Add TypeScript support

Author: jhnns

lib/moduleEnv.js

@@ -84,22 +84,30 @@ function requireProxy(path) {
 
 function registerExtensions() {
     var originalJsExtension = require.extensions[".js"];
+    var originalTsExtension = require.extensions[".ts"];
     var originalCoffeeExtension = require.extensions[".coffee"];
 
     if (originalJsExtension) {
         originalExtensions.js = originalJsExtension;
     }
+    if (originalTsExtension) {
+        originalExtensions.ts = originalTsExtension;
+    }
     if (originalCoffeeExtension) {
         originalExtensions.coffee = originalCoffeeExtension;
     }
     require.extensions[".js"] = jsExtension;
+    require.extensions[".ts"] = tsExtension;
     require.extensions[".coffee"] = coffeeExtension;
 }
 
 function restoreExtensions() {
     if ("js" in originalExtensions) {
         require.extensions[".js"] = originalExtensions.js;
     }
+    if ("ts" in originalExtensions) {
+        require.extensions[".ts"] = originalExtensions.ts;
+    }
     if ("coffee" in originalExtensions) {
         require.extensions[".coffee"] = originalExtensions.coffee;
     }
@@ -136,6 +144,32 @@ function jsExtension(module, filename) {
     originalExtensions.js(module, filename);
 }
 
+function tsExtension(module, filename) {
+    var _compile = module._compile;
+
+    module._compile = function rewireCompile(content, filename) {
+        var noConstAssignMessage = linter.verify(content, eslintOptions).find(isNoConstAssignMessage);
+        var line;
+        var column;
+
+        if (noConstAssignMessage !== undefined) {
+            line = noConstAssignMessage.line;
+            column = noConstAssignMessage.column;
+            throw new TypeError(`Assignment to constant variable at ${ filename }:${ line }:${ column }`);
+        }
+        _compile.call(
+            this,
+            content
+                .replace(shebang, '') // Remove shebang declarations
+                .replace(matchConst, "$1let  $2"), // replace const with let, while maintaining the column width
+            filename
+        );
+    };
+
+    restoreExtensions();
+    originalExtensions.ts(module, filename);
+}
+
 function coffeeExtension(module, filename) {
     if (!coffee) {
         throw new Error("Cannot rewire module written in CoffeeScript: Please install 'coffeescript' package first.");