ilyalesik / gen-flow-files

Script for transform javascript files to flowtype definition files

gen-flow-files

This is a script which finds .js files with @flow annotation, extract flow definitions and save to specific folder.

As example, <inputDir>/example.js

// @flow

extract function foo(arg1: number, arg2: string): string {
    // some code here
}

will be transformed to <outputDir>/example.js.flow:

// @flow

declare extract function foo(arg1: number, arg2: string): string;

Installation

Install it with yarn:

yarn add gen-flow-files

Or with npm:

npm i gen-flow-files --save

Usage

As part of build process

scripts": {
    ...
    "flow": "flow",
    "build:flow": "gen-flow-files src --out-dir dist",
    ...
  },

transfrom all .js files from src to .js.flow files and save them at dist.

As command

npx gen-flow-files <inputDir> --out-dir <outputDir>

transfrom all .js files from <inputDir> to .js.flow files and save them at <outputDir>.

gen-flow-files's Issues

BUG: error thrown from ClassDeclaration

Issue: When generating .flow.js files the build fails with the following error: TypeError: Property name expected type of string but got null

Steps to reproduce:

1. Try to run gen-flow-files on a Class structured like this:

type ResponseObject = {
  body: mixed,
  callback: () => void,
  error: string,
  statusCode: number,
};

class RandomUtil {
    static RandomUtilReturn({ body, callback, error, statusCode } : ResponseObject) {
...

Expected Result:

• A randomUtil.flow.js file

Actual Result:

• An error
• No files generated

Additional:

• It only happens when a method in the class is using an object spread in the arguments.

Environment:
macOS 10.14.2
node v8.11.3
yarn v1.5.1
flow-bin v^0.94.0
gen-flow-files v^0.4.3

BUG: generation fails

Issue: When running yarn run gen-flow-files src --out-dir lib an error is thrown
Steps to reproduce:

1. Install gen-flow-files via yarn
   2.Run yarn run gen-flow-files src --out-dir lib

Expected behaviour:

• lib folder to contain types extracted from src folder
  Actual behaviour:
• Error in code block below is thrown

Environment:

• macOS 10.14.2
• node v8.11.3
• yarn v1.5.1
• flow-bin v^0.93.0
• gen-flow-files v^0.4.1

Additional:

• I have attempted the build version with node v10, latest version of flow-bin and gen-flow-files
• This was working at last run on a different machine 1 month ago

njm-scripts [master●●] % yarn run gen-flow-files src --out-dir lib
yarn run v1.5.1
$ /Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/.bin/gen-flow-files src --out-dir lib
/Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/@babel/generator/lib/printer.js:277
      throw new ReferenceError(`unknown node of type ${JSON.stringify(node.type)} with constructor ${JSON.stringify(node && node.constructor.name)}`);
      ^

ReferenceError: unknown node of type "Property" with constructor "Node"
    at Generator.print (/Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/@babel/generator/lib/printer.js:277:13)
    at Generator.printJoin (/Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/@babel/generator/lib/printer.js:362:12)
    at Generator.printList (/Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/@babel/generator/lib/printer.js:422:17)
    at Generator.ObjectExpression (/Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/@babel/generator/lib/generators/types.js:69:10)
    at withSource (/Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/@babel/generator/lib/printer.js:299:19)
    at Buffer.withSource (/Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/@babel/generator/lib/buffer.js:185:28)
    at Generator.withSource (/Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/@babel/generator/lib/printer.js:178:15)
    at Generator.print (/Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/@babel/generator/lib/printer.js:298:10)
    at Generator.ExportDeclaration (/Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/@babel/generator/lib/generators/modules.js:114:10)
    at Generator.ExportDefaultDeclaration (/Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/@babel/generator/lib/generators/modules.js:108:21)
error An unexpected error occurred: "Command failed.
Exit code: 1
Command: sh
Arguments: -c /Users/nazimjamil/Sites/njm-test/njm-scripts/node_modules/.bin/gen-flow-files src --out-dir lib
Directory: /Users/nazimjamil/Sites/njm-test/njm-scripts
Output:
".
info If you think this is a bug, please open a bug report with the information provided in "/Users/nazimjamil/Sites/eps/eps-guild/eps-scripts/yarn-error.log".
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

New feature: add ignore option to cli

Example: -i '{**/__tests__/**,**/__integration-tests__/**,**/__fixtures__/**}'

BUG: error thrown from ClassDeclaration when using argument default

Issue: When generating .flow.js files the build fails with the following error: TypeError: Property name expected type of string but got null

Steps to reproduce:

Try to run gen-flow-files on a Class structured like this:

type TitleType = {
  title: 'Mr' | 'Ms' | 'Dr',
};

class TestClass {
    static TestClassFunc(title: TitleType = 'Mr') {
    ...

Expected Result:

• A testClass.flow.js file

Actual Result:

• An error
• No files generated

Additional:

It only happens when a method in the class is using a default in the arguments.
Environment:
macOS 10.14.2
node v8.11.3
yarn v1.5.1
flow-bin v^0.94.0
gen-flow-files v^0.4.4

Use as babel plugin?

Thanks for building this!
I'm trying to bundle all my source code into one single .js.flow file. Is it possible to do so with this project?
I did notice there's a plugin.js file in src. Is it possible to use this project as a babel plugin and achieve my goal?

Would really appreciate any help!