add out of bounds check to default parameter template - addresses #1845 - cc @RReverser

src/babel/transformation/templates/default-parameter.js

@@ -1 +1 @@
-let VARIABLE_NAME = ARGUMENTS[ARGUMENT_KEY] === undefined ? DEFAULT_VALUE : ARGUMENTS[ARGUMENT_KEY];
+let VARIABLE_NAME = ARGUMENTS.length >= ARGUMENT_KEY && ARGUMENTS[ARGUMENT_KEY] === undefined ? DEFAULT_VALUE : ARGUMENTS[ARGUMENT_KEY];

test/core/fixtures/transformation/es6.arrow-functions/default-parameters/expected.js

@@ -1,9 +1,9 @@
 "use strict";
 
 var some = function some() {
-  var count = arguments[0] === undefined ? "30" : arguments[0];
+  var count = arguments.length >= 0 && arguments[0] === undefined ? "30" : arguments[0];
 
   console.log("count", count);
 };
 
-some();
+some();

test/core/fixtures/transformation/es6.parameters/default-eval/expected.js

@@ -2,7 +2,7 @@
 
 var x = "outside";
 function outer() {
-  var a = arguments[0] === undefined ? function () {
+  var a = arguments.length >= 0 && arguments[0] === undefined ? function () {
     return eval("x");
   } : arguments[0];
   return (function () {
@@ -10,4 +10,4 @@ function outer() {
     return a();
   })();
 }
-outer();
+outer();

test/core/fixtures/transformation/es6.parameters/default-multiple/expected.js

@@ -1,14 +1,14 @@
 "use strict";
 
 var t = function t() {
-  var e = arguments[0] === undefined ? "foo" : arguments[0];
+  var e = arguments.length >= 0 && arguments[0] === undefined ? "foo" : arguments[0];
-  var f = arguments[1] === undefined ? 5 : arguments[1];
+  var f = arguments.length >= 1 && arguments[1] === undefined ? 5 : arguments[1];
 
   return e + " bar " + f;
 };
 
 var a = function a(e) {
-  var f = arguments[1] === undefined ? 5 : arguments[1];
+  var f = arguments.length >= 1 && arguments[1] === undefined ? 5 : arguments[1];
 
   return e + " bar " + f;
-};
+};

test/core/fixtures/transformation/es6.parameters/default-single/expected.js

@@ -1,7 +1,7 @@
 "use strict";
 
 var t = function t() {
-  var f = arguments[0] === undefined ? "foo" : arguments[0];
+  var f = arguments.length >= 0 && arguments[0] === undefined ? "foo" : arguments[0];
 
   return f + " bar";
-};
+};

test/core/fixtures/transformation/es6.tail-call/default-parameters/expected.js

@@ -6,9 +6,9 @@ function sum() {
 
   _function: while (_again) {
     a = b = undefined;
-    var a = _arguments[0] === undefined ? 1 : _arguments[0];
+    var a = _arguments.length >= 0 && _arguments[0] === undefined ? 1 : _arguments[0];
     _again = false;
-    var b = _arguments[1] === undefined ? 2 : _arguments[1];
+    var b = _arguments.length >= 1 && _arguments[1] === undefined ? 2 : _arguments[1];
 
     if (b > 0) {
       _arguments = [a + 1, b - 1];
@@ -17,4 +17,4 @@ function sum() {
     }
     return a;
   }
-}
+}

test/core/fixtures/transformation/es6.tail-call/factorial/expected.js

@@ -8,7 +8,7 @@ function fact(_x2) {
     var n = _x2;
     acc = undefined;
     _again = false;
-    var acc = _arguments[1] === undefined ? 1 : _arguments[1];
+    var acc = _arguments.length >= 1 && _arguments[1] === undefined ? 1 : _arguments[1];
     if (n > 1) {
       _arguments = [_x2 = n - 1, acc * n];
       _again = true;
@@ -17,4 +17,4 @@ function fact(_x2) {
       return acc;
     }
   }
-}
+}

test/core/fixtures/transformation/es6.tail-call/max-args/expected.js

@@ -7,7 +7,7 @@ var count = function count() {
   _function: while (_again) {
     i = undefined;
     _again = false;
-    var i = _arguments[0] === undefined ? 10 : _arguments[0];
+    var i = _arguments.length >= 0 && _arguments[0] === undefined ? 10 : _arguments[0];
 
     if (!i) return;
     _arguments = [i - 1];
@@ -23,11 +23,11 @@ function count2() {
   _function2: while (_again2) {
     i = undefined;
     _again2 = false;
-    var i = _arguments2[0] === undefined ? 10 : _arguments2[0];
+    var i = _arguments2.length >= 0 && _arguments2[0] === undefined ? 10 : _arguments2[0];
 
     if (!i) return;
     _arguments2 = [i - 1];
     _again2 = true;
     continue _function2;
   }
-}
+}

test/core/fixtures/transformation/es6.tail-call/recursion/expected.js

@@ -11,7 +11,7 @@
     var g = function g() {};
 
     _again = false;
-    var m = _arguments[1] === undefined ? getDefaultValue() : _arguments[1];
+    var m = _arguments.length >= 1 && _arguments[1] === undefined ? getDefaultValue() : _arguments[1];
 
     // `m` should be `getDefaultValue()` after first pass
     if (n <= 0) {
@@ -27,4 +27,4 @@
     _again = true;
     continue _function;
   }
-})(1e6, true) === "foo";
+})(1e6, true) === "foo";

test/core/fixtures/transformation/misc/regression-1168/expected.js

@@ -1,7 +1,7 @@
 "use strict";
 
 function test() {
-  var x = arguments[0] === undefined ? "hi" : arguments[0];
+  var x = arguments.length >= 0 && arguments[0] === undefined ? "hi" : arguments[0];
 
   return x;
-}
+}