Add transpileOnly flag, default to typeCheck

README.md

@@ -11,8 +11,6 @@
 
 ```sh
 npm install -g ts-node
-
-# Install a TypeScript compiler (requires `typescript` by default).
 npm install -g typescript
 ```
 
@@ -24,15 +22,13 @@ npm install -g typescript
 * Source map support
 * Loads compiler options from `tsconfig.json`
 
-**Important:** The default mode of `ts-node` is transpile _without_ type checking. This can cause problems where type information is required to generate a valid JavaScript program. Two known examples of this are `const enum` and import elision of type files used in valid runtime positions. If you require these features, ensure you enable type checking.
-
 ## Usage
 
 ```sh
-# Execute a script as you would normally with `node`.
+# Execute a script as `node` + `tsc`.
 ts-node script.ts
 
-# Starts the TypeScript REPL.
+# Starts a TypeScript REPL.
 ts-node
 
 # Execute code with TypeScript.
@@ -49,7 +45,7 @@ echo "console.log('Hello, world!')" | ts-node
 
 ### Programmatic
 
-You can require `ts-node` and register the loader for future requires by using `require('ts-node').register({ /* options */ })`. You can also use the shortcuts `node -r ts-node/register` or `node -r ts-node/register/type-check` depending on your preferences.
+You can require `ts-node` and register the loader for future requires by using `require('ts-node').register({ /* options */ })`. You can also use file shortcuts - `node -r ts-node/register` or `node -r ts-node/register/transpile-only` - depending on your preferences.
 
 **Note:** If you need to use advanced node.js CLI arguments (e.g. `--inspect`), use them with `node -r ts-node/register` instead of the `ts-node` CLI.
 
@@ -95,7 +91,7 @@ Create a new node.js configuration, add `-r ts-node/register` to node args and m
 
 ## How It Works
 
-**TypeScript Node** works by registering the TypeScript compiler for the `.ts`, `.tsx` and, with `allowJs` enabled, `.js` extensions. When node.js has a file extension registered (the `require.extensions` object), it will use the extension internally for module resolution. When an extension is unknown to node.js, it will handle the file as `.js` (JavaScript).
+**TypeScript Node** works by registering the TypeScript compiler for `.tsx?` and `.jsx?` extension (when `allowJs == true`). When node.js has an extension registered (via `require.extensions`), it will use the extension internally for module resolution. When an extension is unknown to node.js, it handles the file as `.js` (JavaScript).
 
 **P.S.** This means if you don't register an extension, it is compiled as JavaScript. When `ts-node` is used with `allowJs`, JavaScript files are transpiled using the TypeScript compiler.
 
@@ -124,7 +120,7 @@ Supports `--print`, `--eval` and `--require` from [node.js CLI options](https://
 
 _Environment variable denoted in parentheses._
 
-* `--typeCheck` Enable type checking for TypeScript (`TS_NODE_TYPE_CHECK`)
+* `--transpileOnly` Use TypeScript's faster `transpileModule` (`TS_NODE_TRANSPILE_ONLY`)
 * `--cacheDirectory` Configure the output file cache directory (`TS_NODE_CACHE_DIRECTORY`)
 * `-I, --ignore [pattern]` Override the path patterns to skip compilation (`TS_NODE_IGNORE`)
 * `-P, --project [path]` Path to TypeScript JSON project file (`TS_NODE_PROJECT`)
@@ -143,9 +139,9 @@ _Environment variable denoted in parentheses._
 
 ## Watching and Restarting
 
-**TypeScript Node** only compiles source code on the fly, watching files and code reloads are out of scope. If you want to restart the `ts-node` process on file changes, standard node.js tools exist already such as [nodemon](https://github.com/remy/nodemon), [onchange](https://github.com/Qard/onchange) and [node-dev](https://github.com/fgnass/node-dev). 
+**TypeScript Node** compiles source code via `require()`, watching files and code reloads are out of scope for the project. If you want to restart the `ts-node` process on file change, existing node.js tools such as [nodemon](https://github.com/remy/nodemon), [onchange](https://github.com/Qard/onchange) and [node-dev](https://github.com/fgnass/node-dev) work.
 
-There is also [`ts-node-dev`](https://github.com/whitecolor/ts-node-dev), a modified version of [`node-dev`](https://github.com/fgnass/node-dev) that uses `ts-node` for compilation and doesn't restart the process on every change.
+There's also [`ts-node-dev`](https://github.com/whitecolor/ts-node-dev), a modified version of [`node-dev`](https://github.com/fgnass/node-dev) using `ts-node` for compilation and won't restart the process on file change.
 
 ## License
 

register/transpile-only.js

@@ -0,0 +1,3 @@
+require('../').register({
+  transpileOnly: true
+})

src/bin.ts

@@ -22,6 +22,7 @@ interface Argv {
   version?: boolean
   // Register options.
   typeCheck?: boolean
+  transpileOnly?: boolean
   cache?: boolean
   cacheDirectory?: string
   compiler?: string
@@ -37,14 +38,15 @@ interface Argv {
 const argv = minimist<Argv>(process.argv.slice(2), {
   stopEarly: true,
   string: ['eval', 'print', 'compiler', 'project', 'ignoreDiagnostics', 'require', 'cacheDirectory', 'ignore'],
-  boolean: ['help', 'typeCheck', 'version', 'cache', 'skipProject', 'skipIgnore'],
+  boolean: ['help', 'transpileOnly', 'typeCheck', 'version', 'cache', 'skipProject', 'skipIgnore'],
   alias: {
     eval: ['e'],
     print: ['p'],
     require: ['r'],
     help: ['h'],
     version: ['v'],
     typeCheck: ['type-check'],
+    transpileOnly: ['transpile-only'],
     cacheDirectory: ['cache-directory'],
     ignore: ['I'],
     project: ['P'],
@@ -57,6 +59,7 @@ const argv = minimist<Argv>(process.argv.slice(2), {
   default: {
     cache: DEFAULTS.cache,
     typeCheck: DEFAULTS.typeCheck,
+    transpileOnly: DEFAULTS.transpileOnly,
     skipIgnore: DEFAULTS.skipIgnore,
     skipProject: DEFAULTS.skipProject
   }
@@ -75,7 +78,7 @@ Options:
   -h, --help                     Print CLI usage
   -v, --version                  Print module version information
 
-  --type-check                   Enable type checking through CLI
+  -T, --transpile-only           Use TypeScript's faster \`transpileModule\`
   --cache-directory              Configure the output file cache directory
   -I, --ignore [pattern]         Override the path patterns to skip compilation
   -P, --project [path]           Path to TypeScript JSON project file
@@ -84,8 +87,8 @@ Options:
   -O, --compilerOptions [opts]   JSON object to merge with compiler options
 
   --no-cache                     Disable the local TypeScript Node cache
-  --skip-project                 Skip project config resolution and loading
-  --skip-ignore                  Skip ignore checks
+  --skip-project                 Skip reading \`tsconfig.json\`
+  --skip-ignore                  Skip \`--ignore\` checks
 `)
 
   process.exit(0)
@@ -99,6 +102,7 @@ const isPrinted = argv.print !== undefined
 // Register the TypeScript compiler instance.
 const service = register({
   typeCheck: argv.typeCheck,
+  transpileOnly: argv.transpileOnly,
   cache: argv.cache,
   cacheDirectory: argv.cacheDirectory,
   ignore: argv.ignore,

src/index.spec.ts

@@ -107,7 +107,7 @@ describe('ts-node', function () {
     })
 
     it('should throw errors', function (done) {
-      exec(`${BIN_EXEC} --typeCheck -e "import * as m from './tests/module';console.log(m.example(123))"`, function (err) {
+      exec(`${BIN_EXEC} -e "import * as m from './tests/module';console.log(m.example(123))"`, function (err) {
         if (err === null) {
           return done('Command was expected to fail, but it succeeded.')
         }
@@ -124,7 +124,7 @@ describe('ts-node', function () {
 
     it('should be able to ignore diagnostic', function (done) {
       exec(
-        `${BIN_EXEC} --type-check --ignoreDiagnostics 2345 -e "import * as m from './tests/module';console.log(m.example(123))"`,
+        `${BIN_EXEC} --ignoreDiagnostics 2345 -e "import * as m from './tests/module';console.log(m.example(123))"`,
         function (err) {
           if (err === null) {
             return done('Command was expected to fail, but it succeeded.')
@@ -140,7 +140,7 @@ describe('ts-node', function () {
     })
 
     it('should work with source maps', function (done) {
-      exec(`${BIN_EXEC} --type-check tests/throw`, function (err) {
+      exec(`${BIN_EXEC} tests/throw`, function (err) {
         if (err === null) {
           return done('Command was expected to fail, but it succeeded.')
         }
@@ -157,7 +157,7 @@ describe('ts-node', function () {
     })
 
     it.skip('eval should work with source maps', function (done) {
-      exec(`${BIN_EXEC} --type-check -p "import './tests/throw'"`, function (err) {
+      exec(`${BIN_EXEC} -p "import './tests/throw'"`, function (err) {
         if (err === null) {
           return done('Command was expected to fail, but it succeeded.')
         }
@@ -172,8 +172,8 @@ describe('ts-node', function () {
       })
     })
 
-    it('should use transpile mode by default', function (done) {
-      exec(`${BIN_EXEC} -p "x"`, function (err) {
+    it('should support transpile only mode', function (done) {
+      exec(`${BIN_EXEC} --transpileOnly -p "x"`, function (err) {
         if (err === null) {
           return done('Command was expected to fail, but it succeeded.')
         }

src/index.ts

@@ -52,6 +52,7 @@ export const VERSION = pkg.version
  */
 export interface Options {
   typeCheck?: boolean | null
+  transpileOnly?: boolean | null
   cache?: boolean | null
   cacheDirectory?: string
   compiler?: string
@@ -96,7 +97,8 @@ export const DEFAULTS: Options = {
   skipIgnore: yn(process.env['TS_NODE_SKIP_IGNORE']),
   skipProject: yn(process.env['TS_NODE_SKIP_PROJECT']),
   ignoreDiagnostics: split(process.env['TS_NODE_IGNORE_DIAGNOSTICS']),
-  typeCheck: yn(process.env['TS_NODE_TYPE_CHECK'])
+  typeCheck: yn(process.env['TS_NODE_TYPE_CHECK']),
+  transpileOnly: yn(process.env['TS_NODE_TRANSPILE_ONLY'])
 }
 
 /**
@@ -201,7 +203,7 @@ export function register (opts: Options = {}): Register {
   // Require the TypeScript compiler and configuration.
   const cwd = process.cwd()
   const compiler = options.compiler || 'typescript'
-  const typeCheck = options.typeCheck || false
+  const typeCheck = options.typeCheck === true || options.transpileOnly !== true
   const ts: typeof TS = require(compiler)
   const transformers = options.transformers || undefined
   const readFile = options.readFile || ts.sys.readFile