TypeScript module versions conflicts

[imt-jaime]

TypeScript Version: 3.4.0-dev.201xxxxx

Search Terms:

types conflict
modules conflict ts(2742)
duplicate modules
module versions conflict
monorepo modules conflict

Code

index.ts (main project)

import { moduleB } from 'ts-issue-module-b';
// import { SomeInterface } from 'ts-typelib-example'; // this line makes no sense

const valueB = moduleB(3); // <---- error ts(2742)

export {
  valueB
}

ts-module-b (linked package module)

import { SomeInterface } from 'ts-typelib-example';
import { moduleA } from 'ts-issue-module-a';

export const moduleB = (age: number): SomeInterface => {
  const data = moduleA(age.toString())
  const ageString = data.age;

  const value: SomeInterface = {
    age: parseInt(ageString, 10)
  }
  
  return value;
}

ts-module-a (module-b dependency)

import { SomeInterface } from 'ts-typelib-example';

export const moduleA = (age: string): SomeInterface => {
  const value: SomeInterface = {
    age
  };

  return value;
}

For SomeInterface it exists in 2 versions: (1.0.0) where age is a string and (2.0.0) where age is a number. (breaking change version.

Expected behavior:

The expected behaviour is that the returned interface by moduleB should be the 2.0.0 version interface (as expected from node_modules resolution first level). Instead, VSCode displays an error telling to import SomeInterface to resolve the conflict.

Actual behavior:

TypeScript cannot resolve the type returned by the moduleB function creating undesirable errors in dependencies. (This error could exist in thousands of dependencies due to developers cant update 2nd level dependencies from third party modules).

Playground Link:

https://github.com/imt-jaime/ts-monorepo-issue-example

Related Issues:

#29221

** Repository Structure **

• node_modules
  • module-b (linked)
• src
  • index.js
  • packages
    • module-b (linked globally)
      • node_modules
        • ts-typelib-example (v2.0.0)
        • module-a
          • node_modules
            • ts-typelib-example (v1.0.0)
          • src
          • package.json
      • src
      • package.json
    • ts-typelib-example
      • node_modules
      • src
      • package.json
• package.json

More information can be found in the repository (README.md)

[imt-jaime]

I've still having problems with TypeScript and types resolution, not only with monorepositories: As i said, npm allows to install more than one breaking change version installed (usually the older one is installed in specific modules and newer in node_modules root) and TypeScript stills having problems with modified types and interfaces.

This problem could be extended to all the community in the future due to not all developers have the most recent version of all modules. As more typescript modules you have installed the risk is increased due to more version modules exists in your node modules. The issue seems to be also related to this commit #33567.

While using "traceResolution" option in compiler options, node resolution behavior seems to be right, it goes from the file to the project root looking for on each iteration "./node_modules/module" but, somehow types are like "stored" in a paths cache which confuses module folders. I've seen sometimes VSCode telling that there are multiple matches with a module absolute import path (Maybe should select the closest one).

[sheetalkamat]

@imt-jaime Can you please update your repro and see if it still repros.. I followed exact steps in your repro and I get completely different error:

Here are the steps I followed:

• Clone the repo
• cd src\packages\ts-issue-module-b
• npm link
• cd cd ......\
• npm link ts-issue-module-b
• tsc

src/index.ts:4:7 - error TS2742: The inferred type of 'valueB' cannot be named without a reference to 'ts-issue-module-b/node_modules/ts-typelib-example'. This is likely not portable. A type annotation is necessary.

4 const valueB = moduleB(3);
        ~~~~~~

src/packages/ts-issue-module-a/src/index.ts:1:31 - error TS2307: Cannot find module 'ts-typelib-example'.

1 import { SomeInterface } from 'ts-typelib-example';
                                ~~~~~~~~~~~~~~~~~~~~


Found 2 errors.

[imt-jaime]

Hello @sheetalkamat , i've updated the repository to version 3.7.5 (current) and it stills happening.

The steps to reproduce the issue were the same except for the last one (npm run typescript which is tsc command). However the error ive found is different from yours, it seems link didn't installed module-b dependencies. Maybe you missed to install project dependencies? (npm install at root)

Correction:
(confirmed, i've got your error when base project has no installed dependencies) I've updated repository instructions. However this error is also unexplained due to 'ts-typelib-example' is also installed in 'ts-issue-module-b' .
Doesn't compiler looks inside the closest node_modules when "moduleResolution": "node" is specified?.

Thats the error I get by running typescript:

src/packages/ts-issue-module-a/src/index.ts:5:5 - error TS2322: Type 'string' is not assignable to type 'number'.

5     age
      ~~~

  node_modules/ts-issue-module-b/node_modules/ts-typelib-example/src/index.ts:2:3
    2   age: number;
        ~~~
    The expected type comes from property 'age' which is declared here on type 'SomeInterface'


Found 1 error.

Additional Information:

Working in another projects stills the same error, I think typescript creates a libraries cache like and selects randomly what library to check avoiding node_resolution without taking care of versions or node_modules structure.

[imt-jaime]

The error displayed by VSCode: