(self):

+        class C(object): "New-style class"

+        c = C()

+

+        self.failUnlessEqual(pydoc.describe(C), 'class C')

+        self.failUnlessEqual(pydoc.describe(c), 'C')

+        self.failUnless('C in module test.test_pydoc object'

+                        in pydoc.render_doc(c))

+

+def test_main():

+    test_support.run_unittest(TestDescriptions)

+

+if __name__ == "__main__":

+    unittest.main()