Issue #1918 - m-c 1358246: Report syntax error for stray "async" keyword in object literal property name.

2 files changed, 39 insertions, 18 deletions

diff --git a/js/src/frontend/Parser.cpp b/js/src/frontend/Parser.cpp
index a66183b4a8..15c3448013 100644
--- a/js/src/frontend/Parser.cpp
+++ b/js/src/frontend/Parser.cpp
@@ -9771,6 +9771,21 @@ Parser<ParseHandler>::propertyName(YieldHandling yieldHandling,
             return null();
         break;
 
+      case TOK_STRING: {
+        propAtom.set(tokenStream.currentToken().atom());
+        uint32_t index;
+        if (propAtom->isIndex(&index)) {
+            propName = handler.newNumber(index, NoDecimal, pos());
+            if (!propName)
+                return null();
+            break;
+        }
+        propName = stringLiteral();
+        if (!propName)
+            return null();
+        break;
+      }
+
       case TOK_LB:
         propName = computedPropertyName(yieldHandling, maybeDecl, propList);
         if (!propName)
@@ -9784,7 +9799,7 @@ Parser<ParseHandler>::propertyName(YieldHandling yieldHandling,
         }
 
         propAtom.set(tokenStream.currentName());
-        // Do not look for accessor syntax on generators
+        // Do not look for accessor syntax on generator or async methods.
         if (isGenerator || isAsync || !(ltok == TOK_GET || ltok == TOK_SET)) {
             propName = handler.newObjectLiteralPropertyName(propAtom, pos());
             if (!propName)
@@ -9839,21 +9854,6 @@ Parser<ParseHandler>::propertyName(YieldHandling yieldHandling,
             return null();
         break;
       }
-
-      case TOK_STRING: {
-        propAtom.set(tokenStream.currentToken().atom());
-        uint32_t index;
-        if (propAtom->isIndex(&index)) {
-            propName = handler.newNumber(index, NoDecimal, pos());
-            if (!propName)
-                return null();
-            break;
-        }
-        propName = stringLiteral();
-        if (!propName)
-            return null();
-        break;
-      }
     }
 
     TokenKind tt;
@@ -9861,7 +9861,7 @@ Parser<ParseHandler>::propertyName(YieldHandling yieldHandling,
         return null();
 
     if (tt == TOK_COLON) {
-        if (isGenerator) {
+        if (isGenerator || isAsync) {
             error(JSMSG_BAD_PROP_ID);
             return null();
         }
@@ -9872,7 +9872,7 @@ Parser<ParseHandler>::propertyName(YieldHandling yieldHandling,
     if (TokenKindIsPossibleIdentifierName(ltok) &&
         (tt == TOK_COMMA || tt == TOK_RC || tt == TOK_ASSIGN))
     {
-        if (isGenerator) {
+        if (isGenerator || isAsync) {
             error(JSMSG_BAD_PROP_ID);
             return null();
         }
diff --git a/js/src/tests/ecma_2017/AsyncFunctions/async-property-name-error.js b/js/src/tests/ecma_2017/AsyncFunctions/async-property-name-error.js
new file mode 100644
index 0000000000..926794e5d0
--- /dev/null
+++ b/js/src/tests/ecma_2017/AsyncFunctions/async-property-name-error.js
@@ -0,0 +1,21 @@
+function assertSyntaxError(code) {
+    assertThrowsInstanceOf(() => { Function(code); }, SyntaxError, "Function:" + code);
+    assertThrowsInstanceOf(() => { eval(code); }, SyntaxError, "eval:" + code);
+    var ieval = eval;
+    assertThrowsInstanceOf(() => { ieval(code); }, SyntaxError, "indirect eval:" + code);
+}
+
+assertSyntaxError(`({async async: 0})`);
+assertSyntaxError(`({async async})`);
+assertSyntaxError(`({async async, })`);
+assertSyntaxError(`({async async = 0} = {})`);
+
+for (let decl of ["var", "let", "const"]) {
+    assertSyntaxError(`${decl} {async async: a} = {}`);
+    assertSyntaxError(`${decl} {async async} = {}`);
+    assertSyntaxError(`${decl} {async async, } = {}`);
+    assertSyntaxError(`${decl} {async async = 0} = {}`);
+}
+
+if (typeof reportCompare === "function")
+    reportCompare(true, true);