Give JavaScript value objects useful constructor.name values (#936)

nex3 · web-flow · commit eeeac1d689b0 · 2020-01-17T14:46:10.000-08:00
Closes #810
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -27,11 +27,16 @@
 
 * Add the variables `$pi` and `$e` to the built-in "sass:math" module.
 
+### JavaScript API
+
+* `constructor.value` fields on value objects now match their Node Sass
+  equivalents.
+
 ## 1.24.5
 
 * Highlight contextually-relevant sections of the stylesheet in error messages,
   rather than only highlighting the section where the error was detected.
-
+  
 ## 1.24.4
 
 ### JavaScript API
diff --git a/lib/src/node/utils.dart b/lib/src/node/utils.dart
@@ -58,12 +58,14 @@ void jsForEach(Object object, void callback(Object key, Object value)) {
   }
 }
 
-/// Creates a JS class with the given [constructor] and [methods].
+/// Creates a JS class with the given [name], [constructor] and [methods].
 ///
 /// Both [constructor] and [methods] should take an initial `thisArg` parameter,
 /// representing the object being constructed.
-Function createClass(Function constructor, Map<String, Function> methods) {
+Function createClass(
+    String name, Function constructor, Map<String, Function> methods) {
   var klass = allowInteropCaptureThis(constructor);
+  _defineProperty(klass, 'name', _PropertyDescriptor(value: name));
   var prototype = getProperty(klass, 'prototype');
   methods.forEach((name, body) {
     setProperty(prototype, name, allowInteropCaptureThis(body));
@@ -77,6 +79,18 @@ external Object _getPrototypeOf(Object object);
 @JS("Object.setPrototypeOf")
 external void _setPrototypeOf(Object object, Object prototype);
 
+@JS("Object.defineProperty")
+external void _defineProperty(
+    Object object, String name, _PropertyDescriptor prototype);
+
+@JS()
+@anonymous
+class _PropertyDescriptor {
+  external Object get value;
+
+  external factory _PropertyDescriptor({Object value});
+}
+
 @JS("Object.create")
 external Object _create(Object prototype);
 
diff --git a/lib/src/node/value/color.dart b/lib/src/node/value/color.dart
@@ -20,7 +20,7 @@ Object newNodeSassColor(SassColor value) =>
     callConstructor(colorConstructor, [null, null, null, null, value]);
 
 /// The JS constructor for the `sass.types.Color` class.
-final Function colorConstructor = createClass(
+final Function colorConstructor = createClass('SassColor',
     (_NodeSassColor thisArg, num redOrArgb,
         [num green, num blue, num alpha, SassColor dartValue]) {
   if (dartValue != null) {
diff --git a/lib/src/node/value/list.dart b/lib/src/node/value/list.dart
@@ -21,8 +21,9 @@ Object newNodeSassList(SassList value) =>
     callConstructor(listConstructor, [null, null, value]);
 
 /// The JS constructor for the `sass.types.List` class.
-final Function listConstructor = createClass((_NodeSassList thisArg, int length,
-    [bool commaSeparator, SassList dartValue]) {
+final Function listConstructor = createClass('SassList',
+    (_NodeSassList thisArg, int length,
+        [bool commaSeparator, SassList dartValue]) {
   thisArg.dartValue = dartValue ??
       SassList(Iterable.generate(length, (_) => sassNull),
           (commaSeparator ?? true) ? ListSeparator.comma : ListSeparator.space);
diff --git a/lib/src/node/value/map.dart b/lib/src/node/value/map.dart
@@ -21,8 +21,8 @@ Object newNodeSassMap(SassMap value) =>
     callConstructor(mapConstructor, [null, value]);
 
 /// The JS constructor for the `sass.types.Map` class.
-final Function mapConstructor =
-    createClass((_NodeSassMap thisArg, int length, [SassMap dartValue]) {
+final Function mapConstructor = createClass('SassMap',
+    (_NodeSassMap thisArg, int length, [SassMap dartValue]) {
   thisArg.dartValue = dartValue ??
       SassMap(Map.fromIterables(Iterable.generate(length, (i) => SassNumber(i)),
           Iterable.generate(length, (_) => sassNull)));
diff --git a/lib/src/node/value/number.dart b/lib/src/node/value/number.dart
@@ -20,7 +20,7 @@ Object newNodeSassNumber(SassNumber value) =>
     callConstructor(numberConstructor, [null, null, value]);
 
 /// The JS constructor for the `sass.types.Number` class.
-final Function numberConstructor = createClass(
+final Function numberConstructor = createClass('SassNumber',
     (_NodeSassNumber thisArg, num value, [String unit, SassNumber dartValue]) {
   thisArg.dartValue = dartValue ?? _parseNumber(value, unit);
 }, {
diff --git a/lib/src/node/value/string.dart b/lib/src/node/value/string.dart
@@ -20,7 +20,7 @@ Object newNodeSassString(SassString value) =>
     callConstructor(stringConstructor, [null, value]);
 
 /// The JS constructor for the `sass.types.String` class.
-final Function stringConstructor = createClass(
+final Function stringConstructor = createClass('SassString',
     (_NodeSassString thisArg, String value, [SassString dartValue]) {
   thisArg.dartValue = dartValue ?? SassString(value, quotes: false);
 }, {
diff --git a/test/node_api/api.dart b/test/node_api/api.dart
@@ -85,13 +85,20 @@ class NodeSassBooleanClass implements Function {
   external NodeSassBoolean get FALSE;
 }
 
+@JS()
+class Constructor {
+  external String get name;
+}
+
 @JS()
 class NodeSassBoolean {
+  external Constructor get constructor;
   external bool getValue();
 }
 
 @JS()
 class NodeSassColor {
+  external Constructor get constructor;
   external int getR();
   external void setR(num value);
   external int getG();
@@ -104,6 +111,7 @@ class NodeSassColor {
 
 @JS()
 class NodeSassList {
+  external Constructor get constructor;
   external Object getValue(int index);
   external void setValue(int index, Object value);
   external bool getSeparator();
@@ -113,6 +121,7 @@ class NodeSassList {
 
 @JS()
 class NodeSassMap {
+  external Constructor get constructor;
   external Object getValue(int index);
   external void setValue(int index, Object value);
   external Object getKey(int index);
@@ -123,11 +132,17 @@ class NodeSassMap {
 @JS()
 class NodeSassNullClass implements Function {
   external Object call();
-  external Object get NULL;
+  external NodeSassNull get NULL;
+}
+
+@JS()
+class NodeSassNull implements Function {
+  external Constructor get constructor;
 }
 
 @JS()
 class NodeSassNumber {
+  external Constructor get constructor;
   external num getValue();
   external void setValue(int value);
   external String getUnit();
@@ -136,6 +151,7 @@ class NodeSassNumber {
 
 @JS()
 class NodeSassString {
+  external Constructor get constructor;
   external String getValue();
   external void setValue(String value);
 }
diff --git a/test/node_api/value/boolean_test.dart b/test/node_api/value/boolean_test.dart
@@ -25,6 +25,11 @@ void main() {
       expect(value, isJSInstanceOf(sass.types.Boolean));
       expect(value.getValue(), isFalse);
     });
+
+    test("has a useful .constructor.name", () {
+      expect(parseValue<NodeSassBoolean>("true").constructor.name,
+          equals("SassBoolean"));
+    });
   });
 
   group("from a constant", () {
@@ -39,6 +44,10 @@ void main() {
       expect(value, isJSInstanceOf(sass.types.Boolean));
       expect(value.getValue(), isFalse);
     });
+
+    test("has a useful .constructor.name", () {
+      expect(sass.types.Boolean.FALSE.constructor.name, equals("SassBoolean"));
+    });
   });
 
   test("the constructor throws", () {
diff --git a/test/node_api/value/color_test.dart b/test/node_api/value/color_test.dart
@@ -93,6 +93,10 @@ void main() {
       color.setB(0.5);
       expect(color.getB(), equals(1));
     });
+
+    test("has a useful .constructor.name", () {
+      expect(color.constructor.name, equals("SassColor"));
+    });
   });
 
   group("from a constructor", () {
@@ -120,5 +124,10 @@ void main() {
       expect(color.getB(), equals(0x78));
       expect(color.getA(), equals(0x12 / 0xff));
     });
+
+    test("has a useful .constructor.name", () {
+      expect(callConstructor(sass.types.Color, [11, 12, 13]).constructor.name,
+          equals("SassColor"));
+    });
   });
 }
diff --git a/test/node_api/value/list_test.dart b/test/node_api/value/list_test.dart
@@ -39,6 +39,10 @@ void main() {
       expect(args.getValue(1), isJSInstanceOf(sass.types.String));
       expect(args.getValue(2), isJSInstanceOf(sass.types.Color));
     });
+
+    test("has a useful .constructor.name", () {
+      expect(args.constructor.name, equals("SassList"));
+    });
   });
 
   group("a list", () {
@@ -107,6 +111,10 @@ void main() {
         expect(parseValue("()").getSeparator(), isFalse);
         expect(parseValue("join((), 1px)").getSeparator(), isFalse);
       });
+
+      test("has a useful .constructor.name", () {
+        expect(list.constructor.name, equals("SassList"));
+      });
     });
 
     group("from a constructor", () {
@@ -138,6 +146,11 @@ void main() {
         var list = callConstructor(sass.types.List, [3, false]);
         expect(list.getSeparator(), isFalse);
       });
+
+      test("has a useful .constructor.name", () {
+        expect(callConstructor(sass.types.List, [3]).constructor.name,
+            equals("SassList"));
+      });
     });
   });
 }
diff --git a/test/node_api/value/map_test.dart b/test/node_api/value/map_test.dart
@@ -102,6 +102,10 @@ void main() {
       map.setKey(0, callConstructor(sass.types.String, ["a"]));
       expect((map.getKey(0) as NodeSassString).getValue(), equals("a"));
     });
+
+    test("has a useful .constructor.name", () {
+      expect(map.constructor.name, equals("SassMap"));
+    });
   });
 
   group("from a constructor", () {
@@ -132,5 +136,10 @@ void main() {
       map.setValue(1, sass.types.Boolean.TRUE);
       expect(map.getValue(1), equals(sass.types.Boolean.TRUE));
     });
+
+    test("has a useful .constructor.name", () {
+      expect(callConstructor(sass.types.Map, [3]).constructor.name,
+          equals("SassMap"));
+    });
   });
 }
diff --git a/test/node_api/value/null_test.dart b/test/node_api/value/null_test.dart
@@ -14,9 +14,9 @@ import 'utils.dart';
 
 void main() {
   group("from a parameter", () {
-    Object value;
+    NodeSassNull value;
     setUp(() {
-      value = parseValue("null");
+      value = parseValue<NodeSassNull>("null");
     });
 
     test("is instanceof Null", () {
@@ -26,6 +26,16 @@ void main() {
     test("equals NULL", () {
       expect(value, equals(sass.types.Null.NULL));
     });
+
+    test("has a useful .constructor.name", () {
+      expect(value.constructor.name, equals("SassNull"));
+    });
+  });
+
+  group("from a constant", () {
+    test("has a useful .constructor.name", () {
+      expect(sass.types.Null.NULL.constructor.name, equals("SassNull"));
+    });
   });
 
   test("the constructor throws", () {
diff --git a/test/node_api/value/number_test.dart b/test/node_api/value/number_test.dart
@@ -141,6 +141,10 @@ void main() {
       expect(() => number.setUnit("*px"), throwsA(anything));
       expect(() => number.setUnit("px/deg/ms"), throwsA(anything));
     });
+
+    test("has a useful .constructor.name", () {
+      expect(number.constructor.name, equals("SassNumber"));
+    });
   });
 
   group("from a constructor", () {
@@ -170,5 +174,10 @@ void main() {
               }))),
           equalsIgnoringWhitespace("a { b: 1px; }"));
     });
+
+    test("has a useful .constructor.name", () {
+      expect(callConstructor(sass.types.Number, [123]).constructor.name,
+          equals("SassNumber"));
+    });
   });
 }
diff --git a/test/node_api/value/string_test.dart b/test/node_api/value/string_test.dart
@@ -59,6 +59,10 @@ void main() {
               }))),
           equalsIgnoringWhitespace('a { b: bar; }'));
     });
+
+    test("has a useful .constructor.name", () {
+      expect(string.constructor.name, equals("SassString"));
+    });
   });
 
   group("from a constructor", () {
@@ -80,5 +84,10 @@ void main() {
               }))),
           equalsIgnoringWhitespace("a { b: foo; }"));
     });
+
+    test("has a useful .constructor.name", () {
+      expect(callConstructor(sass.types.String, ["foo"]).constructor.name,
+          equals("SassString"));
+    });
   });
 }
