Cybersecurity-Projects/TEMPLATES/biome.json.example

{
  "//": [
    "©AngelaMos | 2026",
    "biome.json.example",
    "",
    "Annotated Biome configuration for Cybersecurity-Projects frontends.",
    "Copy into your frontend/ directory, rename to biome.json.",
    "",
    "Biome is an all-in-one linter + formatter for JS/TS/JSON/CSS.",
    "It replaces ESLint + Prettier in a single Rust-based binary.",
    "",
    "Docs:  https://biomejs.dev/reference/configuration/",
    "Rules: https://biomejs.dev/linter/rules/"
  ],

  "$schema": "https://biomejs.dev/schemas/2.4.2/schema.json",

  "// vcs": "Integrates with Git so Biome respects your .gitignore automatically.",
  "vcs": {
    "enabled": true,
    "clientKind": "git",
    "useIgnoreFile": true
  },

  "// files": "Only process source files. Biome auto-skips lock files and node_modules.",
  "files": {
    "includes": ["**/*.ts", "**/*.tsx", "**/*.js", "**/*.jsx", "**/*.json"]
  },

  "// formatter": [
    "Global formatting rules. These apply to all languages.",
    "indentWidth 2 and lineWidth 82 match the repo standard.",
    "lineEnding 'lf' enforces Unix-style line endings everywhere."
  ],
  "formatter": {
    "enabled": true,
    "indentStyle": "space",
    "indentWidth": 2,
    "lineWidth": 82,
    "lineEnding": "lf"
  },

  "// javascript": [
    "JS/TS-specific formatter settings.",
    "quoteStyle 'single' for JS, 'double' for JSX (React convention).",
    "semicolons 'asNeeded' = no semis except where ASI would be ambiguous.",
    "trailingCommas 'es5' = trailing commas in arrays/objects but not function params."
  ],
  "javascript": {
    "formatter": {
      "quoteStyle": "single",
      "jsxQuoteStyle": "double",
      "semicolons": "asNeeded",
      "trailingCommas": "es5",
      "arrowParentheses": "always"
    }
  },

  "// linter": [
    "Start with 'recommended' (curated safe defaults), then tune per-domain.",
    "Do NOT use 'all' — it enables 300+ conflicting rules."
  ],
  "linter": {
    "enabled": true,
    "rules": {
      "recommended": true,

      "// complexity": "Keeps code readable. noForEach off because .forEach is fine for side effects.",
      "complexity": {
        "noExcessiveCognitiveComplexity": {
          "level": "error",
          "options": { "maxAllowedComplexity": 25 }
        },
        "noForEach": "off",
        "useLiteralKeys": "off"
      },

      "// correctness": "Catches real bugs. These should almost always be errors.",
      "correctness": {
        "noUnusedVariables": "error",
        "noUnusedImports": "error",
        "useExhaustiveDependencies": "warn",
        "useHookAtTopLevel": "error",
        "noUndeclaredVariables": "error"
      },

      "// style": [
        "Enforces consistent patterns across the codebase.",
        "useImportType separates type imports (tree-shaking friendly).",
        "noNonNullAssertion bans `!` postfix (override in main.tsx via overrides).",
        "useNamingConvention is off — too noisy with API response shapes."
      ],
      "style": {
        "useImportType": "error",
        "useConst": "error",
        "useTemplate": "error",
        "useSelfClosingElements": "error",
        "useFragmentSyntax": "error",
        "noNonNullAssertion": "error",
        "useConsistentArrayType": {
          "level": "error",
          "options": { "syntax": "shorthand" }
        },
        "useNamingConvention": "off"
      },

      "// suspicious": [
        "Catches code that is almost certainly a mistake.",
        "noExplicitAny = error forces proper typing (the whole point of TS).",
        "noConsole = warn because console.log is fine in dev but should be flagged."
      ],
      "suspicious": {
        "noExplicitAny": "error",
        "noDebugger": "error",
        "noConsole": "warn",
        "noArrayIndexKey": "warn",
        "noAssignInExpressions": "error",
        "noDoubleEquals": "error",
        "noRedeclare": "error",
        "noVar": "error"
      },

      "// security": "Prevents XSS vectors in React components.",
      "security": {
        "noDangerouslySetInnerHtml": "error"
      },

      "// a11y": "Accessibility rules. Non-negotiable for production UIs.",
      "a11y": {
        "useAltText": "error",
        "useAnchorContent": "error",
        "useKeyWithClickEvents": "error",
        "noStaticElementInteractions": "error",
        "useButtonType": "error",
        "useValidAnchor": "error"
      }
    }
  },

  "// overrides": [
    "Per-file rule overrides.",
    "main.tsx needs `document.getElementById('root')!` — the non-null assertion",
    "is safe here because the HTML template guarantees the element exists."
  ],
  "overrides": [
    {
      "includes": ["src/main.tsx"],
      "linter": {
        "rules": {
          "style": {
            "noNonNullAssertion": "off"
          }
        }
      }
    }
  ]
}