Typescript Types Incorrect

[beardedtim]

Issue

When I install json-schema-faker and try to use it in my code, the types seem to be different than the values exported. Specifically, the types say there is an object called JSONSchemaFaker that can be imported and has all of the available methods. However, when trying to use the values the JS runtime says it is undefined.

Repro Steps

Below are the CLI commands ran before trying to execute the code

 npm init -y
 npm i -D typescript ts-node

npx tsc -init

npm i json-schema-faker @faker-js/faker chance
npm i -D @types/chance

You can create two files and try to run them both to see the output

This prints undefined when I would expect something

import { JSONSchemaFaker } from "json-schema-faker";

const main = () => {
  console.log(JSONSchemaFaker, "What is the value printed here when imported?");
};

main();

This prints something when I would expect nothing

import * as JSF from "json-schema-faker";

const main = () => {
  console.log(JSF, "What is the value printed here when imported?");
};

main();

Screenshots

You can see that the Typescript types show that the import that prints undefined should have methods attached.

while importing the thing that prints something shows that the only thing that should be on the object is the exported JSONSchemaFaker

Settings

Here are the node and npm versions currently being used

node -v 
v16.17.1

npm -v
8.15.0

[pateketrueke]

Yeah, definitely I did not ensure the published module would work, sorry for the inconvenience!

As a temporary workaround, you can import the module from json-schema-faker/dist/main.mjs instead.

I'll be releasing a patched version asap, just I need to figure out what happened, thank you. 🙏🏽

[pateketrueke]

@pmcelhaney I've pushed a fix for this on the develop branch, tests are passing and I ran a few integrations too both with cjs/esm files, can you help me to validate if types are still correct? Thank you!

[pateketrueke]

@pmcelhaney I had to force a push for the same branch, now also the IIFE/UMD tests are working!

[pmcelhaney]

Looks good!

import { default as jsf, JSONSchemaFaker } from "json-schema-faker";

// should be deprecated; it is
jsf(); 

// should not be callable; it's not
JSONSchemaFaker(); 


// should have autocomplete and type check; it does
JSONSchemaFaker.VERSION; 
JSONSchemaFaker.generate({});
// ... 

@beardedtim thanks for the report and easy to follow test case!

[pmcelhaney]

Wait, after that force push I don't think it's right

[pmcelhaney]

Never mind, it's still good. :)

[pateketrueke]

Fine, I am publishing it right now, carefully to avoid mistakes again! 🍻

[pateketrueke]

@beardedtim finally it's published and ready for your usage, so much thanks for your immediate feedback!

[beardedtim]

Thank you so much for the quick turn around and fix @pateketrueke . Greatly appreciate the work and the repo!

[yoeran]

Looks like something reverted maybe? I'm experiencing this same issue at the moment, when upgrading to 0.5.3.

[pateketrueke]

@yoeran can you describe your issue? thank you!

[yoeran]

After upgrading json-schema-faker from 0.5.0-rcv.42 to 0.5.3 our pipelines started failing because the default export no longer works. So I've refactored all occurrences from:

import jsf from 'json-schema-faker';

to

import { JSONSchemaFaker } from 'json-schema-faker';

Which shows no errors in VSCode, but in testing and pipeline I get the following error:

TypeError: Cannot read properties of undefined (reading 'JSONSchemaFaker')

      46 | });
      47 |
    > 48 | JSONSchemaFaker.format('dateRange', () =>
         | ^

Notice, that it doesn't say "cannot read format of undefined", but reading JSONSchemaFaker of undefined. Never seen that before.

[pateketrueke]

@yoeran I see, the thing is a two-steps check:

1. vscode checks the typescript, if you hover the method you'll see the definitions, etc. if that's true, then it means the typescript definitions are correct
2. your pipeline bundles your code, and is not related with typescript anymore, but rather of the tooling you're using for running it

Can you tell us if (1) is working for you, and then if (2) doe not, what are you using as your pipeline?

[yoeran]

@pateketrueke I understand.

1. Yes, the typescript definitions are correct.
2. We use RushJS for all tooling. So pnpm as package manager and Jest for running tests. The errors occurs in both the Github pipeline and locally when running tests via npm test.

[pateketrueke]

@yoeran ok, I don't know how that tooling works but it would be using a bundler under the hood, bundlers have settings for resolving modules. Probably is not resolving correctly the module version (which is preferred) of this package. Please make sure it understands the "exports" from the package.json definition.