.eslintrc

{
  "$schema": "https://json.schemastore.org/eslintrc.json",
  "plugins": ["@typescript-eslint", "require-form-method", "node", "vitest"],
  "parserOptions": {
    "project": "tsconfig.json"
  },
  "extends": [
    "next",
    "next/core-web-vitals",
    "plugin:@typescript-eslint/recommended",
    "plugin:@typescript-eslint/recommended-requiring-type-checking",
    "plugin:import/recommended",
    "plugin:import/typescript",
    "prettier",
    "plugin:vitest/recommended",
    "plugin:@saleor/saleor-app/recommended"
  ],
  "rules": {
    // use double quotes, allow template strings
    "quotes": ["error", "double", { "avoidEscape": true }],

    // sort imports
    "import/order": "error",

    // no let exports
    "import/no-mutable-exports": "error",

    "import/no-cycle": "error",
    "import/no-default-export": "error",

    // prevent default import from Sentry because it doesn't work 😬
    "no-restricted-syntax": [
      "error",
      {
        "selector": "ImportDeclaration[source.value='@sentry/nextjs'] > ImportDefaultSpecifier",
        "message": "Use `import * as Sentry from '@sentry/nextjs';`"
      }
    ],

    // allow {} even though it's unsafe but comes handy
    "@typescript-eslint/ban-types": [
      "error",
      {
        "types": {
          "{}": false
        }
      }
    ],

    "@typescript-eslint/consistent-type-imports": [
      "error",
      {
        "prefer": "type-imports",
        "fixStyle": "inline-type-imports",
        "disallowTypeAnnotations": false
      }
    ],

    "import/no-duplicates": ["error", { "prefer-inline": true }],

    "@typescript-eslint/no-restricted-imports": [
      "error",
      {
        "patterns": [
          {
            "group": ["@/__tests__/test-env.mjs"],
            "message": "Test envs cannot be imported into application code"
          }
        ]
      }
    ],

    "node/no-process-env": ["error"],

    // false negatives
    "import/namespace": ["off"],

    // we allow empty interfaces
    "no-empty-pattern": "off",
    "@typescript-eslint/no-empty-interface": "off",

    // we allow empty functions
    "@typescript-eslint/no-empty-function": "off",

    // we sometimes use async functions that don't await anything
    "@typescript-eslint/require-await": "off",

    // make sure to `await` inside try…catch
    "@typescript-eslint/return-await": ["error", "in-try-catch"],

    // allow unused vars prefixed with `_`
    "@typescript-eslint/no-unused-vars": [
      "error",
      { "argsIgnorePattern": "^_", "varsIgnorePattern": "^_" }
    ],

    // numbers and booleans are fine in template strings
    "@typescript-eslint/restrict-template-expressions": [
      "error",
      { "allowNumber": true, "allowBoolean": true }
    ],

    // for security reasons, always require forms to provide method="post"
    "require-form-method/require-form-method": "error",

    // for security reasons, always require buttons to provide type="button" ("submit" on rare occasions)
    "react/button-has-type": ["error", { "button": true, "submit": true, "reset": false }]
  },
  "overrides": [
    {
      "files": ["*.test.tsx", "*.test.ts", "**/__tests__/**/*.ts?(x)"],
      "rules": {
        // let's make our lives easier in tests
        "@typescript-eslint/no-unsafe-assignment": "off",
        "@typescript-eslint/no-unsafe-member-access": "off",
        "@typescript-eslint/no-unsafe-return": "off",
        "@typescript-eslint/no-explicit-any": "off",
        "@typescript-eslint/no-non-null-assertion": "off",

        // allow imports from testEnv
        "@typescript-eslint/no-restricted-imports": "off"
      }
    },
    {
      // https://github.com/testing-library/eslint-plugin-testing-library#run-the-plugin-only-against-test-files
      "files": ["**/__tests__/**/*.[jt]sx", "**/?(*.)+(spec|test).[jt]sx"],
      "extends": ["plugin:testing-library/react"]
    },
    {
      // We allow process.env access in env.mjs and testEnv.mjs
      "files": ["**/env.mjs", "**/test-env.mjs", "next.config.mjs"],
      "rules": {
        "node/no-process-env": "off"
      }
    },
    {
      "files": ["src/pages/**/*.ts?(x)"],
      "rules": {
        "import/no-default-export": "off"
      }
    },
    {
      "files": ["*.cjs", "*.cts"],
      "rules": {
        "@typescript-eslint/no-var-requires": "off"
      }
    }
  ],
  "ignorePatterns": ["*.js", "*.jsx"]
}