biome.jsonc

{
  "$schema": "https://biomejs.dev/schemas/2.4.16/schema.json",
  // House lint stack (D22): Ultracite presets over Biome, triple-pinned —
  // this file, the lefthook pre-commit command, and the devDeps all name
  // @biomejs/biome 2.4.16 + ultracite 7.8.2. Config over comments: when a rule
  // fights how this codebase actually works, turn it off HERE with a reason.
  "extends": [
    "ultracite/biome/core",
    "ultracite/biome/next",
    "ultracite/biome/react"
  ],
  "vcs": {
    "enabled": true,
    "clientKind": "git",
    "useIgnoreFile": true
  },
  "files": {
    "includes": [
      "!packages/lingo/bench/*.json",
      // Generated copies of bench data (scripts/sync-site.mjs) — same as the
      // bench source exclusion above.
      "!apps/site/src/data/*.json",
      "!packages/lingo/tests/corpus",
      "!packages/lingo/demo",
      "!apps/site/public",
      // shadcn-managed primitives (house rule, same as the sibling repos):
      "!apps/site/src/components/ui",
      "!**/.next*",
      "!**/dist",
      "!bun.lock"
    ]
  },
  "formatter": {
    "indentStyle": "space",
    "indentWidth": 2,
    "lineWidth": 100
  },
  "javascript": {
    "formatter": {
      "quoteStyle": "single",
      "jsxQuoteStyle": "double",
      "semicolons": "asNeeded",
      "trailingCommas": "all"
    }
  },
  "linter": {
    "rules": {
      "style": {
        // Strict TS + noUncheckedIndexedAccess makes `!` after a guard
        // idiomatic (hot paths in suggest.ts, registry.ts).
        "noNonNullAssertion": "off",
        // Recursive-descent grammar reads as condition chains; nested
        // ternaries are the established house style here.
        "noNestedTernary": "off",
        // `arr[arr.length - 1]` stays: .at() adds a call on D17-measured hot
        // paths for no semantic gain.
        "useAtIndex": "off",
        // Fable- and Codex-authored modules mix T[] / Array<T> and
        // interface / type by local readability; not worth a churn pass.
        "useConsistentArrayType": "off",
        "useConsistentTypeDefinitions": "off",
        "useShorthandAssign": "off",
        // Exhaustive switches over closed unions: TS checks them; a default
        // clause would be dead code.
        "useDefaultSwitchClause": "off",
        // Indexed loops with position math (registry matchKey) are the hot
        // path; for-of over strings allocates an iterator.
        "useForOf": "off",
        // Parser state threading mutates parameters deliberately.
        "noParameterAssign": "off",
        // Quantity/QuantityRange fields: readonly-ification is a public-API
        // semantics question, not a lint fix — revisit deliberately.
        "useReadonlyClassProperties": "off",
        // Subpath entries (./core, ./date, …) ARE barrels — that's the
        // packaging design (plan 001); grammar.ts is a load-bearing facade
        // (imports never moved — see wiki/conventions.md).
        "noExportedImports": "off",
        // The lingoInput namespace merge carries the .get() static; DOM
        // controller constructor properties are deliberate.
        "noNamespace": "off",
        "noParameterProperties": "off",
        // Sole violation is a two-default test helper; reordering its params
        // would churn call sites for zero clarity gain.
        "useDefaultParameterLast": "off"
      },
      "performance": {
        // A text parser runs regexes inside functions by design; perf is
        // gated by the bench suite (D17/D19), not by regex placement.
        "useTopLevelRegex": "off",
        "noBarrelFile": "off",
        // `import * as React` is the required shape for the react entry.
        "noNamespaceImport": "off",
        // Single use (errors.ts): builds issue.data minus suggestions on a
        // fresh copy; the undefined-assign autofix would change
        // Object.keys() semantics and attach empty data objects.
        "noDelete": "off"
      },
      "complexity": {
        // Hand-rolled recursive descent (D3): grammar functions are long and
        // branchy on purpose; splitting them hides the grammar.
        "noExcessiveCognitiveComplexity": "off",
        "useLiteralKeys": "off",
        "noVoid": "off",
        "noForEach": "off"
      },
      "suspicious": {
        // D17 char-mask prescreen and friends are bitwise by design.
        "noBitwiseOperators": "off",
        // Async-contract functions without awaits are deliberate: Next server
        // actions, Standard Schema validate (async by interface), eval CLI.
        "useAwait": "off",
        // `while ((m = scan()))` is the scanner idiom in registry/tests.
        "noAssignInExpressions": "off",
        // Empty catch = feature probe (bench harness, clipboard demo).
        "noEmptyBlockStatements": "off"
      },
      "correctness": {
        // tsc (strict) owns undeclared/ambient-type resolution; biome
        // false-positives on TS ambient types.
        "noUndeclaredVariables": "off",
        // Hook deps are owned by eslint react-hooks (RC sweep green) and
        // react-doctor triage — deliberate subscribe-only effects exist.
        "useExhaustiveDependencies": "off",
        // Public signatures keep reserved params (formatCompound's opts is
        // documented API surface); internal cases reviewed 2026-07-04.
        "noUnusedFunctionParameters": "off"
      }
    }
  },
  "overrides": [
    {
      "includes": ["apps/site/**"],
      "linter": {
        "rules": {
          "security": {
            // Site-only: shiki-rendered code HTML and JSON-LD structured
            // data are the two sanctioned dangerouslySetInnerHTML uses.
            "noDangerouslySetInnerHtml": "off"
          },
          "a11y": {
            // Base UI render-prop anchors (<a aria-label .../> as Button
            // render) receive slotted children at runtime — biome sees an
            // empty anchor; the DOM isn't one. WCAG-audited 2026-07-04.
            "useAnchorContent": "off",
            // Logo decides decorative-vs-named at runtime (aria-hidden or
            // accessible name from props) — static analysis can't see it.
            "noSvgWithoutTitle": "off",
            // role="group" on styled flex containers stays: fieldset's UA
            // styling (min-inline-size, borders) breaks the layouts.
            "useSemanticElements": "off",
            // Escape/arrow-key handling on the role="dialog" container is
            // the APG modal pattern.
            "noNoninteractiveElementInteractions": "off",
            // role="list" on <ul> is kept deliberately: Safari/VoiceOver drop
            // list semantics when list-style is removed (Tailwind preflight).
            "noRedundantRoles": "off"
          },
          "suspicious": {
            // Static split-text (per-char/word spans) and positional JSON
            // rows never reorder — index keys are correct there.
            "noArrayIndexKey": "off",
            // Callback unions keep `| void`: side-effect-only handlers must
            // stay assignable (undefined would reject inferred-void fns).
            "noConfusingVoidType": "off"
          }
        }
      }
    }
  ]
}