Refactor gmock_mutant.h

testing/generate_gmock_mutant.py

-#!/usr/bin/env python
-# Copyright (c) 2012 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-import string
-import sys
-
-HEADER = """\
-// Copyright (c) 2013 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// This file automatically generated by testing/generate_gmock_mutant.py.
-// DO NOT EDIT.
-
-#ifndef TESTING_GMOCK_MUTANT_H_
-#define TESTING_GMOCK_MUTANT_H_
-
-// The intention of this file is to make possible using GMock actions in
-// all of its syntactic beauty. Classes and helper functions can be used as
-// more generic variants of Task and Callback classes (see base/task.h)
-// Mutant supports both pre-bound arguments (like Task) and call-time
-// arguments (like Callback) - hence the name. :-)
-//
-// DispatchToMethod/Function supports two sets of arguments: pre-bound (P) and
-// call-time (C). The arguments as well as the return type are templatized.
-// DispatchToMethod/Function will also try to call the selected method or
-// function even if provided pre-bound arguments does not match exactly with
-// the function signature hence the X1, X2 ... XN parameters in CreateFunctor.
-// DispatchToMethod will try to invoke method that may not belong to the
-// object's class itself but to the object's class base class.
-//
-// Additionally you can bind the object at calltime by binding a pointer to
-// pointer to the object at creation time - before including this file you
-// have to #define GMOCK_MUTANT_INCLUDE_LATE_OBJECT_BINDING.
-//
-// TODO(stoyan): It's yet not clear to me should we use T& and T&* instead
-// of T* and T** when we invoke CreateFunctor to match the EXPECT_CALL style.
-//
-//
-// Sample usage with gMock:
-//
-// struct Mock : public ObjectDelegate {
-//   MOCK_METHOD2(string, OnRequest(int n, const string& request));
-//   MOCK_METHOD1(void, OnQuit(int exit_code));
-//   MOCK_METHOD2(void, LogMessage(int level, const string& message));
-//
-//   string HandleFlowers(const string& reply, int n, const string& request) {
-//     string result = SStringPrintf("In request of %d %s ", n, request);
-//     for (int i = 0; i < n; ++i) result.append(reply)
-//     return result;
-//   }
-//
-//   void DoLogMessage(int level, const string& message) {
-//   }
-//
-//   void QuitMessageLoop(int seconds) {
-//     base::MessageLoop* loop = base::MessageLoop::current();
-//     loop->PostDelayedTask(FROM_HERE,
-//                           base::MessageLoop::QuitWhenIdleClosure(),
-//                           1000 * seconds);
-//   }
-// };
-//
-// Mock mock;
-// // Will invoke mock.HandleFlowers("orchids", n, request)
-// // "orchids" is a pre-bound argument, and <n> and <request> are call-time
-// // arguments - they are not known until the OnRequest mock is invoked.
-// EXPECT_CALL(mock, OnRequest(Ge(5), base::StartsWith("flower"))
-//   .Times(1)
-//   .WillOnce(Invoke(CreateFunctor(&mock, &Mock::HandleFlowers,
-//       string("orchids"))));
-//
-//
-// // No pre-bound arguments, two call-time arguments passed
-// // directly to DoLogMessage
-// EXPECT_CALL(mock, OnLogMessage(_, _))
-//   .Times(AnyNumber())
-//   .WillAlways(Invoke(CreateFunctor, &mock, &Mock::DoLogMessage));
-//
-//
-// // In this case we have a single pre-bound argument - 3. We ignore
-// // all of the arguments of OnQuit.
-// EXCEPT_CALL(mock, OnQuit(_))
-//   .Times(1)
-//   .WillOnce(InvokeWithoutArgs(CreateFunctor(
-//       &mock, &Mock::QuitMessageLoop, 3)));
-//
-// MessageLoop loop;
-// loop.Run();
-//
-//
-//  // Here is another example of how we can set an action that invokes
-//  // method of an object that is not yet created.
-// struct Mock : public ObjectDelegate {
-//   MOCK_METHOD1(void, DemiurgeCreated(Demiurge*));
-//   MOCK_METHOD2(void, OnRequest(int count, const string&));
-//
-//   void StoreDemiurge(Demiurge* w) {
-//     demiurge_ = w;
-//   }
-//
-//   Demiurge* demiurge;
-// }
-//
-// EXPECT_CALL(mock, DemiurgeCreated(_)).Times(1)
-//    .WillOnce(Invoke(CreateFunctor(&mock, &Mock::StoreDemiurge)));
-//
-// EXPECT_CALL(mock, OnRequest(_, StrEq("Moby Dick")))
-//    .Times(AnyNumber())
-//    .WillAlways(WithArgs<0>(Invoke(
-//        CreateFunctor(&mock->demiurge_, &Demiurge::DecreaseMonsters))));
-//
-
-#include "base/memory/linked_ptr.h"
-#include "base/tuple.h"
-
-namespace testing {"""
-
-MUTANT = """\
-
-// Interface that is exposed to the consumer, that does the actual calling
-// of the method.
-template <typename R, typename Params>
-class MutantRunner {
- public:
-  virtual R RunWithParams(const Params& params) = 0;
-  virtual ~MutantRunner() {}
-};
-
-// Mutant holds pre-bound arguments (like Task). Like Callback
-// allows call-time arguments. You bind a pointer to the object
-// at creation time.
-template <typename R, typename T, typename Method,
-          typename PreBound, typename Params>
-class Mutant : public MutantRunner<R, Params> {
- public:
-  Mutant(T* obj, Method method, const PreBound& pb)
-      : obj_(obj), method_(method), pb_(pb) {
-  }
-
-  // MutantRunner implementation
-  virtual R RunWithParams(const Params& params) {
-    return DispatchToMethod<R>(this->obj_, this->method_, pb_, params);
-  }
-
-  T* obj_;
-  Method method_;
-  PreBound pb_;
-};
-
-template <typename R, typename Function, typename PreBound, typename Params>
-class MutantFunction : public MutantRunner<R, Params> {
- public:
-  MutantFunction(Function function, const PreBound& pb)
-      : function_(function), pb_(pb) {
-  }
-
-  // MutantRunner implementation
-  virtual R RunWithParams(const Params& params) {
-    return DispatchToFunction<R>(function_, pb_, params);
-  }
-
-  Function function_;
-  PreBound pb_;
-};
-
-#ifdef GMOCK_MUTANT_INCLUDE_LATE_OBJECT_BINDING
-// MutantLateBind is like Mutant, but you bind a pointer to a pointer
-// to the object. This way you can create actions for an object
-// that is not yet created (has only storage for a pointer to it).
-template <typename R, typename T, typename Method,
-          typename PreBound, typename Params>
-class MutantLateObjectBind : public MutantRunner<R, Params> {
- public:
-  MutantLateObjectBind(T** obj, Method method, const PreBound& pb)
-      : obj_(obj), method_(method), pb_(pb) {
-  }
-
-  // MutantRunner implementation.
-  virtual R RunWithParams(const Params& params) {
-    EXPECT_THAT(*this->obj_, testing::NotNull());
-    if (NULL == *this->obj_)
-      return R();
-    return DispatchToMethod<R>( *this->obj_, this->method_, pb_, params);
-  }
-
-  T** obj_;
-  Method method_;
-  PreBound pb_;
-};
-#endif
-
-// Simple MutantRunner<> wrapper acting as a functor.
-// Redirects operator() to MutantRunner<Params>::Run()
-template <typename R, typename Params>
-struct MutantFunctor {
-  explicit MutantFunctor(MutantRunner<R, Params>*  cb) : impl_(cb) {
-  }
-
-  ~MutantFunctor() {
-  }
-
-  inline R operator()() {
-    return impl_->RunWithParams(base::Tuple<>());
-  }
-
-  template <typename Arg1>
-  inline R operator()(const Arg1& a) {
-    return impl_->RunWithParams(Params(a));
-  }
-
-  template <typename Arg1, typename Arg2>
-  inline R operator()(const Arg1& a, const Arg2& b) {
-    return impl_->RunWithParams(Params(a, b));
-  }
-
-  template <typename Arg1, typename Arg2, typename Arg3>
-  inline R operator()(const Arg1& a, const Arg2& b, const Arg3& c) {
-    return impl_->RunWithParams(Params(a, b, c));
-  }
-
-  template <typename Arg1, typename Arg2, typename Arg3, typename Arg4>
-  inline R operator()(const Arg1& a, const Arg2& b, const Arg3& c,
-                         const Arg4& d) {
-    return impl_->RunWithParams(Params(a, b, c, d));
-  }
-
- private:
-  // We need copy constructor since MutantFunctor is copied few times
-  // inside GMock machinery, hence no DISALLOW_EVIL_CONTRUCTORS
-  MutantFunctor();
-  linked_ptr<MutantRunner<R, Params> > impl_;
-};
-"""
-
-FOOTER = """\
-}  // namespace testing
-
-#endif  // TESTING_GMOCK_MUTANT_H_"""
-
-# Templates for DispatchToMethod/DispatchToFunction functions.
-# template_params - typename P1, typename P2.. typename C1..
-# prebound - Tuple<P1, .. PN>
-# calltime - Tuple<C1, .. CN>
-# args - p.a, p.b.., c.a, c.b..
-DISPATCH_TO_METHOD_TEMPLATE = """\
-template <typename R, typename T, typename Method, %(template_params)s>
-inline R DispatchToMethod(T* obj, Method method,
-                          const %(prebound)s& p,
-                          const %(calltime)s& c) {
-  return (obj->*method)(%(args)s);
-}
-"""
-
-DISPATCH_TO_FUNCTION_TEMPLATE = """\
-template <typename R, typename Function, %(template_params)s>
-inline R DispatchToFunction(Function function,
-                            const %(prebound)s& p,
-                            const %(calltime)s& c) {
-  return (*function)(%(args)s);
-}
-"""
-
-# Templates for CreateFunctor functions.
-# template_params - typename P1, typename P2.. typename C1.. typename X1..
-# prebound - Tuple<P1, .. PN>
-# calltime - Tuple<A1, .. AN>
-# params - X1,.. , A1, ..
-# args - const P1& p1 ..
-# call_args - p1, p2, p3..
-CREATE_METHOD_FUNCTOR_TEMPLATE = """\
-template <typename R, typename T, typename U, %(template_params)s>
-inline MutantFunctor<R, %(calltime)s>
-CreateFunctor(T* obj, R (U::*method)(%(params)s), %(args)s) {
-  MutantRunner<R, %(calltime)s>* t =
-      new Mutant<R, T, R (U::*)(%(params)s),
-                 %(prebound)s, %(calltime)s>
-          (obj, method, base::MakeTuple(%(call_args)s));
-  return MutantFunctor<R, %(calltime)s>(t);
-}
-"""
-
-CREATE_FUNCTION_FUNCTOR_TEMPLATE = """\
-template <typename R, %(template_params)s>
-inline MutantFunctor<R, %(calltime)s>
-CreateFunctor(R (*function)(%(params)s), %(args)s) {
-  MutantRunner<R, %(calltime)s>* t =
-      new MutantFunction<R, R (*)(%(params)s),
-                         %(prebound)s, %(calltime)s>
-          (function, base::MakeTuple(%(call_args)s));
-  return MutantFunctor<R, %(calltime)s>(t);
-}
-"""
-
-def SplitLine(line, width):
-  """Splits a single line at comma, at most |width| characters long."""
-  if len(line) <= width:
-    return (line, None)
-  n = 1 + line[:width].rfind(",")
-  if n == 0:  # If comma cannot be found give up and return the entire line.
-    return (line, None)
-  # Assume there is a space after the comma
-  assert line[n] == " "
-  return (line[:n], line[n + 1:])
-
-
-def Wrap(s, width, subsequent_offset):
-  """Wraps a single line |s| at commas so every line is at most |width|
-     characters long.
-  """
-  w = []
-  spaces = " " * subsequent_offset
-  while s:
-    (f, s) = SplitLine(s, width)
-    w.append(f)
-    if s:
-      s = spaces  + s
-  return "\n".join(w)
-
-
-def Clean(s):
-  """Cleans artifacts from generated C++ code.
-
-  Our simple string formatting/concatenation may introduce extra commas.
-  """
-  s = s.replace(", >", ">")
-  s = s.replace(", )", ")")
-  return s
-
-
-def ExpandPattern(pattern, it):
-  """Return list of expanded pattern strings.
-
-  Each string is created by replacing all '%' in |pattern| with element of |it|.
-  """
-  return [pattern.replace("%", x) for x in it]
-
-
-def Gen(pattern, n, start):
-  """Expands pattern replacing '%' with sequential integers starting with start.
-
-  Expanded patterns will be joined with comma separator.
-  Gen("X%", 3, 1) will return "X1, X2, X3".
-  """
-  it = string.hexdigits[start:n + start]
-  return ", ".join(ExpandPattern(pattern, it))
-
-
-def Merge(a):
-  return ", ".join(filter(len, a))
-
-
-def GenTuple(pattern, n):
-  return Clean("base::Tuple<%s>" % (Gen(pattern, n, 1)))
-
-
-def FixCode(s):
-  lines = Clean(s).splitlines()
-  # Wrap sometimes very long 1st line to be inside the "template <"
-  lines[0] = Wrap(lines[0], 80, 10)
-
-  # Wrap all subsequent lines to 6 spaces arbitrarily. This is a 2-space line
-  # indent, plus a 4 space continuation indent.
-  for line in xrange(1, len(lines)):
-    lines[line] = Wrap(lines[line], 80, 6)
-  return "\n".join(lines)
-
-
-def GenerateDispatch(prebound, calltime):
-  print "\n// %d - %d" % (prebound, calltime)
-  args = {
-      "template_params": Merge([Gen("typename P%", prebound, 1),
-                                Gen("typename C%", calltime, 1)]),
-      "prebound": GenTuple("P%", prebound),
-      "calltime": GenTuple("C%", calltime),
-      "args": Merge([Gen("base::get<%>(p)", prebound, 0),
-                     Gen("base::get<%>(c)", calltime, 0)]),
-  }
-
-  print FixCode(DISPATCH_TO_METHOD_TEMPLATE % args)
-  print FixCode(DISPATCH_TO_FUNCTION_TEMPLATE % args)
-
-
-def GenerateCreateFunctor(prebound, calltime):
-  print "// %d - %d" % (prebound, calltime)
-  args = {
-      "calltime": GenTuple("A%", calltime),
-      "prebound": GenTuple("P%", prebound),
-      "params": Merge([Gen("X%", prebound, 1), Gen("A%", calltime, 1)]),
-      "args": Gen("const P%& p%", prebound, 1),
-      "call_args": Gen("p%", prebound, 1),
-      "template_params": Merge([Gen("typename P%", prebound, 1),
-                                Gen("typename A%", calltime, 1),
-                                Gen("typename X%", prebound, 1)])
-  }
-
-  mutant = FixCode(CREATE_METHOD_FUNCTOR_TEMPLATE % args)
-  print mutant
-
-  # Slightly different version for free function call.
-  print "\n", FixCode(CREATE_FUNCTION_FUNCTOR_TEMPLATE % args)
-
-  # Functor with pointer to a pointer of the object.
-  print "\n#ifdef GMOCK_MUTANT_INCLUDE_LATE_OBJECT_BINDING"
-  mutant2 = mutant.replace("CreateFunctor(T* obj,", "CreateFunctor(T** obj,")
-  mutant2 = mutant2.replace("new Mutant", "new MutantLateObjectBind")
-  mutant2 = mutant2.replace(" " * 17 + "Tuple", " " * 31 + "Tuple")
-  print mutant2
-  print "#endif  // GMOCK_MUTANT_INCLUDE_LATE_OBJECT_BINDING\n"
-
-  # OS_WIN specific. Same functors but with stdcall calling conventions.
-  # These are not for WIN64 (x86_64) because there is only one calling
-  # convention in WIN64.
-  # Functor for method with __stdcall calling conventions.
-  print "#if defined (OS_WIN) && !defined (ARCH_CPU_X86_64)"
-  stdcall_method = CREATE_METHOD_FUNCTOR_TEMPLATE
-  stdcall_method = stdcall_method.replace("U::", "__stdcall U::")
-  stdcall_method = FixCode(stdcall_method % args)
-  print stdcall_method
-  # Functor for free function with __stdcall calling conventions.
-  stdcall_function = CREATE_FUNCTION_FUNCTOR_TEMPLATE
-  stdcall_function = stdcall_function.replace("R (*", "R (__stdcall *")
-  print "\n", FixCode(stdcall_function % args)
-
-  print "#ifdef GMOCK_MUTANT_INCLUDE_LATE_OBJECT_BINDING"
-  stdcall2 = stdcall_method
-  stdcall2 = stdcall2.replace("CreateFunctor(T* obj,", "CreateFunctor(T** obj,")
-  stdcall2 = stdcall2.replace("new Mutant", "new MutantLateObjectBind")
-  stdcall2 = stdcall2.replace(" " * 17 + "Tuple", " " * 31 + "Tuple")
-  print stdcall2
-  print "#endif  // GMOCK_MUTANT_INCLUDE_LATE_OBJECT_BINDING"
-  print "#endif  // defined (OS_WIN) && !defined (ARCH_CPU_X86_64)\n"
-
-
-def main():
-  print HEADER
-  for prebound in xrange(0, 6 + 1):
-    for args in xrange(0, 6 + 1):
-      GenerateDispatch(prebound, args)
-  print MUTANT
-  for prebound in xrange(0, 6 + 1):
-    for args in xrange(0, 6 + 1):
-      GenerateCreateFunctor(prebound, args)
-  print FOOTER
-  return 0
-
-
-if __name__ == "__main__":
-  sys.exit(main())