title: Circular definition of import alias 'theme'
body: <p>I am trying to extend the theme of a third party private npm module. The project compiles successfully but I keep getting a typescript error <code>Circular definition of import alias 'externalTheme'</code></p>
  <p>Below is how I am extending the theme. This is working perfectly in the way that it is using both my theme and the external theme combined</p>
  <pre><code>import { externalTheme, ExternalThemeInterface } from 'external-npm-repo...'
  
  import { colors, ColorsTypes } from './colors'
  
  export const MyTheme: MyThemeInterface = {
      ...theme,
      colors,
  }
  
  export interface MyThemeInterface extends ExternalThemeInterface {
      colors: ColorsTypes
  }
  </code></pre>
  <p>The error I am getting is referencing circular dependency with the externalTheme import, im not sure what this exactly means and havent found any clear references when researching.</p>
  <p>These are my Typescript settings</p>
  <pre><code>        &quot;allowJs&quot;: true,
          &quot;alwaysStrict&quot;: true,
          &quot;esModuleInterop&quot;: true,
          &quot;forceConsistentCasingInFileNames&quot;: true,
          &quot;isolatedModules&quot;: true,
          &quot;jsx&quot;: &quot;preserve&quot;,
          &quot;lib&quot;: [&quot;dom&quot;, &quot;es2017&quot;],
          &quot;module&quot;: &quot;esnext&quot;,
          &quot;moduleResolution&quot;: &quot;node&quot;,
          &quot;noEmit&quot;: true,
          &quot;noFallthroughCasesInSwitch&quot;: true,
          &quot;noUnusedLocals&quot;: true,
          &quot;noUnusedParameters&quot;: true,
          &quot;resolveJsonModule&quot;: true,
          &quot;skipLibCheck&quot;: true,
          &quot;strict&quot;: true,
          &quot;target&quot;: &quot;esnext&quot;
  </code></pre>