Add tsdx lint command

[skvale]

• Add tsdx lint command
• Use tsdx lint to lint itself

[jaredpalmer]

Sickkkkk

[jaredpalmer]

This looks great. Will give it try in the morning

[jaredpalmer]

@skvale I think these rules are a bit too tight. Can we just use eslint-config-react-app ?

[skvale]

@jaredpalmer I made createEslintConfig return

{
  extends: ['react-app'],
};

For tsdx, I ran yarn lint --write-file and updated the .eslintrc.js to

module.exports = {
  extends: [
    'react-app',
    'prettier/@typescript-eslint',
    'plugin:prettier/recommended',
  ],
};

We could document the ways of customizing the rules/extensions through

• .eslintrc.js
• packageJson.eslint

in the README

[jaredpalmer]

Since we install prettier for people, we should setup eslint to play nicely? Does eslint config react app do that?

[skvale]

Yep, I'm pretty sure prettier and eslint-config-react-app work well together.

How about adding a --prettier optional flag to lint, like yarn lint --prettier instead of having to generate a .eslintrc.js file or add the rules to the package.json? 4332881

[jaredpalmer]

Run it by default. The less flags the better

[jameslnewell]

🎉Nice!

Can we add a --watch option?

What's the thinking behind providing a separate lint command vs running the linter on build or test? (my DX preference would be to discover and fix linting issues while I'm working in the file where the problems exist rather than having to come back after I've edited a bunch of files - similar to CRA).

[skvale]

Waiting for

• facebook/create-react-app@24489ac
  and
• fix(parser): add simpleTraverse, replaces private ESLint util typescript-eslint/typescript-eslint#628
  to be released to support eslint@6

[jaredpalmer]

Let's resolve conflicts and get this merged?

[skvale]

@jaredpalmer Sounds good
I changed the config to account for facebook/create-react-app@24489ac

and bumped to "@typescript-eslint/parser": "^1.10.3-alpha.13" for the issue from typescript-eslint/typescript-eslint#628

[leohxj]

In vs code, eslint does't lint typescript file by default.Do we need a vscode settings file to make eslint lint ts file?

[leohxj]

does this necessary?
I think use the @typescript-eslint/parser parser is enough.

[skvale]

@leohxj I had to do two things to get eslint to work in vscode. This page for create-react-app explains it well too: https://facebook.github.io/create-react-app/docs/setting-up-your-editor

• tsdx lint --write-file <-- generate the local config file
• Add typescript to my settings file in eslint.validate

  "eslint.validate": [
    "javascript",
    "javascriptreact",
    "typescript",
    "typescriptreact"
  ],

[jaredpalmer]

Is this g2g?

[skvale]

yeah, I think so

[jaredpalmer]

Not for this PR, but we may want to think through some kind of upgrade and/or validation command. This would check package.json, dotfile config, tsconfig, eslint etc. and fill in (and/or reset) any missing pieces. IIRC, jest has something like this called like jest-validate?.