1#!/usr/bin/env python
2#
3# Copyright 2008 Google Inc.  All Rights Reserved.
4#
5# Licensed under the Apache License, Version 2.0 (the "License");
6# you may not use this file except in compliance with the License.
7# You may obtain a copy of the License at
8#
9#      http://www.apache.org/licenses/LICENSE-2.0
10#
11# Unless required by applicable law or agreed to in writing, software
12# distributed under the License is distributed on an "AS IS" BASIS,
13# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14# See the License for the specific language governing permissions and
15# limitations under the License.
16
17"""Generate Google Mock classes from base classes.
18
19This program will read in a C++ source file and output the Google Mock
20classes for the specified classes.  If no class is specified, all
21classes in the source file are emitted.
22
23Usage:
24  gmock_class.py header-file.h [ClassName]...
25
26Output is sent to stdout.
27"""
28
29__author__ = 'nnorwitz@google.com (Neal Norwitz)'
30
31
32import os
33import re
34import sys
35
36from cpp import ast
37from cpp import utils
38
39# Preserve compatibility with Python 2.3.
40try:
41  _dummy = set
42except NameError:
43  import sets
44  set = sets.Set
45
46_VERSION = (1, 0, 1)  # The version of this script.
47# How many spaces to indent.  Can set me with the INDENT environment variable.
48_INDENT = 2
49
50
51def _GenerateMethods(output_lines, source, class_node):
52  function_type = (ast.FUNCTION_VIRTUAL | ast.FUNCTION_PURE_VIRTUAL |
53                   ast.FUNCTION_OVERRIDE)
54  ctor_or_dtor = ast.FUNCTION_CTOR | ast.FUNCTION_DTOR
55  indent = ' ' * _INDENT
56
57  for node in class_node.body:
58    # We only care about virtual functions.
59    if (isinstance(node, ast.Function) and
60        node.modifiers & function_type and
61        not node.modifiers & ctor_or_dtor):
62      # Pick out all the elements we need from the original function.
63      const = ''
64      if node.modifiers & ast.FUNCTION_CONST:
65        const = 'CONST_'
66      return_type = 'void'
67      if node.return_type:
68        # Add modifiers like 'const'.
69        modifiers = ''
70        if node.return_type.modifiers:
71          modifiers = ' '.join(node.return_type.modifiers) + ' '
72        return_type = modifiers + node.return_type.name
73        template_args = [arg.name for arg in node.return_type.templated_types]
74        if template_args:
75          return_type += '<' + ', '.join(template_args) + '>'
76          if len(template_args) > 1:
77            for line in [
78                '// The following line won\'t really compile, as the return',
79                '// type has multiple template arguments.  To fix it, use a',
80                '// typedef for the return type.']:
81              output_lines.append(indent + line)
82        if node.return_type.pointer:
83          return_type += '*'
84        if node.return_type.reference:
85          return_type += '&'
86        num_parameters = len(node.parameters)
87        if len(node.parameters) == 1:
88          first_param = node.parameters[0]
89          if source[first_param.start:first_param.end].strip() == 'void':
90            # We must treat T(void) as a function with no parameters.
91            num_parameters = 0
92      tmpl = ''
93      if class_node.templated_types:
94        tmpl = '_T'
95      mock_method_macro = 'MOCK_%sMETHOD%d%s' % (const, num_parameters, tmpl)
96
97      args = ''
98      if node.parameters:
99        # Due to the parser limitations, it is impossible to keep comments
100        # while stripping the default parameters.  When defaults are
101        # present, we choose to strip them and comments (and produce
102        # compilable code).
103        # TODO(nnorwitz@google.com): Investigate whether it is possible to
104        # preserve parameter name when reconstructing parameter text from
105        # the AST.
106        if len([param for param in node.parameters if param.default]) > 0:
107          args = ', '.join(param.type.name for param in node.parameters)
108        else:
109          # Get the full text of the parameters from the start
110          # of the first parameter to the end of the last parameter.
111          start = node.parameters[0].start
112          end = node.parameters[-1].end
113          # Remove // comments.
114          args_strings = re.sub(r'//.*', '', source[start:end])
115          # Condense multiple spaces and eliminate newlines putting the
116          # parameters together on a single line.  Ensure there is a
117          # space in an argument which is split by a newline without
118          # intervening whitespace, e.g.: int\nBar
119          args = re.sub('  +', ' ', args_strings.replace('\n', ' '))
120
121      # Create the mock method definition.
122      output_lines.extend(['%s%s(%s,' % (indent, mock_method_macro, node.name),
123                           '%s%s(%s));' % (indent*3, return_type, args)])
124
125
126def _GenerateMocks(filename, source, ast_list, desired_class_names):
127  processed_class_names = set()
128  lines = []
129  for node in ast_list:
130    if (isinstance(node, ast.Class) and node.body and
131        # desired_class_names being None means that all classes are selected.
132        (not desired_class_names or node.name in desired_class_names)):
133      class_name = node.name
134      parent_name = class_name
135      processed_class_names.add(class_name)
136      class_node = node
137      # Add namespace before the class.
138      if class_node.namespace:
139        lines.extend(['namespace %s {' % n for n in class_node.namespace])  # }
140        lines.append('')
141
142      # Add template args for templated classes.
143      if class_node.templated_types:
144        # TODO(paulchang): The AST doesn't preserve template argument order,
145        # so we have to make up names here.
146        # TODO(paulchang): Handle non-type template arguments (e.g.
147        # template<typename T, int N>).
148        template_arg_count = len(class_node.templated_types.keys())
149        template_args = ['T%d' % n for n in range(template_arg_count)]
150        template_decls = ['typename ' + arg for arg in template_args]
151        lines.append('template <' + ', '.join(template_decls) + '>')
152        parent_name += '<' + ', '.join(template_args) + '>'
153
154      # Add the class prolog.
155      lines.append('class Mock%s : public %s {'  # }
156                   % (class_name, parent_name))
157      lines.append('%spublic:' % (' ' * (_INDENT // 2)))
158
159      # Add all the methods.
160      _GenerateMethods(lines, source, class_node)
161
162      # Close the class.
163      if lines:
164        # If there are no virtual methods, no need for a public label.
165        if len(lines) == 2:
166          del lines[-1]
167
168        # Only close the class if there really is a class.
169        lines.append('};')
170        lines.append('')  # Add an extra newline.
171
172      # Close the namespace.
173      if class_node.namespace:
174        for i in range(len(class_node.namespace)-1, -1, -1):
175          lines.append('}  // namespace %s' % class_node.namespace[i])
176        lines.append('')  # Add an extra newline.
177
178  if desired_class_names:
179    missing_class_name_list = list(desired_class_names - processed_class_names)
180    if missing_class_name_list:
181      missing_class_name_list.sort()
182      sys.stderr.write('Class(es) not found in %s: %s\n' %
183                       (filename, ', '.join(missing_class_name_list)))
184  elif not processed_class_names:
185    sys.stderr.write('No class found in %s\n' % filename)
186
187  return lines
188
189
190def main(argv=sys.argv):
191  if len(argv) < 2:
192    sys.stderr.write('Google Mock Class Generator v%s\n\n' %
193                     '.'.join(map(str, _VERSION)))
194    sys.stderr.write(__doc__)
195    return 1
196
197  global _INDENT
198  try:
199    _INDENT = int(os.environ['INDENT'])
200  except KeyError:
201    pass
202  except:
203    sys.stderr.write('Unable to use indent of %s\n' % os.environ.get('INDENT'))
204
205  filename = argv[1]
206  desired_class_names = None  # None means all classes in the source file.
207  if len(argv) >= 3:
208    desired_class_names = set(argv[2:])
209  source = utils.ReadFile(filename)
210  if source is None:
211    return 1
212
213  builder = ast.BuilderFromSource(source, filename)
214  try:
215    entire_ast = filter(None, builder.Generate())
216  except KeyboardInterrupt:
217    return
218  except:
219    # An error message was already printed since we couldn't parse.
220    sys.exit(1)
221  else:
222    lines = _GenerateMocks(filename, source, entire_ast, desired_class_names)
223    sys.stdout.write('\n'.join(lines))
224
225
226if __name__ == '__main__':
227  main(sys.argv)
228