add optional protoToAssign transformer

test/fixtures/transformation/optional-proto-to-assign/assignment-expression/actual.js

@@ -0,0 +1,5 @@
+console.log(foo.__proto__ = bar);
+
+console.log(foo[bar].__proto__ = bar);
+
+console.log(foo[bar()].__proto__ = bar);

test/fixtures/transformation/optional-proto-to-assign/assignment-expression/expected.js

@@ -0,0 +1,18 @@
+"use strict";
+
+var _foo, _foo$bar, _foo2;
+var _defaults = function (obj, defaults) {
+  for (var key in defaults) {
+    if (obj[key] === undefined) {
+      obj[key] = defaults[key];
+    }
+  }
+
+  return obj;
+};
+
+console.log((_foo = foo, _defaults(_foo, bar), _foo));
+
+console.log((_foo$bar = foo[bar], _defaults(_foo$bar, bar), _foo$bar));
+
+console.log((_foo2 = foo[bar()], _defaults(_foo2, bar), _foo2));

test/fixtures/transformation/optional-proto-to-assign/assignment-statement/actual.js

@@ -0,0 +1 @@
+obj.__proto__ = bar;

test/fixtures/transformation/optional-proto-to-assign/assignment-statement/expected.js

@@ -0,0 +1,13 @@
+"use strict";
+
+var _defaults = function (obj, defaults) {
+  for (var key in defaults) {
+    if (obj[key] === undefined) {
+      obj[key] = defaults[key];
+    }
+  }
+
+  return obj;
+};
+
+_defaults(obj, bar);

test/fixtures/transformation/optional-proto-to-assign/class/actual.js

@@ -0,0 +1,3 @@
+class Foo extends Bar {
+
+}

test/fixtures/transformation/optional-proto-to-assign/class/expected.js

@@ -0,0 +1,36 @@
+"use strict";
+
+var _defaults = function (obj, defaults) {
+  for (var key in defaults) {
+    if (obj[key] === undefined) {
+      obj[key] = defaults[key];
+    }
+  }
+
+  return obj;
+};
+
+var _inherits = function (child, parent) {
+  child.prototype = Object.create(parent && parent.prototype, {
+    constructor: {
+      value: child,
+      enumerable: false,
+      writable: true,
+      configurable: true
+    }
+  });
+  if (parent) _defaults(child, parent);
+};
+
+var Foo = (function () {
+  var _Bar = Bar;
+  var Foo = function Foo() {
+    if (_Bar) {
+      _Bar.apply(this, arguments);
+    }
+  };
+
+  _inherits(Foo, _Bar);
+
+  return Foo;
+})();

test/fixtures/transformation/optional-proto-to-assign/object-literal/actual.js

@@ -0,0 +1,13 @@
+var foo = {
+  __proto__: bar
+};
+
+var foo = {
+  bar: "foo",
+  __proto__: bar
+};
+
+var foo = {
+  __proto__: bar,
+  bar: "foo"
+};

test/fixtures/transformation/optional-proto-to-assign/object-literal/expected.js

@@ -0,0 +1,10 @@
+"use strict";
+
+var foo = Object.assign({}, bar);
+
+var foo = Object.assign({}, bar, {
+  bar: "foo" });
+
+var foo = Object.assign({}, bar, {
+  bar: "foo"
+});

test/fixtures/transformation/optional-proto-to-assign/options.json

@@ -0,0 +1,3 @@
+{
+  "optional": ["protoToAssign"]
+}