add new python modules

4 files changed, 170 insertions, 2 deletions

diff --git a/Makefile.am b/Makefile.am
index 5c21de5..f341d7a 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -48,7 +48,12 @@ EXTRA_DIST += docs buildsys-build.spec
 dist_libexec_SCRIPTS = src/mock.py
 man_MANS = docs/mock.1
 
-pkgpython_PYTHON = src/mock/util.py src/mock/__init__.py src/mock/backend.py
+pkgpython_PYTHON = \
+	src/mock/__init__.py \
+	src/mock/util.py \
+	src/mock/decorator.py \
+	src/mock/trace_decorator.py \
+	src/mock/backend.py
 
 src/mock.py: configure.ac Makefile.am src/mock.py
 	echo Updating $@, current pwd: $$(pwd)
diff --git a/Makefile.in b/Makefile.in
index 9969d5e..286587f 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -275,7 +275,13 @@ mocketcdir = $(sysconfdir)/mock
 dist_mocketc_DATA = $(wildcard etc/*.cfg) etc/logging.ini
 dist_libexec_SCRIPTS = src/mock.py
 man_MANS = docs/mock.1
-pkgpython_PYTHON = src/mock/util.py src/mock/__init__.py src/mock/backend.py
+pkgpython_PYTHON = \
+	src/mock/__init__.py \
+	src/mock/util.py \
+	src/mock/decorator.py \
+	src/mock/trace_decorator.py \
+	src/mock/backend.py
+
 all: all-recursive
 
 .SUFFIXES:
diff --git a/src/mock/decorator.py b/src/mock/decorator.py
new file mode 100755
index 0000000..4958a52
--- /dev/null
+++ b/src/mock/decorator.py
@@ -0,0 +1,124 @@
+## The basic trick is to generate the source code for the decorated function
+## with the right signature and to evaluate it.
+## Uncomment the statement 'print >> sys.stderr, func_src'  in _decorate
+## to understand what is going on.
+
+__all__ = ["decorator", "update_wrapper", "getinfo"]
+
+import inspect, sys
+
+def getinfo(func):
+    """
+    Returns an info dictionary containing:
+    - name (the name of the function : str)
+    - argnames (the names of the arguments : list)
+    - defaults (the values of the default arguments : tuple)
+    - signature (the signature : str)
+    - doc (the docstring : str)
+    - module (the module name : str)
+    - dict (the function __dict__ : str)
+
+    >>> def f(self, x=1, y=2, *args, **kw): pass
+
+    >>> info = getinfo(f)
+
+    >>> info["name"]
+    'f'
+    >>> info["argnames"]
+    ['self', 'x', 'y', 'args', 'kw']
+
+    >>> info["defaults"]
+    (1, 2)
+
+    >>> info["signature"]
+    'self, x, y, *args, **kw'
+    """
+    assert inspect.ismethod(func) or inspect.isfunction(func)
+    regargs, varargs, varkwargs, defaults = inspect.getargspec(func)
+    argnames = list(regargs)
+    if varargs:
+        argnames.append(varargs)
+    if varkwargs:
+        argnames.append(varkwargs)
+    signature = inspect.formatargspec(regargs, varargs, varkwargs, defaults,
+                                      formatvalue=lambda value: "")[1:-1]
+    return dict(name=func.__name__, argnames=argnames, signature=signature,
+                defaults = func.func_defaults, doc=func.__doc__,
+                module=func.__module__, dict=func.__dict__,
+                globals=func.func_globals, closure=func.func_closure)
+
+def update_wrapper(wrapper, wrapped, create=False):
+    """
+    An improvement over functools.update_wrapper. By default it works the
+    same, but if the 'create' flag is set, generates a copy of the wrapper
+    with the right signature and update the copy, not the original.
+    Moreovoer, 'wrapped' can be a dictionary with keys 'name', 'doc', 'module',
+    'dict', 'defaults'.
+    """
+    if isinstance(wrapped, dict):
+        infodict = wrapped
+    else: # assume wrapped is a function
+        infodict = getinfo(wrapped)
+    assert not '_wrapper_' in infodict["argnames"], \
+           '"_wrapper_" is a reserved argument name!'
+    if create: # create a brand new wrapper with the right signature
+        src = "lambda %(signature)s: _wrapper_(%(signature)s)" % infodict
+        # import sys; print >> sys.stderr, src # for debugging purposes
+        wrapper = eval(src, dict(_wrapper_=wrapper))
+    try:
+        wrapper.__name__ = infodict['name']
+    except: # Python version < 2.4
+        pass
+    wrapper.__doc__ = infodict['doc']
+    wrapper.__module__ = infodict['module']
+    wrapper.__dict__.update(infodict['dict'])
+    wrapper.func_defaults = infodict['defaults']
+    return wrapper
+
+# the real meat is here
+def _decorator(caller, func):
+    infodict = getinfo(func)
+    argnames = infodict['argnames']
+    assert not ('_call_' in argnames or '_func_' in argnames), \
+           'You cannot use _call_ or _func_ as argument names!'
+    src = "lambda %(signature)s: _call_(_func_, %(signature)s)" % infodict
+    dec_func = eval(src, dict(_func_=func, _call_=caller))
+    return update_wrapper(dec_func, func)
+
+def decorator(caller, func=None):
+    """
+    General purpose decorator factory: takes a caller function as
+    input and returns a decorator with the same attributes.
+    A caller function is any function like this::
+
+     def caller(func, *args, **kw):
+         # do something
+         return func(*args, **kw)
+
+    Here is an example of usage:
+
+    >>> @decorator
+    ... def chatty(f, *args, **kw):
+    ...     print "Calling %r" % f.__name__
+    ...     return f(*args, **kw)
+
+    >>> chatty.__name__
+    'chatty'
+
+    >>> @chatty
+    ... def f(): pass
+    ...
+    >>> f()
+    Calling 'f'
+
+    For sake of convenience, the decorator factory can also be called with
+    two arguments. In this casem ``decorator(caller, func)`` is just a
+    shortcut for ``decorator(caller)(func)``.
+    """
+    if func is None: # return a decorator function
+        return update_wrapper(lambda f : _decorator(caller, f), caller)
+    else: # return a decorated function
+        return _decorator(caller, func)
+
+if __name__ == "__main__":
+    import doctest; doctest.testmod()
diff --git a/src/mock/trace_decorator.py b/src/mock/trace_decorator.py
new file mode 100755
index 0000000..9e9b691
--- /dev/null
+++ b/src/mock/trace_decorator.py
@@ -0,0 +1,33 @@
+# vim:expandtab:autoindent:tabstop=4:shiftwidth=4:filetype=python:textwidth=0:
+
+import types
+from decorator import decorator
+
+import logging
+log = logging.getLogger("function_tracing")
+
+#@decorator
+@decorator
+def trace(f, *args, **kw):
+    log.debug("ENTER: %s(%s, %s)\n" % (f.func_name, args, kw))
+    try:
+        result = "Bad exception raised: Exception was not a derived class of 'Exception'"
+        try:
+            result = f(*args, **kw)
+        except Exception, e:
+            result = "EXCEPTION RAISED"
+            log.debug( "EXCEPTION: %s\n" % e, exc_info=1)
+            raise
+    finally:
+        log.debug( "LEAVE %s --> %s\n\n" % (f.func_name, result))
+
+    return result
+
+# helper function so we can use back-compat format but not be ugly
+def decorateAllFunctions(module):
+    methods = [ method for method in dir(module)
+            if isinstance(getattr(module, method), types.FunctionType)
+            ]
+    for i in methods:
+        setattr(module, i, trace(getattr(module,i)))
+