Port modern callback handling code from Gecko, and copy related WebIDL parser bits too.

src/components/script/dom/bindings/codegen/parser/WebIDL.py

@@ -464,6 +464,10 @@ class IDLInterface(IDLObjectWithScope):
         self._callback = False
         self._finished = False
         self.members = []
+        # namedConstructors needs deterministic ordering because bindings code
+        # outputs the constructs in the order that namedConstructors enumerates
+        # them.
+        self.namedConstructors = list()
         self.implementedInterfaces = set()
         self._consequential = False
         self._isPartial = True
@@ -696,6 +700,9 @@ class IDLInterface(IDLObjectWithScope):
             if identifier == "TreatNonCallableAsNull":
                 raise WebIDLError("TreatNonCallableAsNull cannot be specified on interfaces",
                                   [attr.location, self.location])
+            if identifier == "TreatNonObjectAsNull":
+                raise WebIDLError("TreatNonObjectAsNull cannot be specified on interfaces",
+                                  [attr.location, self.location])
             elif identifier == "NoInterfaceObject":
                 if not attr.noArguments():
                     raise WebIDLError("[NoInterfaceObject] must take no arguments",
@@ -1049,11 +1056,12 @@ class IDLType(IDLObject):
         assert False # Override me!
 
     def treatNonCallableAsNull(self):
-        if not (self.nullable() and self.tag() == IDLType.Tags.callback):
-            raise WebIDLError("Type %s cannot be TreatNonCallableAsNull" % self,
-                              [self.location])
+        assert self.tag() == IDLType.Tags.callback
+        return self.nullable() and self.inner._treatNonCallableAsNull
 
-        return hasattr(self, "_treatNonCallableAsNull")
+    def treatNonObjectAsNull(self):
+        assert self.tag() == IDLType.Tags.callback
+        return self.nullable() and self.inner._treatNonObjectAsNull
 
     def markTreatNonCallableAsNull(self):
         assert not self.treatNonCallableAsNull()
@@ -2189,6 +2197,7 @@ class IDLArgument(IDLObjectWithIdentifier):
         self._isComplete = False
         self.enforceRange = False
         self.clamp = False
+        self._allowTreatNonCallableAsNull = False
 
         assert not variadic or optional
 
@@ -2215,6 +2224,8 @@ class IDLArgument(IDLObjectWithIdentifier):
                     raise WebIDLError("[EnforceRange] and [Clamp] are mutually exclusive",
                                       [self.location]);
                 self.enforceRange = True
+            elif identifier == "TreatNonCallableAsNull":
+                self._allowTreatNonCallableAsNull = True
             else:
                 raise WebIDLError("Unhandled extended attribute on an argument",
                                   [attribute.location])
@@ -2247,6 +2258,9 @@ class IDLArgument(IDLObjectWithIdentifier):
                                                                self.location)
             assert self.defaultValue
 
+    def allowTreatNonCallableAsNull(self):
+        return self._allowTreatNonCallableAsNull
+
     def _getDependentObjects(self):
         deps = set([self.type])
         if self.defaultValue:
@@ -2269,6 +2283,12 @@ class IDLCallbackType(IDLType, IDLObjectWithScope):
             for argument in arguments:
                 argument.resolve(self)
 
+        self._treatNonCallableAsNull = False
+        self._treatNonObjectAsNull = False
+
+    def module(self):
+        return self.location.filename().split('/')[-1].split('.webidl')[0] + 'Binding'
+
     def isCallback(self):
         return True
 
@@ -2308,6 +2328,21 @@ class IDLCallbackType(IDLType, IDLObjectWithScope):
         return (other.isPrimitive() or other.isString() or other.isEnum() or
                 other.isNonCallbackInterface() or other.isDate())
 
+    def addExtendedAttributes(self, attrs):
+        unhandledAttrs = []
+        for attr in attrs:
+            if attr.identifier() == "TreatNonCallableAsNull":
+                self._treatNonCallableAsNull = True
+            elif attr.identifier() == "TreatNonObjectAsNull":
+                self._treatNonObjectAsNull = True
+            else:
+                unhandledAttrs.append(attr)
+        if self._treatNonCallableAsNull and self._treatNonObjectAsNull:
+            raise WebIDLError("Cannot specify both [TreatNonCallableAsNull] "
+                              "and [TreatNonObjectAsNull]", [self.location])
+        if len(unhandledAttrs) != 0:
+            IDLType.addExtendedAttributes(self, unhandledAttrs)
+
     def _getDependentObjects(self):
         return set([self._returnType] + self._arguments)