Error reported only in node_modules directory

[regseb]

🔎 Search Terms

TS7016, node_modules

🕗 Version & Regression Information

• This is the behavior in every version I tried, and I reviewed the FAQ for entries about node_modules

⏯ Playground Link

No response

💻 Code

.
├─ package.json
├─ index.js
└─ not_node_modules/
   └─ sub/
      ├─ source.js
      └─ type.d.ts

• package.json

  {
    "name": "testcase",
    "version": "1.0.0",
    "devDependencies": {
      "typescript": "5.4.4"
    }
  }

• index.js

  /**
   * @type {import("./node_modules/sub/type.d.ts")}
   */
  const baz = true;
  
  /**
   * @type {import("./not_node_modules/sub/type.d.ts")}
   */
  const qux = true;
  
  // Use variable to remove "'xxx' is declared but its value is never read."
  console.log(baz, qux);

• not_node_modules/

  • not_node_modules/sub/

    • not_node_modules/sub/source.js

      export default {
          BAR: 0,
      };

    • not_node_modules/sub/type.d.ts

      import type Foo from "./source.js";
      
      export type keyofFoo = (typeof Foo)[keyof typeof Foo];
      export default keyofFoo;

1. Unzip testcase.zip
2. cd testcase/
3. npm install
4. cp -r not_node_modules/sub/ node_modules/
5. npx tsc --noEmit --checkJs --strict index.js

🙁 Actual behavior

node_modules/sub/type.d.ts:1:22 - error TS7016: Could not find a declaration file for module './source.js'. '/home/regseb/testcase/node_modules/sub/source.js' implicitly has an 'any' type.

1 import type Foo from "./source.js";
                       ~~~~~~~~~~~~~


Found 1 error in node_modules/sub/type.d.ts:1

🙂 Expected behavior

No error. Or 2 errors with node_modules/sub/type.d.ts and not_node_modules/sub/type.d.ts

Additional information about the issue

The two imported directories (not_node_modules/sub/type.d.ts and node_modules/sub/type.d.ts) are identical, but TypeScript only reports an error for the file in the node_modules directory.

---

I have this problem in my projects. TypeScript doesn't report an error in Metalint (the sub-project). But when I import it into Cast Kodi, TypeScript reports the error.

• metalint
  • level.js (≃ sub/source.js)
  • level.d.ts (≃ sub/type.d.ts)
• castkodi
  • metalint.config.js (≃ index.js)

[andrewbranch]

TypeScript analyzes JavaScript files for type info under allowJs, but this behavior is disabled by default inside node_modules for performance reasons. You can change it via maxNodeModulesJsDepth.

[regseb]

Thanks @andrewbranch for the explanation. There are no more errors with the: npx tsc --noEmit --checkJs --strict index.js --maxNodeModuleJsDepth 2

But I can't ask users of my application to add the maxNodeModuleJsDepth option to their tsconfig.json file. Is there a best practice for this problem?

[typescript-bot]

This issue has been marked as "Working as Intended" and has seen no recent activity. It has been automatically closed for house-keeping purposes.