Add regression test

Effectively testing for this regression requires making the parser more
lenient (the test would otherwise have to specify many additional errors
that described unspecified parsing behavior in an invalid state).

In addition, remove assertoions from existing tests that suffer from
overspecified errors.

src/jshint.js

@@ -1451,6 +1451,14 @@ var JSHINT = (function () {
       }
     } else {
       error("E030", state.tokens.next, state.tokens.next.value);
+
+      // The token should be consumed after a warning is issued so the parser
+      // can continue as though an identifier were found. The semicolon token
+      // should not be consumed in this way so that the parser interprets it as
+      // a statement delimeter;
+      if (state.tokens.next.id !== ";") {
+        advance();
+      }
     }
   }
 

tests/unit/parser.js

@@ -821,8 +821,6 @@ exports["destructuring var in function scope"] = function (test) {
     .addError(9,  "'a' is already defined.")
     .addError(9,  "'bar' is already defined.")
     .addError(10,  "Expected an identifier and instead saw '1'.")
-    .addError(10,  "Expected ',' and instead saw '1'.")
-    .addError(10,  "Expected an identifier and instead saw ']'.")
     .addError(11, "Expected ',' and instead saw ';'.")
     .addError(11, "'a' is already defined.")
     .addError(11, "'b' is already defined.")
@@ -997,8 +995,6 @@ exports["destructuring var errors"] = function (test) {
 
   TestRun(test)
     .addError(9,  "Expected an identifier and instead saw '1'.")
-    .addError(9,  "Expected ',' and instead saw '1'.")
-    .addError(9,  "Expected an identifier and instead saw ']'.")
     .addError(10, "Expected ',' and instead saw ';'.")
     .addError(11, "Expected ']' to match '[' from line 11 and instead saw ';'.")
     .addError(11, "Missing semicolon.")
@@ -1218,8 +1214,6 @@ exports["destructuring const errors"] = function (test) {
     .addError(2, "const 'b' has already been declared.")
     .addError(2, "const 'c' has already been declared.")
     .addError(3, "Expected an identifier and instead saw '1'.")
-    .addError(3, "Expected ',' and instead saw '1'.")
-    .addError(3, "Expected an identifier and instead saw ']'.")
     .addError(4, "Expected ',' and instead saw ';'.")
     .addError(5, "Expected ']' to match '[' from line 5 and instead saw ';'.")
     .addError(5, "Missing semicolon.")
@@ -3739,6 +3733,14 @@ exports["default arguments in fat arrow functions"] = function (test) {
   test.done();
 };
 
+exports["expressions in place of arrow function parameters"] = function (test) {
+  TestRun(test)
+    .addError(1, "Expected an identifier and instead saw '1'.")
+    .test("(1) => {};", { expr: true, esnext: true });
+
+  test.done();
+};
+
 var conciseMethods = exports.conciseMethods = {};
 
 conciseMethods.basicSupport = function (test) {