chore: address code review

test/language/expressions/optional-chaining/call-expression.js

@@ -0,0 +1,20 @@
+// Copyright 2019 Google, Inc.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: prod-OptionalExpression
+desc: >
+  optional chain on call expression
+info: |
+  Left-Hand-Side Expressions
+    OptionalExpression:
+      CallExpression OptionalChain
+features: [optional-chaining]
+---*/
+
+function fn () {
+  return {a: 33};
+};
+
+// CallExpression Arguments
+assert.sameValue(33, fn()?.a);
+assert.sameValue(undefined, fn()?.b);

test/language/expressions/optional-chaining/early-errors-tail-position-template-string-esi.js

@@ -0,0 +1,25 @@
+// Copyright 2019 Google, Inc.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: prod-OptionalExpression
+desc: >
+  template string passed to tail position of optional chain
+info: |
+  Static Semantics: Early Errors
+    OptionalChain:
+      ?.TemplateLiteral
+      OptionalChain TemplateLiteral
+features: [optional-chaining]
+negative:
+  type: SyntaxError
+  phase: parse
+---*/
+
+$DONOTEVALUATE();
+
+const a = {fn() {}};
+
+// This production exists in order to prevent automatic semicolon
+// insertion rules.
+a?.fn
+  `hello`

test/language/expressions/optional-chaining/early-errors-tail-position-template-string.js

@@ -1,8 +1,10 @@
+// Copyright 2019 Google, Inc.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: pending
-info: |
+esid: prod-OptionalExpression
+desc: >
   template string passed to tail position of optional chain
-description: >
+info: |
   Static Semantics: Early Errors
     OptionalChain:
       ?.TemplateLiteral
@@ -17,5 +19,6 @@ $DONOTEVALUATE();
 
 const a = {fn() {}};
 
-a?.fn
-  `hello`;
+// This production exists in order to prevent automatic semicolon
+// insertion rules.
+a?.fn`hello`;

test/language/expressions/optional-chaining/member-expression-optional-chain.js → test/language/expressions/optional-chaining/member-expression.js

@@ -1,14 +1,19 @@
+// Copyright 2019 Google, Inc.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: pending
-info: |
+esid: prod-OptionalExpression
+desc: >
   optional chain on member expression
-description: >
+info: |
   Left-Hand-Side Expressions
     OptionalExpression:
       MemberExpression OptionalChain
 features: [optional-chaining]
 ---*/
 
+// PrimaryExpression
+//   IdentifierReference
+
 const arr = [10, 11];
 const fn = (arg1, arg2) => {
   return arg1 + arg2;

test/language/expressions/optional-chaining/optional-expression.js

@@ -0,0 +1,27 @@
+// Copyright 2019 Google, Inc.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: prod-OptionalExpression
+desc: >
+  optional chain on recursive optional expression
+info: |
+  Left-Hand-Side Expressions
+    OptionalExpression:
+      OptionalExpression OptionalChain
+features: [optional-chaining]
+---*/
+
+const obj = {
+  a: {
+    b: 22
+  }
+};
+
+function fn () {
+  return {};
+}
+
+// MemberExpression
+assert.sameValue(22, (obj?.a)?.b);
+// CallExpression
+assert.sameValue(undefined, (fn()?.a)?.b);

test/language/expressions/optional-chaining/punctuator-decimal-lookahead.js

@@ -1,13 +1,15 @@
+// Copyright 2019 Google, Inc.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: pending
-info: |
+esid: prod-OptionalExpression
+desc: >
   ternary operation with decimal does not evaluate as optional chain 
-description: >
+info: |
   Punctuators
     OptionalChainingPunctuator::
       ?.[lookahead ∉ DecimalDigit]
 features: [optional-chaining]
 ---*/
 
-const value = true ?.30 : false
-assert.sameValue(.30, value)
+const value = true ?.30 : false;
+assert.sameValue(.30, value);

test/language/expressions/optional-chaining/runtime-semantics-evaluation.js

@@ -1,8 +1,10 @@
+// Copyright 2019 Google, Inc.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: pending
-info: |
+esid: prod-OptionalExpression
+desc: >
   accessing optional value on undefined or null returns undefined.
-description: >
+info: |
   If baseValue is undefined or null, then
     Return undefined.
 features: [optional-chaining]
@@ -12,3 +14,5 @@ const nul = null;
 const undf = undefined;
 assert.sameValue(undefined, nul?.a);
 assert.sameValue(undefined, undf?.b);
+assert.sameValue(undefined, null?.a);
+assert.sameValue(undefined, undefined?.b);

test/language/expressions/optional-chaining/short-circuiting.js

@@ -1,16 +1,22 @@
+// Copyright 2019 Google, Inc.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: pending
+esid: prod-OptionalExpression
+desc: >
+  demonstrate syntax-based short-circuiting.
 info: |
   If the expression on the LHS of ?. evaluates to null/undefined, the RHS is
   not evaluated
-description: >
-  demonstrate syntax-based short-circuiting.
 features: [optional-chaining]
 ---*/
 
 const a = undefined;
 let x = 1;
+
 a?.[++x] // short-circuiting.
 a?.b.c(++x).d; // long short-circuiting.
 
+undefined?.[++x] // short-circuiting.
+undefined?.b.c(++x).d; // long short-circuiting.
+
 assert.sameValue(1, x);

test/language/expressions/optional-chaining/static-semantics-simple-assignment.js

@@ -1,8 +1,11 @@
+
+// Copyright 2019 Google, Inc.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: pending
-info: |
+esid: prod-OptionalExpression
+desc: >
   an optional expression cannot be target of assignment
-description: >
+info: |
   Static Semantics: IsValidSimpleAssignmentTarget
     LeftHandSideExpression:
       OptionalExpression