Add support for --require flag like node CLI (#181)

Author: blakeembrey

custom_typings/node.d.ts

@@ -9,12 +9,17 @@ declare module 'module' {
     static runMain (): void
     static wrap (code: string): string
     static _nodeModulePaths (path: string): string[]
+    static _load (request: string, parent?: Module, isMain?: boolean): any
+    static _resolveFilename (request: string, parent?: Module, isMain?: boolean): string
+    static _extensions: { [ext: string]: (m: Module, fileName: string) => any }
 
-    constructor (filename: string)
+    constructor (filename: string, parent?: Module)
 
+    parent: Module
     filename: string
     paths: string[]
     exports: any
+    loaded: boolean
     require (module: string): any
   }
 

src/_bin.ts

@@ -21,13 +21,14 @@ interface Argv {
   help?: boolean
   compiler?: string
   project?: string
+  require?: string | string[]
   ignoreWarnings?: string | string[]
   disableWarnings?: boolean
   compilerOptions?: any
   _: string[]
 }
 
-const strings = ['eval', 'print', 'compiler', 'project', 'ignoreWarnings', 'cacheDirectory']
+const strings = ['eval', 'print', 'compiler', 'project', 'ignoreWarnings', 'require', 'cacheDirectory']
 const booleans = ['help', 'fast', 'lazy', 'version', 'disableWarnings', 'cache']
 
 const aliases: { [key: string]: string[] } = {
@@ -39,6 +40,7 @@ const aliases: { [key: string]: string[] } = {
   print: ['p'],
   project: ['P'],
   compiler: ['C'],
+  require: ['r'],
   cacheDirectory: ['cache-directory'],
   ignoreWarnings: ['I', 'ignore-warnings'],
   disableWarnings: ['D', 'disable-warnings'],
@@ -119,6 +121,7 @@ Options:
 
   -e, --eval [code]             Evaluate code
   -p, --print [code]            Evaluate code and print result
+  -r, --require [path]          Require a node module for execution
   -C, --compiler [name]         Specify a custom TypeScript compiler
   -I, --ignoreWarnings [code]   Ignore TypeScript warnings by diagnostic code
   -D, --disableWarnings         Ignore every TypeScript warning
@@ -167,6 +170,12 @@ const EVAL_PATH = join(cwd, EVAL_FILENAME)
 // Store eval contents for in-memory lookups.
 const evalFile = { input: '', output: '', version: 0 }
 
+// Require specified modules before start-up.
+for (const id of arrify(argv.require)) {
+  Module._load(id)
+}
+
+// Execute the main contents (either eval, script or piped).
 if (isEvalScript) {
   evalAndExit(code, isPrinted)
 } else {

src/index.spec.ts

@@ -158,6 +158,15 @@ describe('ts-node', function () {
         return done()
       })
     })
+
+    it('should support require flags', function (done) {
+      exec(`${BIN_EXEC} -r ./tests/hello-world -p "console.log('success')"`, function (err, stdout) {
+        expect(err).to.not.exist
+        expect(stdout).to.equal('Hello, world!\nsuccess\nundefined\n')
+
+        return done()
+      })
+    })
   })
 
   describe('register', function () {