Get rid of System classes for backend generators.

lib/html/scripts/dartdomgenerator.py

 #!/usr/bin/python
 # Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 """This is the entry point to create Dart APIs from the IDL database."""
 
 import dartgenerator
 import database
 import logging.config
 import multiemitter
 import optparse
 import os
 import shutil
 import subprocess
 import sys
 from generator import TypeRegistry
 from htmlrenamer import HtmlRenamer
 from systembase import GeneratorOptions
 from systemdart2js import Dart2JSSystem
 from systemhtml import DartLibraryEmitter, HtmlInterfacesSystem,\
-                       HtmlDart2JSSystem
+                       Dart2JSGeneratorBackend
 from systeminterface import InterfacesSystem
-from systemnative import CPPLibraryEmitter, NativeImplementationSystem
+from systemnative import CPPLibraryEmitter, DartiumGeneratorBackend
 from templateloader import TemplateLoader
 
 _logger = logging.getLogger('dartdomgenerator')
 
 _webkit_renames = {
     # W3C -> WebKit name conversion
     # TODO(vsm): Maybe Store these renames in the IDLs.
     'ApplicationCache': 'DOMApplicationCache',
     'BarProp': 'BarInfo',
     'DedicatedWorkerGlobalScope': 'DedicatedWorkerContext',
@@ skipping 27 matching lines @@
                              exclude_displaced = ['WebKit'],
                              exclude_suppressed = ['WebKit', 'Dart'])
   generator.RenameTypes(webkit_database, _webkit_renames, True)
   generator.FixEventTargets(webkit_database)
   generator.AddMissingArguments(webkit_database)
 
   emitters = multiemitter.MultiEmitter()
   renamer = HtmlRenamer(webkit_database)
   type_registry = TypeRegistry(webkit_database, renamer)
 
   def RunGenerator(dart_library_template, dart_output_dir, dart_library_path,

[Anton Muhin, 2012/09/26 14:20:36]

overall logic becomes rather complicated, so, sorry, couple of comments in
attempt to make understanding the code below easier

-               backend):
+                   create_generator_backend):

[Anton Muhin, 2012/09/26 14:20:36]

I'd rather name it generator_backend_factory.

[Anton Muhin, 2012/09/26 14:20:36]

generator backend sounds somewhat too much, can it be just generator?  Overall
it looks weird to see class FooGeneratorBackend extending BaseGenerator,
FooBackendGenerator or even FooGenerator looks ways more readable.

[podivilov, 2012/09/26 15:02:04]

Done.

[podivilov, 2012/09/26 15:02:04]

Renamed to FooBackend. Backends should not extend BaseGenerator (subject to a
separate cl).

     template_loader = TemplateLoader(

[Anton Muhin, 2012/09/26 14:20:36]

cannot we lift template_loader creation out of this function?

[podivilov, 2012/09/26 15:02:04]

Done.

         template_dir, ['html/interface', 'html/impl', 'html', ''], {})
     options = GeneratorOptions(

[Anton Muhin, 2012/09/26 14:20:36]

cannot we lift options creation out of this function?

         template_loader, webkit_database, type_registry, renamer)
     dart_library_emitter = DartLibraryEmitter(
         emitters, dart_library_template, dart_output_dir)
-    html_system = HtmlInterfacesSystem(options, dart_library_emitter, backend)
+    html_system = HtmlInterfacesSystem(
+        options, dart_library_emitter, create_generator_backend)
     generator.Generate(
         webkit_database, html_system, common_database, _webkit_renames)
     dart_library_emitter.EmitLibrary(dart_library_path, auxiliary_dir)
 
   if dart2js_output_dir:
     template_loader = TemplateLoader(template_dir,
                                      ['html/dart2js', 'html/impl', 'html', ''],
                                      {'DARTIUM': False, 'DART2JS': True})
     backend_options = GeneratorOptions(
         template_loader, webkit_database, type_registry, renamer)
-    backend = HtmlDart2JSSystem(backend_options)
+    def create_generator_backend(interface):

[Anton Muhin, 2012/09/26 14:20:36]

that might be a perfect case for lambda, esp. if you agree to change names

[podivilov, 2012/09/26 15:02:04]

Done.

+      return Dart2JSGeneratorBackend(interface, backend_options)
 
     dart_library_template = template_loader.Load('html_dart2js.darttemplate')
     dart_output_dir = os.path.join(dart2js_output_dir, 'dart')
     dart_library_path = os.path.join(dart2js_output_dir, 'html_dart2js.dart')
 
-    RunGenerator(
-        dart_library_template, dart_output_dir, dart_library_path, backend)
+    RunGenerator(dart_library_template, dart_output_dir, dart_library_path,
+                 create_generator_backend)
 
   if dartium_output_dir:
     template_loader = TemplateLoader(template_dir,
                                      ['html/dartium', 'html/impl', ''],
                                      {'DARTIUM': True, 'DART2JS': False})
     backend_options = GeneratorOptions(
         template_loader, webkit_database, type_registry, renamer)
     cpp_output_dir = os.path.join(dartium_output_dir, 'cpp')
     cpp_library_emitter = CPPLibraryEmitter(emitters, cpp_output_dir)
-    backend = NativeImplementationSystem(backend_options, cpp_library_emitter)
+    def create_generator_backend(interface):
+      return DartiumGeneratorBackend(
+          interface, cpp_library_emitter, backend_options)
 
     dart_library_template = template_loader.Load('html_dartium.darttemplate')
     dart_output_dir = os.path.join(dartium_output_dir, 'dart')
     dart_library_path = os.path.join(dartium_output_dir, 'html_dartium.dart')
 
-    RunGenerator(
-        dart_library_template, dart_output_dir, dart_library_path, backend)
+    RunGenerator(dart_library_template, dart_output_dir, dart_library_path,
+                 create_generator_backend)
     cpp_library_emitter.EmitDerivedSources(
         template_loader.Load('cpp_derived_sources.template'),
         dartium_output_dir)
     cpp_library_emitter.EmitResolver(
         template_loader.Load('cpp_resolver.template'), dartium_output_dir)
 
   _logger.info('Flush...')
   emitters.Flush()
 
 def GenerateSingleFile(library_path, output_dir):
@@ skipping 42 matching lines @@
     _logger.info('Copy html_dart2js to dart2js/')
     GenerateSingleFile(os.path.join(dart2js_output_dir, 'html_dart2js.dart'),
                        '../dart2js')
   if 'htmldartium' in systems:
     _logger.info('Copy html_dartium to dartium/')
     GenerateSingleFile(os.path.join(dartium_output_dir, 'html_dartium.dart'),
                        '../dartium')
 
 if __name__ == '__main__':
   sys.exit(main())