Auto merge of #9786 - peterjoel:fix_codegen_is_array_like, r=jdm

Fixed compile error in generated code, when webidl constructors have same number of args

One of the ways that generated code differentiates constructors is by comparing if the args are array-like. The generated code was calling a function `IsArrayLike` that no longer exists. I re-implemented it with a more rust-like naming scheme.

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

@@ -433,7 +433,7 @@ class CGMethodCall(CGThing):
             # XXXbz Now we're supposed to check for distinguishingArg being
             # an array or a platform object that supports indexed
             # properties... skip that last for now.  It's a bit of a pain.
-            pickFirstSignature("%s.get().isObject() && IsArrayLike(cx, &%s.get().toObject())" %
+            pickFirstSignature("%s.get().is_object() && is_array_like(cx, %s)" %
                                (distinguishingArg, distinguishingArg),
                                lambda s:
                                    (s[1][distinguishingIndex].type.isArray() or
@@ -442,7 +442,7 @@ class CGMethodCall(CGThing):
 
             # Check for Date objects
             # XXXbz Do we need to worry about security wrappers around the Date?
-            pickFirstSignature("%s.get().isObject() && JS_ObjectIsDate(cx, &%s.get().toObject())" %
+            pickFirstSignature("%s.get().is_object() && JS_ObjectIsDate(cx, &%s.get().to_object())" %
                                (distinguishingArg, distinguishingArg),
                                lambda s: (s[1][distinguishingIndex].type.isDate() or
                                           s[1][distinguishingIndex].type.isObject()))
@@ -5438,7 +5438,8 @@ class CGBindingRoot(CGThing):
             'dom::bindings::callback::{CallbackContainer,CallbackInterface,CallbackFunction}',
             'dom::bindings::callback::{CallSetup,ExceptionHandling}',
             'dom::bindings::callback::wrap_call_this_object',
-            'dom::bindings::conversions::{ConversionBehavior, DOM_OBJECT_SLOT, IDLInterface}',
+            'dom::bindings::conversions::{ConversionBehavior, DOM_OBJECT_SLOT}',
+            'dom::bindings::conversions::{IDLInterface, is_array_like}',
             'dom::bindings::conversions::{FromJSValConvertible, StringificationBehavior}',
             'dom::bindings::conversions::{ToJSValConvertible, jsid_to_str, native_from_handlevalue}',
             'dom::bindings::conversions::{native_from_object, private_from_object, root_from_object}',

components/script/dom/bindings/conversions.rs

@@ -47,7 +47,7 @@ use js::jsapi::{HandleId, HandleObject, HandleValue, JS_GetClass};
 use js::jsapi::{JSClass, JSContext, JSObject, MutableHandleValue};
 use js::jsapi::{JS_GetLatin1StringCharsAndLength, JS_GetReservedSlot};
 use js::jsapi::{JS_GetObjectAsArrayBufferView, JS_GetArrayBufferViewType};
-use js::jsapi::{JS_GetTwoByteStringCharsAndLength, JS_NewStringCopyN};
+use js::jsapi::{JS_GetTwoByteStringCharsAndLength, JS_IsArrayObject, JS_NewStringCopyN};
 use js::jsapi::{JS_StringHasLatin1Chars, JS_WrapValue};
 use js::jsapi::{Type};
 use js::jsval::{ObjectValue, StringValue};
@@ -458,3 +458,10 @@ pub fn array_buffer_view_to_vec_checked<T: ArrayBufferViewContents>(abv: *mut JS
         array_buffer_view_data_checked(abv).map(|data| data.to_vec())
     }
 }
+
+/// Returns whether `value` is an array-like object.
+/// Note: Currently only Arrays are supported.
+/// TODO: Expand this to support sequences and other array-like objects
+pub unsafe fn is_array_like(cx: *mut JSContext, value: HandleValue) -> bool {
+    JS_IsArrayObject(cx, value)
+}

components/script/dom/testbinding.rs

@@ -51,6 +51,16 @@ impl TestBinding {
     pub fn Constructor(global: GlobalRef) -> Fallible<Root<TestBinding>> {
         Ok(TestBinding::new(global))
     }
+
+    #[allow(unused_variables)]
+    pub fn Constructor_(global: GlobalRef, nums: Vec<f64>) -> Fallible<Root<TestBinding>> {
+        Ok(TestBinding::new(global))
+    }
+
+    #[allow(unused_variables)]
+    pub fn Constructor__(global: GlobalRef, num: f64) -> Fallible<Root<TestBinding>> {
+        Ok(TestBinding::new(global))
+    }
 }
 
 impl TestBindingMethods for TestBinding {

components/script/dom/webidls/TestBinding.webidl

@@ -69,7 +69,9 @@ dictionary TestDictionaryDefaults {
   object? nullableObjectValue = null;
 };
 
-[Constructor]
+[Constructor,
+ Constructor(sequence<unrestricted double> numberSequence),
+  Constructor(unrestricted double num)]
 interface TestBinding {
            attribute boolean booleanAttribute;
            attribute byte byteAttribute;