typescript

Typescript application

Full documentation about it here

Tests here are kept next to their code (not in a separate dir). This was done to demonstrate an alternative way of housing tests.

Commands

• npm run compile - compile the ES6 Typescript into the /lib directory
• npm run lint - run the Typescript linter using the tslint.json config file.
• npm test - run the tests using the local .mocharc.json config file. As the config includes the Typescript transpilation hook ts-node/register it does not require pre-compilation before running.

ES Modules

If your typescript project's tsconfig.json has module code generation set to something other than CommonJS, you may encounter an error "SyntaxError: Unexpected token {" when you use an import statement.

import { fail, ok } from 'assert';
       ^

SyntaxError: Unexpected token {
    at Module._compile (internal/modules/cjs/loader.js:721:23)

This is because the underlying ts-node does not support ES modules:

Import Statements Current node.js stable releases do not support ES modules. Additionally, ts-node does not have the required hooks into node.js to support ES modules. You will need to set "module": "commonjs" in your tsconfig.json for your code to work.

See: https://www.npmjs.com/package/ts-node#import-statements

You may need tsconfig.json compiler options for module to be something other than commonjs. You can still set it to commonjs only for testing. The workaround is to set the environment variable TS_NODE_COMPILER_OPTIONS when executing mocha to give ts-node a module setting of commonjs. For example, in package.json:

  "scripts": {
    "test": "env TS_NODE_COMPILER_OPTIONS='{\"module\": \"commonjs\" }' mocha"
  }