Wrapperless dart:html generator

client/dom/scripts/generator.py

+#!/usr/bin/python
+# Copyright (c) 2012, 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 module provides shared functionality for systems to generate
+Dart APIs from the IDL database."""
+
+import re
+
+# IDL->Dart primitive types conversion.
+_idl_to_dart_type_conversions = {
+    'any': 'Object',
+    'any[]': 'List',
+    'custom': 'Dynamic',
+    'boolean': 'bool',
+    'DOMObject': 'Object',
+    'DOMString': 'String',
+    'DOMStringList': 'List<String>',
+    'DOMTimeStamp': 'int',
+    'Date': 'Date',
+    # Map to num to enable callers to pass in Dart int, rational
+    # types.  Our implementations will need to convert these to
+    # doubles or floats as needed.
+    'double': 'num',
+    'float': 'num',
+    'int': 'int',
+    # Map to extra precision - int is a bignum in Dart.
+    'long': 'int',
+    'long long': 'int',
+    'object': 'Object',
+    # Map to extra precision - int is a bignum in Dart.
+    'short': 'int',
+    'string': 'String',
+    'void': 'void',
+    'Array': 'List',
+    'sequence': 'List',
+    # TODO(sra): Come up with some meaningful name so that where this appears in
+    # the documentation, the user is made aware that only a limited subset of
+    # serializable types are actually permitted.
+    'SerializedScriptValue': 'Dynamic',
+    # TODO(vsm): Automatically recognize types defined in src.
+    'TimeoutHandler': 'TimeoutHandler',
+    'RequestAnimationFrameCallback': 'RequestAnimationFrameCallback',
+
+    # TODO(sra): Flags is really a dictionary: {create:bool, exclusive:bool}
+    # http://dev.w3.org/2009/dap/file-system/file-dir-sys.html#the-flags-interface
+    'WebKitFlags': 'Object',
+    }
+
+_dart_to_idl_type_conversions = dict((v,k) for k, v in
+                                     _idl_to_dart_type_conversions.iteritems())
+
+#
+# Identifiers that are used in the IDL than need to be treated specially because
+# *some* JavaScript processors forbid them as properties.
+#
+_javascript_keywords = ['delete', 'continue']
+
+#
+# Interface version of the DOM needs to delegate typed array constructors to a
+# factory provider.
+#
+interface_factories = {
+    'Float32Array': '_TypedArrayFactoryProvider',
+    'Float64Array': '_TypedArrayFactoryProvider',
+    'Int8Array': '_TypedArrayFactoryProvider',
+    'Int16Array': '_TypedArrayFactoryProvider',
+    'Int32Array': '_TypedArrayFactoryProvider',
+    'Uint8Array': '_TypedArrayFactoryProvider',
+    'Uint16Array': '_TypedArrayFactoryProvider',
+    'Uint32Array': '_TypedArrayFactoryProvider',
+    'Uint8ClampedArray': '_TypedArrayFactoryProvider',
+}
+
+#
+# Custom methods that must be implemented by hand.
+#
+_custom_methods = set([
+    ('DOMWindow', 'setInterval'),
+    ('DOMWindow', 'setTimeout'),
+    ('WorkerContext', 'setInterval'),
+    ('WorkerContext', 'setTimeout'),
+    ('CanvasRenderingContext2D', 'setFillStyle'),
+    ('CanvasRenderingContext2D', 'setStrokeStyle'),
+    ('CanvasRenderingContext2D', 'setFillStyle'),
+    ])
+
+#
+# Custom getters that must be implemented by hand.
+#
+_custom_getters = set([
+    ('DOMWindow', 'localStorage'),
+    ])
+
+#
+# Custom native specs for the Frog dom.
+#
+_frog_dom_custom_native_specs = {
+    # Decorate the singleton Console object, if present (workers do not have a
+    # console).
+    'Console': "=(typeof console == 'undefined' ? {} : console)",
+
+    # DOMWindow aliased with global scope.
+    'DOMWindow': '@*DOMWindow',
+}
+
+#
+# Simple method substitution when one method had different names on different
+# browsers, but are otherwise identical.  The alternates are tried in order and
+# the first one defined is used.
+#
+# This can be probably be removed when Chrome renames initWebKitWheelEvent to
+# initWheelEvent.
+#
+_alternate_methods = {
+    ('WheelEvent', 'initWheelEvent'): ['initWebKitWheelEvent', 'initWheelEvent']
+}
+
+def ConvertPrimitiveType(type_name):
+  if type_name.startswith('unsigned '):
+    type_name = type_name[len('unsigned '):]
+
+  if type_name in _idl_to_dart_type_conversions:
+    # Primitive type conversion
+    return _idl_to_dart_type_conversions[type_name]
+  return None
+
+def IsPrimitiveType(type_name):
+  return (ConvertPrimitiveType(type_name) is not None or
+          type_name in _dart_to_idl_type_conversions)
+
+def MaybeListElementTypeName(type_name):
+  """Returns the List element type T from string of form "List<T>", or None."""
+  match = re.match(r'List<(\w*)>$', type_name)
+  if match:
+    return match.group(1)
+  return None
+
+def MaybeListElementType(interface):
+  """Returns the List element type T, or None in interface does not implement
+  List<T>.
+  """
+  for parent in interface.parents:
+    element_type = MaybeListElementTypeName(parent.type.id)
+    if element_type:
+      return element_type
+  return None
+
+def MaybeTypedArrayElementType(interface):
+  """Returns the typed array element type, or None in interface is not a
+  TypedArray.
+  """
+  # Typed arrays implement ArrayBufferView and List<T>.
+  for parent in interface.parents:
+    if  parent.type.id == 'ArrayBufferView':
+      return MaybeListElementType(interface)
+    if  parent.type.id == 'Uint8Array':
+      return 'int'
+  return None
+
+def MakeNativeSpec(javascript_binding_name):
+  if javascript_binding_name in _frog_dom_custom_native_specs:
+    return _frog_dom_custom_native_specs[javascript_binding_name]
+  else:
+    # Make the class 'hidden' so it is dynamically patched at runtime.  This
+    # is useful not only for browser compat, but to allow code that links
+    # against dart:dom to load in a worker isolate.
+    return '*' + javascript_binding_name
+
+
+def MatchSourceFilter(filter, thing):
+  if not filter:
+    return True
+  else:
+    return any(token in thing.annotations for token in filter)
+
+def AnalyzeOperation(interface, operations):
+  """Makes operation calling convention decision for a set of overloads.
+
+  Returns: An OperationInfo object.
+  """
+
+  # Zip together arguments from each overload by position, then convert
+  # to a dart argument.
+
+  # Given a list of overloaded arguments, choose a suitable name.
+  def OverloadedName(args):
+    return '_OR_'.join(sorted(set(arg.id for arg in args)))
+
+  # Given a list of overloaded arguments, choose a suitable type.
+  def OverloadedType(args):
+    typeIds = sorted(set(arg.type.id for arg in args))
+    if len(typeIds) == 1:
+      return typeIds[0]
+    else:
+      return TypeName(typeIds, interface)
+
+  # Given a list of overloaded arguments, render a dart argument.
+  def DartArg(args):
+    filtered = filter(None, args)
+    optional = any(not arg or arg.is_optional for arg in args)
+    type = OverloadedType(filtered)
+    name = OverloadedName(filtered)
+    if optional:
+      return (name, type, 'null')
+    else:
+      return (name, type, None)
+
+  args = map(lambda *args: DartArg(args),
+             *(op.arguments for op in operations))
+
+  info = OperationInfo()
+  info.overloads = operations
+  info.declared_name = operations[0].id
+  info.name = operations[0].ext_attrs.get('DartName', info.declared_name)
+  info.js_name = info.declared_name
+  info.type_name = operations[0].type.id   # TODO: widen.
+  info.arg_infos = args
+  return info
+
+def RecognizeCallback(interface):
+  """Returns the info for the callback method if the interface smells like a
+  callback.
+  """
+  if 'Callback' not in interface.ext_attrs: return None
+  handlers = [op for op in interface.operations if op.id == 'handleEvent']
+  if not handlers: return None
+  if not (handlers == interface.operations): return None
+  return AnalyzeOperation(interface, handlers)
+
+def IsDartListType(type):
+  return type == 'List' or type.startswith('List<')
+
+def IsDartCollectionType(type):
+  return IsDartListType(type)
+
+def FindMatchingAttribute(interface, attr1):
+  matches = [attr2 for attr2 in interface.attributes
+             if attr1.id == attr2.id
+             and attr1.is_fc_getter == attr2.is_fc_getter
+             and attr1.is_fc_setter == attr2.is_fc_setter]
+  if matches:
+    assert len(matches) == 1
+    return matches[0]
+  return None
+
+class OperationInfo(object):
+  """Holder for various derived information from a set of overloaded operations.
+
+  Attributes:
+    overloads: A list of IDL operation overloads with the same name.
+    name: A string, the simple name of the operation.
+    type_name: A string, the name of the return type of the operation.
+    arg_infos: A list of (name, type, default_value) tuples.
+        default_value is None for mandatory arguments.
+  """
+
+  def ParametersInterfaceDeclaration(self):
+    """Returns a formatted string declaring the parameters for the interface."""
+    return self._FormatArgs(self.arg_infos, True)
+
+  def ParametersImplementationDeclaration(self, rename_type=None):
+    """Returns a formatted string declaring the parameters for the
+    implementation.
+
+    Args:
+      rename_type: A function that allows the types to be renamed.
+    """
+    args = self.arg_infos
+    if rename_type:
+      args = [(name, rename_type(type), default)
+              for (name, type, default) in args]
+    return self._FormatArgs(args, False)
+
+  def ParametersAsArgumentList(self):
+    """Returns a formatted string declaring the parameters names as an argument
+    list.
+    """
+    return ', '.join(map(lambda arg_info: arg_info[0], self.arg_infos))
+
+  def _FormatArgs(self, args, is_interface):
+    def FormatArg(arg_info):
+      """Returns an argument declaration fragment for an argument info tuple."""
+      (name, type, default) = arg_info
+      if default:
+        return '%s %s = %s' % (type, name, default)
+      else:
+        return '%s %s' % (type, name)
+
+    required = []
+    optional = []
+    for (name, type, default) in args:
+      if default:
+        if is_interface:
+          optional.append((name, type, None))  # Default values illegal.
+        else:
+          optional.append((name, type, default))
+      else:
+        if optional:
+          raise Exception('Optional arguments cannot precede required ones: '
+                          + str(args))
+        required.append((name, type, None))
+    argtexts = map(FormatArg, required)
+    if optional:
+      argtexts.append('[' + ', '.join(map(FormatArg, optional)) + ']')
+    return ', '.join(argtexts)
+
+
+def AttributeOutputOrder(a, b):
+  """Canonical output ordering for attributes."""
+    # Getters before setters:
+  if a.id < b.id: return -1
+  if a.id > b.id: return 1
+  if a.is_fc_setter < b.is_fc_setter: return -1
+  if a.is_fc_setter > b.is_fc_setter: return 1
+  return 0
+
+def ConstantOutputOrder(a, b):
+  """Canonical output ordering for constants."""
+  if a.id < b.id: return -1
+  if a.id > b.id: return 1
+  return 0
+
+
+def _FormatNameList(names):
+  """Returns JavaScript array literal expression with one name per line."""
+  #names = sorted(names)
+  if len(names) <= 1:
+    expression_string = str(names)  # e.g.  ['length']
+  else:
+    expression_string = ',\n   '.join(str(names).split(','))
+    expression_string = expression_string.replace('[', '[\n    ')
+  return expression_string
+
+
+def IndentText(text, indent):
+  """Format lines of text with indent."""
+  def FormatLine(line):
+    if line.strip():
+      return '%s%s\n' % (indent, line)
+    else:
+      return '\n'
+  return ''.join(FormatLine(line) for line in text.split('\n'))
+
+# Given a sorted sequence of type identifiers, return an appropriate type
+# name
+def TypeName(typeIds, interface):
+  # Dynamically type this field for now.
+  return 'var'
+