eslint.config.js

import noCrossDomainImports from "@gitbutler/no-cross-domain-imports";
import noRelativeImportPaths from "@gitbutler/no-relative-imports";
import js from "@eslint/js";
import { defineConfig } from "eslint/config";
import prettier from "eslint-config-prettier";
import { createNextImportResolver } from "eslint-import-resolver-next";
import pluginImportX from "eslint-plugin-import-x";
import svelte from "eslint-plugin-svelte";
import globals from "globals";
import ts from "typescript-eslint";

export default defineConfig(
	js.configs.recommended,
	...ts.configs.recommended,
	...svelte.configs.recommended,
	prettier,
	...svelte.configs.prettier,
	{
		languageOptions: {
			globals: {
				...globals.browser,
				...globals.node,
			},
			parserOptions: {
				projectService: {
					// This prevents lint error when running eslint from
					// subdirectories, ignoring the root tsconfig.json
					allowDefaultProject: [
						"svelte.config.js",
						"packages/ui/.storybook/*.ts",
						"packages/ui/playwright-ct.config.ts",
					],
				},
			},
		},
		rules: {
			"no-console": ["error", { allow: ["warn", "error"] }],
			"@typescript-eslint/no-namespace": "off",
			"@typescript-eslint/no-empty-function": "off",
			"@typescript-eslint/no-explicit-any": "off",
			"@typescript-eslint/no-unused-vars": [
				"error",
				{
					argsIgnorePattern: "^_",
					varsIgnorePattern: "^_",
					caughtErrorsIgnorePattern: "^_",
				},
			],
			"@typescript-eslint/return-await": ["error", "always"],
			"@typescript-eslint/promise-function-async": "error",
			"@typescript-eslint/await-thenable": "error",
			"@typescript-eslint/no-unnecessary-type-assertion": "error",

			eqeqeq: ["error", "always"],
			"import-x/no-cycle": "error",
			"import-x/order": [
				"error",
				{
					alphabetize: {
						order: "asc",
						orderImportKind: "asc",
						caseInsensitive: false,
					},
					groups: [
						"index",
						"sibling",
						"parent",
						"internal",
						"external",
						"builtin",
						"object",
						"type",
					],
					// Add explicit pathGroups to define what imports go in which groups
					pathGroups: [
						// Define monorepo paths as internal
						{ pattern: "apps/**", group: "internal" },
						{ pattern: "packages/**", group: "internal" },
						{ pattern: "e2e/**", group: "internal" },
						// Add SvelteKit paths
						{ pattern: "$lib/**", group: "internal" },
						{ pattern: "$components/**", group: "internal" },
						{ pattern: "$app/**", group: "internal" },
					],
					// Ensure certain import types are only categorized by their type
					pathGroupsExcludedImportTypes: ["builtin", "external", "object", "type"],
				},
			],
			"func-style": [2, "declaration"],
			"no-return-await": "off",
			"svelte/no-at-html-tags": "off",
			"svelte/button-has-type": [
				"error",
				{
					button: true,
					submit: true,
					reset: true,
				},
			],
			"no-relative-import-paths/no-relative-import-paths": "error",
			"no-cross-domain-imports/no-cross-domain-imports": ["error", { maxDomains: 2 }],
			"no-undef": "off", // eslint faq advises `no-undef` turned off for typescript projects.
			"svelte/require-each-key": "off",
			"svelte/no-inspect": "error",
			"svelte/no-at-debug-tags": "error",
			"svelte/no-unused-props": "error",
			"svelte/prefer-svelte-reactivity": "off",
			// eslint-plugin-svelte 3.15.0 added this to recommended and it is too noisy for current routing usage.
			"svelte/no-navigation-without-resolve": "off",
		},

		settings: {
			"import-x/extensions": [".ts", ".js", ".mjs"],
			"import-x/parsers": {
				"@typescript-eslint/parser": [".ts", ".js", ".mjs"],
			},
			"import-x/resolver-next": [createNextImportResolver()],
		},
		plugins: {
			"import-x": pluginImportX,
			"no-relative-import-paths": noRelativeImportPaths,
			"no-cross-domain-imports": noCrossDomainImports,
		},
	},
	{
		// Composition-layer folders and routes compose across domains by design — no restriction.
		files: ["apps/desktop/src/components/views/**", "apps/desktop/src/routes/**"],
		rules: {
			"no-cross-domain-imports/no-cross-domain-imports": "off",
		},
	},
	{
		files: ["**/*.svelte", "**/*.svelte.ts"],
		...ts.configs.disableTypeChecked,
	},
	{
		files: ["**/*.svelte", "**/*.svelte.ts"],
		languageOptions: {
			parserOptions: {
				parser: ts.parser,
			},
		},
	},
	{
		ignores: [
			"apps/lite/**",
			"**/.*", // dotfiles aren't ignored by default in FlatConfig
			".*", // dotfiles aren't ignored by default in FlatConfig
			"**/.DS_Store",
			"**/node_modules",
			"**/butler/target",
			"**/build",
			"**/static",
			"**/dist",
			"**/.svelte-kit",
			"**/package",
			"**/.env",
			"**/.env.*",
			"!**/.env.example",
			"**/pnpm-lock.yaml",
			"**/package-lock.json",
			"**/yarn.lock",
			".github",
			".vscode",
			"**/.pnpm-store",
			"**/vite.config.ts.timestamp-*",
			"!**/.storybook",
			"target/",
			"crates/",
			"apps/desktop/embedded-frontend",
			"packages/ui/storybook-static",
			// Storybook Meta type wrapper
			"packages/ui/src/stories/**/*.stories.ts",
			// but-sdk generated code
			"packages/but-sdk/src/generated",
			// Standalone scripts not covered by a tsconfig
			"scripts/**",
		],
	},
);