もちろん、あなたはnpm install webpack --save-devを行っていることを前提にしています。これでnpm run build:testなどを実行できます。
この変数を使うのも簡単です:
/**
* This interface makes sure we don't miss adding a property to both `prod` and `test`
*/
interface Config {
someItem: string;
}
/**
* We only export a single thing. The config.
*/
export let config: Config;
/**
* `process.env.NODE_ENV` definition is driven from webpack
*
* The whole `else` block will be removed in the emitted JavaScript
* for a production build
*/
if (process.env.NODE_ENV === 'production') {
config = {
someItem: 'prod'
}
console.log('Running in prod');
} else {
config = {
someItem: 'test'
}
console.log('Running in test');
}