starter config for TS CRA on Github

.eslintignore

# Ignore everything:
/*

# Except src:
!/src

.eslintrc.json

{
  "extends": ["react-app", "eslint:recommended"],
  "rules": {
    "default-case": "error",
    "default-case-last": "error",
    "default-param-last": "error",
    "eqeqeq": "error",
    "no-alert": "warn",
    "no-console": "warn",
    "no-magic-numbers": "warn",
    "no-redeclare": "off", // original no-redeclare rule must be turned off as it can return in correct errors, see https://github.com/typescript-eslint/typescript-eslint/blob/master/packages/eslint-plugin/docs/rules/no-redeclare.md
    "@typescript-eslint/no-redeclare": "error",
    "no-self-compare": "error",
    "no-shadow": "warn",
    "no-unreachable-loop": "warn",
    "no-unsafe-optional-chaining": "error",
    "no-unused-expressions": "warn",
    "no-unused-vars": "warn",
    "no-useless-return": "error",
    "require-await": "error",
    "yoda": "error"
  }
}

.githubSLASHworkflowsSLASHmain.yaml

name: CI

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  test:
    runs-on: ubuntu-latest

    steps:
      - name: Setup Node.js
        uses: actions/setup-node@v1
        with:
          node-version: 12

      - name: Checkout repository
        uses: actions/checkout@v2

      - name: Install dependencies
        run: npm install

      - name: Run jest tests
        run: npm run test

      - name: Check for build errors
        run: npm run build

.prettierignore

# Ignore everything:
/*

# Except src:
!/src

.prettierrc.json

{
  "printWidth": 100,
  "trailingComma": "all",
  "tabWidth": 2,
  "useTabs": false,
  "semi": true,
  "singleQuote": true,
  "quoteProps": "as-needed",
  "jsxSingleQuote": false,
  "bracketSpacing": true,
  "jsxBracketSameLine": false,
  "arrowParens": "always",
  "proseWrap": "always",
  "htmlWhitespaceSensitivity": "css",
  "endOfLine": "lf"
}

dependencies.bash

# need a specific version of husky to avoid an issue with prettier (i've forgotted what the error was)
yarn add --dev [email protected] prettier pretty-quick

package.json

// add this pre-commit hook to the rest of the file
"husky": {
  "hooks": {
    "pre-commit": "pretty-quick --staged"
  }
}

tsconfig.json

{
  "compilerOptions": {
    "baseUrl": "src",
    "target": "es5",
    "lib": ["dom", "dom.iterable", "esnext"],
    "allowJs": true,
    "skipLibCheck": true,
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true,
    "strict": true,
    "forceConsistentCasingInFileNames": true,
    "noFallthroughCasesInSwitch": true,
    "module": "esnext",
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "isolatedModules": true,
    "noEmit": true,
    // this might need to be "jsx": "react" if it isn't the latest CRA where you don't need to import React
    "jsx": "react-jsx",
    "noImplicitAny": true
  },
  "include": ["src/**/*.ts"]
}