AppPkg/Applications/Python: Add Python 2.7.2 sources since the release of Python...

[mirror_edk2.git] / AppPkg / Applications / Python / Python-2.7.2 / Demo / metaclasses / Trace.py

diff --git a/AppPkg/Applications/Python/Python-2.7.2/Demo/metaclasses/Trace.py b/AppPkg/Applications/Python/Python-2.7.2/Demo/metaclasses/Trace.py
new file mode 100644 (file)
index 0000000..b02d05a
--- /dev/null
+++ b/AppPkg/Applications/Python/Python-2.7.2/Demo/metaclasses/Trace.py
@@ -0,0 +1,144 @@
+"""Tracing metaclass.\r
+\r
+XXX This is very much a work in progress.\r
+\r
+"""\r
+\r
+import types, sys\r
+\r
+class TraceMetaClass:\r
+    """Metaclass for tracing.\r
+\r
+    Classes defined using this metaclass have an automatic tracing\r
+    feature -- by setting the __trace_output__ instance (or class)\r
+    variable to a file object, trace messages about all calls are\r
+    written to the file.  The trace formatting can be changed by\r
+    defining a suitable __trace_call__ method.\r
+\r
+    """\r
+\r
+    __inited = 0\r
+\r
+    def __init__(self, name, bases, dict):\r
+        self.__name__ = name\r
+        self.__bases__ = bases\r
+        self.__dict = dict\r
+        # XXX Can't define __dict__, alas\r
+        self.__inited = 1\r
+\r
+    def __getattr__(self, name):\r
+        try:\r
+            return self.__dict[name]\r
+        except KeyError:\r
+            for base in self.__bases__:\r
+                try:\r
+                    return base.__getattr__(name)\r
+                except AttributeError:\r
+                    pass\r
+            raise AttributeError, name\r
+\r
+    def __setattr__(self, name, value):\r
+        if not self.__inited:\r
+            self.__dict__[name] = value\r
+        else:\r
+            self.__dict[name] = value\r
+\r
+    def __call__(self, *args, **kw):\r
+        inst = TracingInstance()\r
+        inst.__meta_init__(self)\r
+        try:\r
+            init = inst.__getattr__('__init__')\r
+        except AttributeError:\r
+            init = lambda: None\r
+        apply(init, args, kw)\r
+        return inst\r
+\r
+    __trace_output__ = None\r
+\r
+class TracingInstance:\r
+    """Helper class to represent an instance of a tracing class."""\r
+\r
+    def __trace_call__(self, fp, fmt, *args):\r
+        fp.write((fmt+'\n') % args)\r
+\r
+    def __meta_init__(self, klass):\r
+        self.__class = klass\r
+\r
+    def __getattr__(self, name):\r
+        # Invoked for any attr not in the instance's __dict__\r
+        try:\r
+            raw = self.__class.__getattr__(name)\r
+        except AttributeError:\r
+            raise AttributeError, name\r
+        if type(raw) != types.FunctionType:\r
+            return raw\r
+        # It's a function\r
+        fullname = self.__class.__name__ + "." + name\r
+        if not self.__trace_output__ or name == '__trace_call__':\r
+            return NotTracingWrapper(fullname, raw, self)\r
+        else:\r
+            return TracingWrapper(fullname, raw, self)\r
+\r
+class NotTracingWrapper:\r
+    def __init__(self, name, func, inst):\r
+        self.__name__ = name\r
+        self.func = func\r
+        self.inst = inst\r
+    def __call__(self, *args, **kw):\r
+        return apply(self.func, (self.inst,) + args, kw)\r
+\r
+class TracingWrapper(NotTracingWrapper):\r
+    def __call__(self, *args, **kw):\r
+        self.inst.__trace_call__(self.inst.__trace_output__,\r
+                                 "calling %s, inst=%s, args=%s, kw=%s",\r
+                                 self.__name__, self.inst, args, kw)\r
+        try:\r
+            rv = apply(self.func, (self.inst,) + args, kw)\r
+        except:\r
+            t, v, tb = sys.exc_info()\r
+            self.inst.__trace_call__(self.inst.__trace_output__,\r
+                                     "returning from %s with exception %s: %s",\r
+                                     self.__name__, t, v)\r
+            raise t, v, tb\r
+        else:\r
+            self.inst.__trace_call__(self.inst.__trace_output__,\r
+                                     "returning from %s with value %s",\r
+                                     self.__name__, rv)\r
+            return rv\r
+\r
+Traced = TraceMetaClass('Traced', (), {'__trace_output__': None})\r
+\r
+\r
+def _test():\r
+    global C, D\r
+    class C(Traced):\r
+        def __init__(self, x=0): self.x = x\r
+        def m1(self, x): self.x = x\r
+        def m2(self, y): return self.x + y\r
+        __trace_output__ = sys.stdout\r
+    class D(C):\r
+        def m2(self, y): print "D.m2(%r)" % (y,); return C.m2(self, y)\r
+        __trace_output__ = None\r
+    x = C(4321)\r
+    print x\r
+    print x.x\r
+    print x.m1(100)\r
+    print x.m1(10)\r
+    print x.m2(33)\r
+    print x.m1(5)\r
+    print x.m2(4000)\r
+    print x.x\r
+\r
+    print C.__init__\r
+    print C.m2\r
+    print D.__init__\r
+    print D.m2\r
+\r
+    y = D()\r
+    print y\r
+    print y.m1(10)\r
+    print y.m2(100)\r
+    print y.x\r
+\r
+if __name__ == '__main__':\r
+    _test()\r