tsconfig.json for project with `src` and `tests` : <p>I've got a (desired) structure like this:</p>

<pre><code>- tsconfig.json
- src
    - app.ts
- tests
    - appTest.ts
    - appTest.js
- dist
    - app.js
</code></pre>

<p>If there was no <code>tests</code> folder, a tsconfig.json like this would work fine:</p>

<pre><code>{
    "compilerOptions": {
        "outDir":"dist"
    },
    "include" :[
        "src/**/*.ts"
    ]
}
</code></pre>

<p>However, if I add <code>tests/**/*.ts</code> to the <code>include</code> element, it also compiles my test files into <code>dist</code> and changes its folder structure (understandably, but undesirably).</p>

<p>Can I tell TypeScript compiler to include test files in the project to support things like refactoring but omit them from output to <code>dist</code>? Specifically, I'd like the <code>.js</code> to be compiled in the <code>tests</code> directory as suggested in the structure above.</p>
