Fix up stylelint plugin

Author: webpro

packages/knip/fixtures/plugins/stylelint3/package.json

@@ -0,0 +1,9 @@
+{
+  "name": "@fixtures/stylelint3",
+  "devDependencies": {
+    "stylelint": "*",
+    "stylelint-config-recommended": "*",
+    "stylelint-plugin-logical-css": "*",
+    "postcss-styled-syntax": "*"
+  }
+}

packages/knip/fixtures/plugins/stylelint3/stylelint.config.mjs

@@ -0,0 +1,11 @@
+/** @type {import('stylelint').Config} */
+export default {
+  extends: [
+    {
+      extends: ['stylelint-config-recommended'],
+      customSyntax: 'postcss-styled-syntax',
+      plugins: ['stylelint-plugin-logical-css'],
+      rules: {},
+    },
+  ],
+};

packages/knip/src/plugins/stylelint/index.ts

@@ -2,7 +2,7 @@ import type { IsPluginEnabled, Plugin, ResolveConfig } from '../../types/config.
 import { type Input, toDeferResolve } from '../../util/input.js';
 import { toCosmiconfig } from '../../util/plugin-config.js';
 import { hasDependency } from '../../util/plugin.js';
-import type { BaseStyleLintConfig, StyleLintConfig } from './types.js';
+import type { StyleLintConfig } from './types.js';
 
 // https://stylelint.io/user-guide/configure/
 
@@ -14,17 +14,21 @@ const isEnabled: IsPluginEnabled = ({ dependencies }) => hasDependency(dependenc
 
 const config = ['package.json', ...toCosmiconfig('stylelint')];
 
-const resolve = (config: StyleLintConfig | BaseStyleLintConfig): Input[] => {
-  const extend = config.extends ?? [];
-  const plugins = config.plugins?.flatMap(plugin => (typeof plugin === 'string' ? [plugin] : [])) ?? [];
-  const customSyntax: string[] = typeof config.customSyntax === 'string' ? [config.customSyntax] : [];
-
-  const overrideConfigs = 'overrides' in config ? config.overrides.flatMap(resolve) : [];
-  return [...[extend, plugins, customSyntax].flat().map(toDeferResolve), ...overrideConfigs];
+const resolveConfig: ResolveConfig<StyleLintConfig> = async (config, options) => {
+  const inputs: Input[] = [];
+  const extend = Array.isArray(config.extends) ? config.extends : config.extends ? [config.extends] : [];
+  for (const id of extend) {
+    if (typeof id === 'string') inputs.push(toDeferResolve(id));
+    else for (const x of await resolveConfig(id, options)) inputs.push(x);
+  }
+  for (const plugin of config.plugins ?? []) if (typeof plugin === 'string') inputs.push(toDeferResolve(plugin));
+  if (typeof config.customSyntax === 'string') inputs.push(toDeferResolve(config.customSyntax));
+  for (const override of config.overrides ?? []) {
+    for (const input of await resolveConfig(override, options)) inputs.push(input);
+  }
+  return inputs;
 };
 
-const resolveConfig: ResolveConfig<StyleLintConfig> = config => resolve(config);
-
 export default {
   title,
   enablers,

packages/knip/src/plugins/stylelint/types.ts

@@ -1,9 +1,9 @@
-export type BaseStyleLintConfig = {
-  customSyntax?: unknown;
+interface BaseStyleLintConfig {
+  customSyntax?: string;
   extends?: string | string[];
-  plugins?: unknown[];
-};
+  plugins?: (string | BaseStyleLintConfig)[];
+}
 
-export type StyleLintConfig = BaseStyleLintConfig & {
-  overrides: BaseStyleLintConfig[];
-};
+export interface StyleLintConfig extends BaseStyleLintConfig {
+  overrides?: BaseStyleLintConfig[];
+}

packages/knip/test/plugins/stylelint3.test.ts

@@ -0,0 +1,21 @@
+import { test } from 'bun:test';
+import assert from 'node:assert/strict';
+import { main } from '../../src/index.js';
+import { resolve } from '../../src/util/path.js';
+import baseArguments from '../helpers/baseArguments.js';
+import baseCounters from '../helpers/baseCounters.js';
+
+const cwd = resolve('fixtures/plugins/stylelint3');
+
+test('Find dependencies with the stylelint plugin (3)', async () => {
+  const { counters } = await main({
+    ...baseArguments,
+    cwd,
+  });
+
+  assert.deepEqual(counters, {
+    ...baseCounters,
+    processed: 1,
+    total: 1,
+  });
+});