Auto merge of #9304 - ecoal95:sequence-in-unions, r=nox

webidl: Implement sequences in unions

Unblocks #9053

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components/script/dom/bindings/codegen/CodegenRust.py

@@ -700,10 +700,13 @@ def getJSToNativeConversionInfo(type, descriptorProvider, failureCode=None,
         raise TypeError("Can't handle array arguments yet")
 
     if type.isSequence():
-        # Use the same type that for return values
-        declType = getRetvalDeclarationForType(type, descriptorProvider)
+        innerInfo = getJSToNativeConversionInfo(type.unroll(), descriptorProvider)
+        declType = CGWrapper(innerInfo.declType, pre="Vec<", post=">")
         config = getConversionConfigForType(type, isEnforceRange, isClamp, treatNullAs)
 
+        if type.nullable():
+            declType = CGWrapper(declType, pre="Option<", post=" >")
+
         templateBody = ("match FromJSValConvertible::from_jsval(cx, ${val}, %s) {\n"
                         "    Ok(value) => value,\n"
                         "    Err(()) => { %s },\n"
@@ -1221,7 +1224,7 @@ def getConversionConfigForType(type, isEnforceRange, isClamp, treatNullAs):
             return "StringificationBehavior::Default"
         else:
             return treatAs[treatNullAs]
-    if type.isInteger():
+    if type.isPrimitive() and type.isInteger():
         if isEnforceRange:
             return "ConversionBehavior::EnforceRange"
         elif isClamp:
@@ -3571,8 +3574,8 @@ def getUnionTypeTemplateVars(type, descriptorProvider):
     # for getJSToNativeConversionInfo.
     # Also, for dictionaries we would need to handle conversion of
     # null/undefined to the dictionary correctly.
-    if type.isDictionary() or type.isSequence():
-        raise TypeError("Can't handle dictionaries or sequences in unions")
+    if type.isDictionary():
+        raise TypeError("Can't handle dictionaries in unions")
 
     if type.isGeckoInterface():
         name = type.inner.identifier.name
@@ -3580,7 +3583,11 @@ def getUnionTypeTemplateVars(type, descriptorProvider):
     elif type.isEnum():
         name = type.inner.identifier.name
         typeName = name
-    elif type.isArray() or type.isSequence():
+    elif type.isSequence():
+        name = type.name
+        inner = getUnionTypeTemplateVars(type.unroll(), descriptorProvider)
+        typeName = "Vec<" + inner["typeName"] + ">"
+    elif type.isArray():
         name = str(type)
         # XXXjdm dunno about typeName here
         typeName = "/*" + type.name + "*/"
@@ -3664,22 +3671,22 @@ class CGUnionConversionStruct(CGThing):
         names = []
         conversions = []
 
+        def get_name(memberType):
+            if self.type.isGeckoInterface():
+                return memberType.inner.identifier.name
+
+            return memberType.name
+
+        def get_match(name):
+            return (
+                "match %s::TryConvertTo%s(cx, value) {\n"
+                "    Err(_) => return Err(()),\n"
+                "    Ok(Some(value)) => return Ok(%s::e%s(value)),\n"
+                "    Ok(None) => (),\n"
+                "}\n") % (self.type, name, self.type, name)
+
         interfaceMemberTypes = filter(lambda t: t.isNonCallbackInterface(), memberTypes)
         if len(interfaceMemberTypes) > 0:
-            def get_name(memberType):
-                if self.type.isGeckoInterface():
-                    return memberType.inner.identifier.name
-
-                return memberType.name
-
-            def get_match(name):
-                return (
-                    "match %s::TryConvertTo%s(cx, value) {\n"
-                    "    Err(_) => return Err(()),\n"
-                    "    Ok(Some(value)) => return Ok(%s::e%s(value)),\n"
-                    "    Ok(None) => (),\n"
-                    "}\n") % (self.type, name, self.type, name)
-
             typeNames = [get_name(memberType) for memberType in interfaceMemberTypes]
             interfaceObject = CGList(CGGeneric(get_match(typeName)) for typeName in typeNames)
             names.extend(typeNames)
@@ -3689,7 +3696,9 @@ class CGUnionConversionStruct(CGThing):
         arrayObjectMemberTypes = filter(lambda t: t.isArray() or t.isSequence(), memberTypes)
         if len(arrayObjectMemberTypes) > 0:
             assert len(arrayObjectMemberTypes) == 1
-            raise TypeError("Can't handle arrays or sequences in unions.")
+            typeName = arrayObjectMemberTypes[0].name
+            arrayObject = CGGeneric(get_match(typeName))
+            names.append(typeName)
         else:
             arrayObject = None
 
@@ -3727,8 +3736,12 @@ class CGUnionConversionStruct(CGThing):
 
         hasObjectTypes = interfaceObject or arrayObject or dateObject or nonPlatformObject or object
         if hasObjectTypes:
-            assert interfaceObject
-            templateBody = CGList([interfaceObject], "\n")
+            assert interfaceObject or arrayObject
+            templateBody = CGList([], "\n")
+            if interfaceObject:
+                templateBody.append(interfaceObject)
+            if arrayObject:
+                templateBody.append(arrayObject)
             conversions.append(CGIfWrapper("value.get().is_object()", templateBody))
 
         otherMemberTypes = [

components/script/dom/bindings/conversions.rs

@@ -94,6 +94,17 @@ impl<T: Float + FromJSValConvertible<Config=()>> FromJSValConvertible for Finite
     }
 }
 
+impl <T: Reflectable + IDLInterface> FromJSValConvertible for Root<T> {
+    type Config = ();
+
+    unsafe fn from_jsval(_cx: *mut JSContext,
+                         value: HandleValue,
+                         _config: Self::Config)
+        -> Result<Root<T>, ()> {
+        root_from_handlevalue(value)
+    }
+}
+
 /// Convert the given `jsid` to a `DOMString`. Fails if the `jsid` is not a
 /// string, or if the string does not contain valid UTF-16.
 pub fn jsid_to_str(cx: *mut JSContext, id: HandleId) -> DOMString {