Fix parser bug where that allowed invalid parenthesized expression wi…

…thout a warning. ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=130986781
google · Aug 23, 2016 · 6ffb18b · 6ffb18b
1 parent 7b8ae08
commit 6ffb18b
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Showing 2 changed files with 37 additions and 11 deletions.
diff --git a/src/com/google/javascript/jscomp/parsing/parser/Parser.java b/src/com/google/javascript/jscomp/parsing/parser/Parser.java
@@ -2633,14 +2633,24 @@ private ParseTree parseCoverParenthesizedExpressionAndArrowParameterList() {
     // Case ( )
     if (peek(TokenType.CLOSE_PAREN)) {
       eat(TokenType.CLOSE_PAREN);
-      return new FormalParameterListTree(getTreeLocation(start), ImmutableList.<ParseTree>of());
+      if (peek(TokenType.ARROW)) {
+        return new FormalParameterListTree(getTreeLocation(start), ImmutableList.<ParseTree>of());
+      } else {
+        reportError("invalid parenthesized expression");
+        return new MissingPrimaryExpressionTree(getTreeLocation(start));
+      }
     }
     // Case ( ... BindingIdentifier )
     if (peek(TokenType.SPREAD)) {
-      ParseTree result = new FormalParameterListTree(
+      ImmutableList<ParseTree> params = ImmutableList.of(
-          getTreeLocation(start), ImmutableList.of(parseParameter(ParamContext.IMPLEMENTATION)));
+          parseParameter(ParamContext.IMPLEMENTATION));
       eat(TokenType.CLOSE_PAREN);
-      return result;
+      if (peek(TokenType.ARROW)) {
+        return new FormalParameterListTree(getTreeLocation(start), params);
+      } else {
+        reportError("invalid parenthesized expression");
+        return new MissingPrimaryExpressionTree(getTreeLocation(start));
+      }
     }
     // For either of the two remaining cases:
     //     ( Expression )
@@ -2796,9 +2806,6 @@ private ParseTree parseAssignment(Expression expressionIn) {
     if (peek(TokenType.ARROW)) {
       return completeAssignmentExpressionParseAtArrow(left, expressionIn);
     }
-    if (left.type == ParseTreeType.FORMAL_PARAMETER_LIST) {
-      reportError("invalid paren expression");
-    }
 
     if (peekAssignmentOperator()) {
       left = transformLeftHandSideExpression(left);

diff --git a/test/com/google/javascript/jscomp/parsing/ParserTest.java b/test/com/google/javascript/jscomp/parsing/ParserTest.java
@@ -2634,15 +2634,34 @@ public void testRestParameters_ES5() {
         getRequiresEs6Message(Feature.REST_PARAMETERS));
   }
 
-  public void testExpressionsThatLookLikeParameters() {
+  public void testExpressionsThatLookLikeParameters1() {
     mode = LanguageMode.ECMASCRIPT6;
-    parseError("();", "invalid paren expression");
+    parseError("();", "invalid parenthesized expression");
     expectFeatures(Feature.REST_PARAMETERS);
-    parseError("(...xs);", "invalid paren expression");
+    parseError("(...xs);", "invalid parenthesized expression");
     parseError("(x, ...xs);", "A rest parameter must be in a parameter list.");
     parseError("(a, b, c, ...xs);", "A rest parameter must be in a parameter list.");
   }
 
+  public void testExpressionsThatLookLikeParameters2() {
+    mode = LanguageMode.ECMASCRIPT6;
+    parseError("!()", "invalid parenthesized expression");
+    parseError("().method", "invalid parenthesized expression");
+    parseError("() || a", "invalid parenthesized expression");
+    parseError("() && a", "invalid parenthesized expression");
+    parseError("x = ()", "invalid parenthesized expression");
+  }
+
+  public void testExpressionsThatLookLikeParameters3() {
+    expectFeatures(Feature.REST_PARAMETERS);
+    mode = LanguageMode.ECMASCRIPT6;
+    parseError("!(...x)", "invalid parenthesized expression");
+    parseError("(...x).method", "invalid parenthesized expression");
+    parseError("(...x) || a", "invalid parenthesized expression");
+    parseError("(...x) && a", "invalid parenthesized expression");
+    parseError("x = (...x)", "invalid parenthesized expression");
+  }
+
   public void testDefaultParametersWithRestParameters() {
     mode = LanguageMode.ECMASCRIPT6;
     expectFeatures(Feature.DEFAULT_PARAMETERS, Feature.REST_PARAMETERS);
@@ -2778,7 +2797,7 @@ public void testArrow1() {
         getRequiresEs6Message(Feature.ARROW_FUNCTIONS));
   }
 
-  public void testArrowInvalid() {
+  public void testArrowInvalid1() {
     mode = LanguageMode.ECMASCRIPT6;
     parseError("*()=>1;", "primary expression expected");
     expectFeatures(Feature.ARROW_FUNCTIONS);