fix(challenges): Fixed import export related challenges

Closes #16235

challenges/02-javascript-algorithms-and-data-structures/es6.json

@@ -827,6 +827,13 @@
         "<hr>",
         "Add the appropriate <code>import</code> statement that will allow the current file to use the <code>capitalizeString</code> function. The file where this function lives is called <code>\"string_functions\"</code>, and it is in the same directory as the current file."
       ],
+      "head": [
+        "window.require = function (str) {",
+        "if (str === 'string_functions') {",
+        "return {",
+        "capitalizeString: str => str.toUpperCase()",
+        "}}};"
+      ],
       "challengeSeed": [
         "\"use strict\";",
         "capitalizeString(\"hello!\");"
@@ -852,6 +859,9 @@
         "<hr>",
         "Below are two variables that I want to make available for other files to use. Utilizing the first way I demonstrated <code>export</code>, export the two variables."
       ],
+      "head": [
+        "window.exports = function(){};"
+      ],
       "challengeSeed": [
         "\"use strict\";",
         "const foo = \"bar\";",
@@ -879,6 +889,14 @@
         "<hr>",
         "The code below requires the contents of a file, <code>\"capitalize_strings\"</code>, found in the same directory as it, imported. Add the appropriate <code>import *</code> statement to the top of the file, using the object provided."
       ],
+      "head": [
+        "window.require = function(str) {",
+        "if (str === 'capitalize_strings') {",
+        "return {",
+        "capitalize: str => str.toUpperCase(),",
+        "lowercase: str => str.toLowerCase()",
+        "}}};"
+      ],
       "challengeSeed": [
         "\"use strict\";",
         "myStringModule.capitalize(\"foo\");",
@@ -904,6 +922,9 @@
         "<hr>",
         "The following function should be the fallback value for the module. Please add the necessary code to do so."
       ],
+      "head": [
+        "window.exports = function(){};"
+      ],
       "challengeSeed": [
         "\"use strict\";",
         "function subtract(x,y) {return x - y;}"
@@ -927,6 +948,13 @@
         "<hr>",
         "In the following code, please import the default export, <code>subtract</code>, from the file <code>\"math_functions\"</code>, found in the same directory as this file."
       ],
+      "head": [
+        "window.require = function(str) {",
+        "if (str === 'math_functions') {",
+          "return function(a, b) {",
+          "return a - b;",
+        "}}};"
+      ],
       "challengeSeed": [
         "\"use strict\";",
         "subtract(7,4);"