new_contents: # Copyright (c) 2016 Ben Noordhuis <info@bnoordhuis.nl>. All rights reserved.
  # Use of this source code is governed by a BSD-style license that can be
  # found in the LICENSE file.
  
  import gyp.common
  import gyp.xcode_emulation
  import json
  import os
  
  generator_additional_non_configuration_keys = []
  generator_additional_path_sections = []
  generator_extra_sources_for_rules = []
  generator_filelist_paths = None
  generator_supports_multiple_toolsets = True
  generator_wants_sorted_dependencies = False
  
  # Lifted from make.py.  The actual values don't matter much.
  generator_default_variables = {
    'CONFIGURATION_NAME': '$(BUILDTYPE)',
    'EXECUTABLE_PREFIX': '',
    'EXECUTABLE_SUFFIX': '',
    'INTERMEDIATE_DIR': '$(obj).$(TOOLSET)/$(TARGET)/geni',
    'PRODUCT_DIR': '$(builddir)',
    'RULE_INPUT_DIRNAME': '%(INPUT_DIRNAME)s',
    'RULE_INPUT_EXT': '$(suffix $<)',
    'RULE_INPUT_NAME': '$(notdir $<)',
    'RULE_INPUT_PATH': '$(abspath $<)',
    'RULE_INPUT_ROOT': '%(INPUT_ROOT)s',
    'SHARED_INTERMEDIATE_DIR': '$(obj)/gen',
    'SHARED_LIB_PREFIX': 'lib',
    'STATIC_LIB_PREFIX': 'lib',
    'STATIC_LIB_SUFFIX': '.a',
  }
  
  
  def IsMac(params):
    return 'mac' == gyp.common.GetFlavor(params)
  
  
  def CalculateVariables(default_variables, params):
    default_variables.setdefault('OS', gyp.common.GetFlavor(params))
  
  
  def AddCommandsForTarget(cwd, target, params, per_config_commands):
    output_dir = params['generator_flags']['output_dir']
    for configuration_name, configuration in target['configurations'].iteritems():
      builddir_name = os.path.join(output_dir, configuration_name)
  
      if IsMac(params):
        xcode_settings = gyp.xcode_emulation.XcodeSettings(target)
        cflags = xcode_settings.GetCflags(configuration_name)
        cflags_c = xcode_settings.GetCflagsC(configuration_name)
        cflags_cc = xcode_settings.GetCflagsCC(configuration_name)
      else:
        cflags = configuration.get('cflags', [])
        cflags_c = configuration.get('cflags_c', [])
        cflags_cc = configuration.get('cflags_cc', [])
  
      cflags_c = cflags + cflags_c
      cflags_cc = cflags + cflags_cc
  
      defines = configuration.get('defines', [])
      defines = ['-D' + s for s in defines]
  
      # TODO(bnoordhuis) Handle generated source files.
      sources = target.get('sources', [])
      sources = [s for s in sources if s.endswith('.c') or s.endswith('.cc')]
  
      def resolve(filename):
        return os.path.abspath(os.path.join(cwd, filename))
  
      # TODO(bnoordhuis) Handle generated header files.
      include_dirs = configuration.get('include_dirs', [])
      include_dirs = [s for s in include_dirs if not s.startswith('$(obj)')]
      includes = ['-I' + resolve(s) for s in include_dirs]
  
      defines = gyp.common.EncodePOSIXShellList(defines)
      includes = gyp.common.EncodePOSIXShellList(includes)
      cflags_c = gyp.common.EncodePOSIXShellList(cflags_c)
      cflags_cc = gyp.common.EncodePOSIXShellList(cflags_cc)
  
      commands = per_config_commands.setdefault(configuration_name, [])
      for source in sources:
        file = resolve(source)
        isc = source.endswith('.c')
        cc = 'cc' if isc else 'c++'
        cflags = cflags_c if isc else cflags_cc
        command = ' '.join((cc, defines, includes, cflags,
                            '-c', gyp.common.EncodePOSIXShellArgument(file)))
        commands.append(dict(command=command, directory=output_dir, file=file))
  
  
  def GenerateOutput(target_list, target_dicts, data, params):
    per_config_commands = {}
    for qualified_target, target in target_dicts.iteritems():
      build_file, target_name, toolset = (
          gyp.common.ParseQualifiedTarget(qualified_target))
      if IsMac(params):
        settings = data[build_file]
        gyp.xcode_emulation.MergeGlobalXcodeSettingsToSpec(settings, target)
      cwd = os.path.dirname(build_file)
      AddCommandsForTarget(cwd, target, params, per_config_commands)
  
    output_dir = params['generator_flags']['output_dir']
    for configuration_name, commands in per_config_commands.iteritems():
      filename = os.path.join(output_dir,
                              configuration_name,
                              'compile_commands.json')
      gyp.common.EnsureDirExists(filename)
      fp = open(filename, 'w')
      json.dump(commands, fp=fp, indent=0, check_circular=False)
  
  
  def PerformBuild(data, configurations, params):
    pass
  
subject: add compile_commands.json gyp generator