From ESLint and Prettier to Biome

{
  // See: https://biomejs.dev/reference/configuration/
  "$schema": "https://biomejs.dev/schemas/1.7.0/schema.json",
  // Enable auto-sorting of imports. When using Visual Studio Code, make sure
  // that your settings contain:
  // "editor.codeActionsOnSave": {
  //   "quickfix.biome": "explicit",
  //   "source.organizeImports.biome": "explicit"
  // },
  // See: https://biomejs.dev/reference/configuration/#organizeimports
  "organizeImports": {
    "enabled": true
  },
  "files": {
    "ignoreUnknown": true,
    // Ignore generated files.
    // See: https://biomejs.dev/reference/configuration/#filesignore
    "ignore": ["generated.ts", "**/generated/*", "**/dist/*", "bundle.js"]
  },
  "linter": {
    "enabled": true,
    "rules": {
      "a11y": {
        // We use SVG a lot across our apps, but we rarely want to add a `title`
        // attribute because we use SVG decoratively, and always add a label
        // when necessary.
        // See: https://biomejs.dev/linter/rules/no-svg-without-title/
        "noSvgWithoutTitle": "off",
        // We have our thing going for subtitles, so we do not want to enforce
        // the use of captions with every native video and audio players.
        // See: https://biomejs.dev/linter/rules/use-media-caption/
        "useMediaCaption": "off"
      },
      "complexity": {
        // Opposing `Array.prototype.forEach` in favor of for..of is a bit much
        // for a linting rule. There are cases where `forEach` are perfectly
        // legitimate.
        // See: https://biomejs.dev/linter/rules/no-for-each/
        "noForEach": "off"
      },
      "correctness": {
        // Undeclared variables are not reported as a problem by default, but
        // this is a behavior we want to enforce. Note that build flags need to
        // be listed as available globals in the `javascript.global` array.
        // See: https://biomejs.dev/linter/rules/no-undeclared-variables/
        "noUndeclaredVariables": "error",
        // Undeclared imports are not reported as a problem by default, but this
        // is a behavior we want to enforce.
        // See: https://biomejs.dev/linter/rules/no-undeclared-variables/
        "noUnusedImports": "error",
        // Unused variables are not reported as a problem by default, but this
        // is a behavior we want to enforce. We have a SCM to keep track of
        // unused code and should not resort to leaving it in the code base.
        // See: https://biomejs.dev/linter/rules/no-unused-variables/
        "noUnusedVariables": "error",
        // Normally, we’d want to ensure all hooks have an exhaustive list of
        // dependencies, but we have a lot of failing cases which would take a
        // while to adjust and double-check.
        // See: https://biomejs.dev/linter/rules/use-exhaustive-dependencies/
        "useExhaustiveDependencies": "warn",
        // This is the equivalent to the ESLint “rules-of-hooks” rule, which
        // enforces using hooks inside components only, outside of conditional
        // structures like `if` and ternary statements. It is not enabled by
        // default but we should pay attention because it can avoid runtime
        // errors.
        // See: https://biomejs.dev/linter/rules/use-hook-at-top-level/
        "useHookAtTopLevel": "error"
      },
      "performance": {
        // Using the spread operator on `Array.prototype.reduce` accumulators
        // is conceptually much slower than mutating the accumulator variable
        // because it creates new data with every pass on the array. That being
        // said, it’s not our performance bottleneck and we have a lot of cases
        // where we do that, so we turn it off.
        // See: https://biomejs.dev/linter/rules/no-accumulating-spread/
        "noAccumulatingSpread": "off"
      },
      "style": {
        // This rule prevents reassigned function parameters, but we do this a
        // lot, particularly in the backend API so although we want to limit it
        // as much as possible, we don’t want the rule to be an impediment.
        // See: https://biomejs.dev/linter/rules/no-parameter-assign/
        "noParameterAssign": "off",
        // Marking type imports as such helps with readability, compatibility
        // with bundlers and can avoid some weird performance edge cases.
        // See: https://biomejs.dev/linter/rules/use-import-type/
        "useImportType": "error"
      },
      "suspicious": {
        // Yes, using the array index as a React key is an anti-pattern, but in
        // many cases, it’s all we have as a differentiator, and it’s perfectly
        // fine when the array doesn’t get reordered.
        // See: https://biomejs.dev/linter/rules/no-array-index-key/
        "noArrayIndexKey": "warn",
        // Hooks shouldn’t need to be duplicated within `describe` blocks.
        // See: https://biomejs.dev/linter/rules/no-duplicate-test-hooks/
        "noDuplicateTestHooks": "error",
        // Prevents exporting things from test files.
        // See: https://biomejs.dev/linter/rules/no-exports-in-test/
        "noExportsInTest": "error",
        // Make sure we cannot commit a `describe` or `it` block with `.only`.
        // See: https://biomejs.dev/linter/rules/no-focused-tests/
        "noFocusedTests": "error",
        // The `yup` library uses `then` for some advanced schema definitions,
        // which is why we make this rule non-erroring.
        // See: https://biomejs.dev/linter/rules/no-then-property/
        "noThenProperty": "warn"
      }
    }
  },
  "formatter": {
    "enabled": true,
    "lineWidth": 120,
    "indentWidth": 2,
    "indentStyle": "space"
  },
  "javascript": {
    "formatter": {
      "arrowParentheses": "always",
      "jsxQuoteStyle": "double",
      "quoteStyle": "single",
      "semicolons": "always",
      "trailingComma": "es5"
    },
    "globals": [
      // The following globals are the build flags, which need to be maintained
      // here as well for the `noUndeclaredVariables` linting rule not to flag
      // them as missing.
      "__INTEGRATED_INTRO_OUTRO_EDITOR__",
      "__DISABLE_COMOTION_NG__",
      "__VIDEO_BRIEFING__",
      "__DIRECT_TEMPLATE_BUNDLE_IMPORTS__",
      // The following globals are test-related, covering both unit tests with
      // Jest and end-to-end tests with Cypress.
      "it",
      "describe",
      "expect",
      "jest",
      "before",
      "beforeAll",
      "beforeEach",
      "after",
      "afterAll",
      "afterEach",
      "Cypress",
      "cy"
    ]
  },
  "vcs": {
    "enabled": true,
    "clientKind": "git",
    "useIgnoreFile": true,
    "defaultBranch": "main"
  }
}