Bug 1302692 - Fix error messages for labeled continue statements, remove some dead code. r=jwalden

--HG--
extra : rebase_source : 9f21e417a9598bb8786e52d84fa5a6ac145d2b6d

js/src/frontend/Parser.cpp

@@ -5546,17 +5546,21 @@ Parser<ParseHandler>::continueStatement(YieldHandling yieldHandling)
     };
 
     if (label) {
-        bool foundTarget = false;
         ParseContext::Statement* stmt = pc->innermostStatement();
+        bool foundLoop = false;
 
         for (;;) {
             stmt = ParseContext::Statement::findNearest(stmt, isLoop);
             if (!stmt) {
-                report(ParseError, false, null(), JSMSG_BAD_CONTINUE);
+                report(ParseError, false, null(),
+                       foundLoop ? JSMSG_LABEL_NOT_FOUND : JSMSG_BAD_CONTINUE);
                 return null();
             }
 
+            foundLoop = true;
+
             // Is it labeled by our label?
+            bool foundTarget = false;
             stmt = stmt->enclosing();
             while (stmt && stmt->is<ParseContext::LabelStatement>()) {
                 if (stmt->as<ParseContext::LabelStatement>().label() == label) {
@@ -5568,11 +5572,6 @@ Parser<ParseHandler>::continueStatement(YieldHandling yieldHandling)
             if (foundTarget)
                 break;
         }
-
-        if (!foundTarget) {
-            report(ParseError, false, null(), JSMSG_LABEL_NOT_FOUND);
-            return null();
-        }
     } else if (!pc->findInnermostStatement(isLoop)) {
         report(ParseError, false, null(), JSMSG_BAD_CONTINUE);
         return null();

js/src/jit-test/tests/parser/break-continue-errors.js

@@ -0,0 +1,22 @@
+load(libdir + "asserts.js");
+
+function test(s, expected) {
+    assertErrorMessage(() => Function(s), SyntaxError, expected);
+}
+
+test("A: continue;", "continue must be inside loop");
+test("A: continue B;", "continue must be inside loop");
+test("A: if (false) { continue; }", "continue must be inside loop");
+test("A: if (false) { continue B; }", "continue must be inside loop");
+test("while (false) { (() => { continue B; })(); }", "continue must be inside loop");
+test("B: while (false) { (() => { continue B; })(); }", "continue must be inside loop");
+
+test("do { continue B; } while (false);", "label not found");
+test("A: for (;;) { continue B; }", "label not found");
+test("A: while (false) { if (x) { continue B; } }", "label not found");
+test("A: while (false) { B: if (x) { continue B; } }", "label not found");
+
+test("A: if (false) { break B; }", "label not found");
+test("A: while (false) { break B; }", "label not found");
+test("A: while (true) { if (x) { break B; } }", "label not found");
+test("B: while (false) { (() => { break B; })(); }", "label not found");