Top-level monorepo TypeScript/JavaScript style with tslint and Prettier

...README.md

Goals

• A single style for our projects and others
• Minimize customization - Any decided-upon style is better than one we can bikeshed
• Minimize friction - Instead of warnings, sources are formatted automatically on commit and on save inside your editor
• Minimize files - These three or four files need only be at the top level of the monorepo... nothign in the subdirs

Why X?

• Prettier, no semicolons - Because you don't need them and they add unnecessary visual clutter. Prettier will figure out when they're needed for you.
• Prettier, single quotes - Reduces visual clutter - (Note: Still double quotes for element attributes in JSX/TSX)
• Prettier, 80 chars (the default) - Because you can put more code up side-by-side. It'll be OK. I promise.
• tslint "no-submodule-imports": false - Sometimes you need this in monorepos, especially for testing.
• tslint "object-literal-sort-keys": false - Because sometimes alphanumeric isn't the best way to sort big literals or deconstructions.

.prettierrc

{
  "semi": false,
  "singleQuote": true
}

package.json

{
  "private": true,
  "workspaces": [...],
  "scripts": {
    "lint": "tslint --project .",
    "lint:fix": "tslint --fix --project ."
  },
  "devDependencies": {
    "husky": "1.1.2",
    "lint-staged": "7.3.0",
    "prettier": "1.14.3",
    "tslint": "5.11.0",
    "tslint-config-prettier": "1.15.0",
    "typescript": "^3.1"
  },
  "husky": {
    "hooks": {
      "pre-commit": "lint-staged"
    }
  },
  "lint-staged": {
    "*.{js,json,css,md}": [
      "prettier --write",
      "git add"
    ],
    "*.{ts,tsx}": [
      "tslint --fix",
      "prettier --write --parser=typescript",
      "git add"
    ]
  }
}

tsconfig.json

// This file is optional but might be necessary for TSX/React
{
  "compilerOptions": {
    "target": "esnext",
    "module": "commonjs",
    "jsx": "react",
    "strict": true,
    "resolveJsonModule": true
  },
  "exclude": ["node_modules"]
}

tslint.json

{
  "extends": ["tslint:latest", "tslint-config-prettier"],
  "rules": {
    "interface-name": [true, "never-prefix"],
    "object-literal-sort-keys": false,
    "no-implicit-dependencies": [true, "dev"],
    "no-submodule-imports": false
  },
  "linterOptions": {
    "exclude": [
      "node_modules/**",
      "**/node_modules/**",
      "**/*.d.ts",
      "**/*.json"
    ]
  }
}