IDL: Support 'stringifier' keyword

Source/bindings/scripts/idl_definitions.py

Index: Source/bindings/scripts/idl_definitions.py
diff --git a/Source/bindings/scripts/idl_definitions.py b/Source/bindings/scripts/idl_definitions.py
index 50664ba12ef7addd5cb3cbc69484e0629231ba3d..45428e6883bc08b16567d95a85818401d9ca2f7e 100644
--- a/Source/bindings/scripts/idl_definitions.py
+++ b/Source/bindings/scripts/idl_definitions.py
@@ -48,8 +48,10 @@ IdlDefinitions
     IdlInterface
         IdlAttribute < TypedObject
         IdlConstant < TypedObject
+        IdlLiteral
         IdlOperation < TypedObject
             IdlArgument < TypedObject
+        IdlStringifier
     IdlException < IdlInterface
         (same contents as IdlInterface)
 
@@ -261,6 +263,7 @@ class IdlInterface(object):
         self.extended_attributes = {}
         self.operations = []
         self.parent = None
+        self.stringifier = None
         if not node:  # Early exit for IdlException.__init__
             return
 
@@ -287,6 +290,9 @@ class IdlInterface(object):
                 self.operations.append(IdlOperation(child))
             elif child_class == 'Inherit':
                 self.parent = child.GetName()
+            elif child_class == 'Stringifier':
+                self.stringifier = IdlStringifier(child)
+                self.process_stringifier()
             else:
                 raise ValueError('Unrecognized node class: %s' % child_class)
 
@@ -302,6 +308,17 @@ class IdlInterface(object):
         for operation in self.operations:
             operation.resolve_typedefs(typedefs)
 
+    def process_stringifier(self):
+        """Add the stringifier's synthesized 'toString' operation.
+
+        Also add the stringifier's attribute or named operation child, if it has
+        one, as a regular attribute/operation of this interface."""
+        if self.stringifier.attribute:
+            self.attributes.append(self.stringifier.attribute)
+        elif self.stringifier.operation and self.stringifier.operation.name:
+            self.operations.append(self.stringifier.operation)
+        self.operations.append(self.stringifier.synthesized_operation())
+
     def merge(self, other):
         """Merge in another interface's members (e.g., partial interface)"""
         self.attributes.extend(other.attributes)
@@ -562,6 +579,46 @@ def arguments_node_to_arguments(node):
 
 
 ################################################################################
+# Stringifiers
+################################################################################
+
+class IdlStringifier(object):
+    def __init__(self, node):
+        self.attribute = None
+        self.operation = None
+        self.extended_attributes = {}
+
+        for child in node.GetChildren():
+            child_class = child.GetClass()
+            if child_class == 'Attribute':
+                self.attribute = IdlAttribute(child)
+            elif child_class == 'Operation':
+                self.operation = IdlOperation(child)
+            elif child_class == 'ExtAttributes':
+                self.extended_attributes = ext_attributes_node_to_extended_attributes(child)
+            else:
+                raise ValueError('Unrecognized node class: %s' % child_class)
+
+        # Copy the stringifier's extended attributes (such as [Unforgable]) onto
+        # the underlying attribute or operation, if there is one.
+        if self.attribute or self.operation:
+            (self.attribute or self.operation).extended_attributes.update(
+                self.extended_attributes)
+
+    def synthesized_operation(self):
+        """Return a synthesized 'toString' operation from the stringifier."""

[Jens Widell, 2014/06/23 14:08:07]

I don't know if we think this is too much logic to put here in idl_definitions.
Synthesizing an IdlOperation like this was a convenient way to implement it.

[haraken, 2014/06/23 16:33:18]

Yeah, this looks like a bit too much logic in idl_defitions. We might want to
avoid writing "toString" or "ImplementedAs" here.

[Jens Widell, 2014/06/24 08:00:29]

Moved this code into interface_context() in v8_interface.py now. As a result,
the synthesized toString() method ends up last rather than where the stringifier
was declared in the interface, so there is now some superficial CG changes.

+        operation = IdlOperation()
+        operation.name = 'toString'
+        operation.idl_type = IdlType('DOMString')
+        operation.extended_attributes.update(self.extended_attributes)
+        if self.attribute:
+            operation.extended_attributes['ImplementedAs'] = self.attribute.name
+        elif self.operation and self.operation.name:
+            operation.extended_attributes['ImplementedAs'] = self.operation.name
+        return operation
+
+
+################################################################################
 # Extended attributes
 ################################################################################