1 files changed, 104 insertions, 0 deletions
diff --git a/test/language/expressions/optional-chaining/member-expression.js b/test/language/expressions/optional-chaining/member-expression.js
new file mode 100644
index 000000000..0651d393e
--- /dev/null
+++ b/test/language/expressions/optional-chaining/member-expression.js
@@ -0,0 +1,104 @@
+// Copyright 2019 Google, Inc.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: prod-OptionalExpression
+description: >
+  optional chain on member expression
+info: |
+  Left-Hand-Side Expressions
+    OptionalExpression:
+      MemberExpression OptionalChain
+features: [optional-chaining]
+---*/
+
+// PrimaryExpression
+//   IdentifierReference
+const a = {b: 22};
+assert.sameValue(22, a?.b);
+//   this
+function fn () {
+  return this?.a
+}
+assert.sameValue(33, fn.call({a: 33}));
+//   Literal
+assert.sameValue(undefined, "hello"?.a);
+assert.sameValue(undefined, null?.a);
+//   ArrayLiteral
+assert.sameValue(2, [1, 2]?.[1]);
+//   ObjectLiteral
+assert.sameValue(44, {a: 44}?.a);
+//   FunctionExpression
+assert.sameValue('a', (function a () {}?.name));
+//   ClassExpression
+assert.sameValue('Foo', (class Foo {}?.name));
+//   GeneratorFunction
+assert.sameValue('a', (function * a () {}?.name));
+//   AsyncFunctionExpression
+// assert.sameValue('a', (async function a () {}?.name)); // Not available in ES7
+//   AsyncGeneratorExpression
+// assert.sameValue('a', (async function * a () {}?.name)); // Not available in ES7
+//   RegularExpressionLiteral
+assert.sameValue(true, /[a-z]/?.test('a'));
+//   TemplateLiteral
+assert.sameValue('h', `hello`?.[0]);
+//   CoverParenthesizedExpressionAndArrowParameterList
+assert.sameValue(undefined, ({a: 33}, null)?.a);
+assert.sameValue(33, (undefined, {a: 33})?.a);
+
+//  MemberExpression [ Expression ]
+const arr = [{a: 33}];
+assert.sameValue(33, arr[0]?.a);
+assert.sameValue(undefined, arr[1]?.a);
+
+//  MemberExpression .IdentifierName
+const obj = {a: {b: 44}};
+assert.sameValue(44, obj.a?.b);
+assert.sameValue(undefined, obj.c?.b);
+
+//  MemberExpression TemplateLiteral
+function f2 () {
+  return {a: 33};
+}
+function f3 () {}
+assert.sameValue(33, f2`hello world`?.a);
+assert.sameValue(undefined, f3`hello world`?.a);
+
+//  MemberExpression SuperProperty
+class A {
+  a () {}
+  undf () {
+    return super.a?.c;
+  }
+}
+class B extends A {
+  dot () {
+    return super.a?.name;
+  }
+  expr () {
+    return super['a']?.name;
+  }
+  undf2 () {
+    return super.b?.c;
+  }
+}
+const subcls = new B();
+assert.sameValue('a', subcls.dot());
+assert.sameValue('a', subcls.expr());
+assert.sameValue(undefined, subcls.undf2());
+assert.sameValue(undefined, (new A()).undf());
+
+// MemberExpression MetaProperty
+class C {
+  constructor () {
+    assert.sameValue(undefined, new.target?.a);
+  }
+}
+new C();
+
+// new MemberExpression Arguments
+class D {
+  constructor (val) {
+    this.a = val;
+  }
+}
+assert.sameValue(99, new D(99)?.a);