make py lib a self-contained directory again

- move and merge _py/ bits back to py/
- fixes all around

--HG--
branch : trunk

testing/plugin/test_pytest_recwarn.py

@@ -0,0 +1,81 @@
+import py
+from py.plugin.pytest_recwarn import WarningsRecorder
+
+def test_WarningRecorder():
+    showwarning = py.std.warnings.showwarning
+    rec = WarningsRecorder()
+    assert py.std.warnings.showwarning != showwarning
+    assert not rec.list
+    py.std.warnings.warn_explicit("hello", UserWarning, "xyz", 13)
+    assert len(rec.list) == 1
+    py.std.warnings.warn(DeprecationWarning("hello"))
+    assert len(rec.list) == 2
+    warn = rec.pop()
+    assert str(warn.message) == "hello"
+    l = rec.list
+    rec.clear()
+    assert len(rec.list) == 0
+    assert l is rec.list
+    py.test.raises(AssertionError, "rec.pop()")
+    rec.finalize()
+    assert showwarning == py.std.warnings.showwarning
+
+def test_recwarn_functional(testdir):
+    reprec = testdir.inline_runsource("""
+        pytest_plugins = 'pytest_recwarn', 
+        import warnings
+        oldwarn = warnings.showwarning
+        def test_method(recwarn):
+            assert warnings.showwarning != oldwarn
+            warnings.warn("hello")
+            warn = recwarn.pop()
+            assert isinstance(warn.message, UserWarning)
+        def test_finalized():
+            assert warnings.showwarning == oldwarn
+    """)
+    res = reprec.countoutcomes()
+    assert tuple(res) == (2, 0, 0), res
+        
+#
+# ============ test py.test.deprecated_call() ==============
+#
+
+def dep(i):
+    if i == 0:
+        py.std.warnings.warn("is deprecated", DeprecationWarning)
+    return 42
+
+reg = {}
+def dep_explicit(i):
+    if i == 0:
+        py.std.warnings.warn_explicit("dep_explicit", category=DeprecationWarning, 
+                                      filename="hello", lineno=3)
+
+def test_deprecated_call_raises():
+    excinfo = py.test.raises(AssertionError, 
+                   "py.test.deprecated_call(dep, 3)")
+    assert str(excinfo).find("did not produce") != -1 
+
+def test_deprecated_call():
+    py.test.deprecated_call(dep, 0)
+
+def test_deprecated_call_ret():
+    ret = py.test.deprecated_call(dep, 0)
+    assert ret == 42
+
+def test_deprecated_call_preserves():
+    r = py.std.warnings.onceregistry.copy()
+    f = py.std.warnings.filters[:]
+    test_deprecated_call_raises()
+    test_deprecated_call()
+    assert r == py.std.warnings.onceregistry
+    assert f == py.std.warnings.filters
+
+def test_deprecated_explicit_call_raises():
+    py.test.raises(AssertionError, 
+                   "py.test.deprecated_call(dep_explicit, 3)")
+
+def test_deprecated_explicit_call():
+    py.test.deprecated_call(dep_explicit, 0)
+    py.test.deprecated_call(dep_explicit, 0)
+