/tslint-devenv

TSLint Development Environment to quickly prototype new rules

MIT LicenseMIT

TSLint Development Environment

I was tired to always tsc lint-rule and check if it compiled, then check if the rule worked as I wanted, not being able to debug the rule itself, so I put some time to setup this small project.

It helps me do the following:

  • Quickly run new rules on an existing project
  • No additional dependencies on the new project
  • Debugging the execution of the rule in typescript with node --inspect
  • It is not required to add the rule to the base repository while testing

Setup

  • clone this repository next to your actual project
  • npm i on this repository
  • code the new rule e. g. as src/someAwesomeRule.ts
  • test-run & debug the rule
  • build the rule and include it in your project

There are several possibilities to run the rule, e. g. using a file watcher like nodemon to automatically rerun when the files change, I prefer the following setup to debug from VSCode

VSCode launch.json

  • Open new rule file, without leaving current workspace (e. g. ../tslint-devenv/src/someAwesomeRule.ts)
  • Add the following to launch.json: 
    {
  "type": "node",
  "request": "launch",
  "name": "tslint-env",
  "port": 9299,
  "cwd": "${workspaceFolder}/../tslint-devenv",
  "runtimeArgs": [
    "--inspect-brk=9299",
    "-r",
    "ts-node/register",
  ],
  "args": [
    "-p",
    "${workspaceFolder}/tsconfig.json",
    "-r",
    "src",
  ],
  "program": "${workspaceFolder}/../tslint-devenv/node_modules/.bin/tslint",
  "sourceMaps": true,
  "console": "integratedTerminal"
}

Call every time from terminal

Another possibility would be to run the command using nodemon. The tricky part is to pass in -p path/to/your/project and -r src-folder/with/the/rule to tslint while also calling node --inspect-brk -r ts-node/register to enable debugging, so at least in this command both the repositories have to be referenced. A full one-time command could look like this:
Calling from tslint-devenv

node --inspect-brk -r ts-node-register node_modules/.bin/tslint -r src -p ../my-project/tsconfig.json

Calling from your project

node --inspect-brk -r ts-node-register ../tslint-devenv/node_modules/.bin/tslint -r ../tslint-devenv/src -p tsconfig.json

Use the rules in your project

Once the rule is finished, run npm run build and copy the compiled JavaScript file from dist to your project's rule folder. Do not forget to add the new rule name and the folder containing your custom rules to your tslint.json.