feat: support overrides in buildFromOxlintConfig(File)

src/build-from-oxlint-config/index.ts

@@ -1,7 +1,7 @@
 import fs from 'node:fs';
-import type { Linter } from 'eslint';
 import JSONCParser from 'jsonc-parser';
-import {
+import type {
+  EslintPluginOxLintConfig,
   OxlintConfig,
   OxlintConfigCategories,
   OxlintConfigPlugins,
@@ -13,6 +13,7 @@ import {
   readCategoriesFromConfig,
 } from './categories.js';
 import { readPluginsFromConfig } from './plugins.js';
+import { handleOverridesScope, readOverridesFromConfig } from './overrides.js';
 
 // default plugins, see <https://oxc.rs/docs/guide/usage/linter/config#plugins>
 const defaultPlugins: OxlintConfigPlugins = ['react', 'unicorn', 'typescript'];
@@ -59,9 +60,10 @@ const getConfigContent = (
  */
 export const buildFromOxlintConfig = (
   config: OxlintConfig
-): Linter.Config<Record<string, 'off'>>[] => {
+): EslintPluginOxLintConfig[] => {
   const rules: Record<string, 'off'> = {};
   const plugins = readPluginsFromConfig(config) ?? defaultPlugins;
+  const categories = readCategoriesFromConfig(config) ?? defaultCategories;
 
   // it is not a plugin but it is activated by default
   plugins.push('eslint');
@@ -81,15 +83,22 @@ export const buildFromOxlintConfig = (
   const configRules = readRulesFromConfig(config);
 
   if (configRules !== undefined) {
-    handleRulesScope(configRules, rules);
+    handleRulesScope(configRules, rules, true);
   }
 
-  return [
+  const overrides = readOverridesFromConfig(config);
+  const configs: EslintPluginOxLintConfig[] = [
     {
       name: 'oxlint/from-oxlint-config',
       rules,
     },
   ];
+
+  if (overrides !== undefined) {
+    handleOverridesScope(overrides, configs, categories);
+  }
+
+  return configs;
 };
 
 /**
@@ -101,7 +110,7 @@ export const buildFromOxlintConfig = (
  */
 export const buildFromOxlintConfigFile = (
   oxlintConfigFile: string
-): Linter.Config<Record<string, 'off'>>[] => {
+): EslintPluginOxLintConfig[] => {
   const config = getConfigContent(oxlintConfigFile);
 
   // we could not parse form the file, do not build with default values

src/build-from-oxlint-config/overrides.ts

@@ -0,0 +1,48 @@
+import { handleCategoriesScope } from './categories.js';
+import { readPluginsFromConfig } from './plugins.js';
+import { handleRulesScope, readRulesFromConfig } from './rules.js';
+import {
+  EslintPluginOxLintConfig,
+  OxlintConfig,
+  OxlintConfigCategories,
+  OxlintConfigOverride,
+} from './types.js';
+
+export const handleOverridesScope = (
+  overrides: OxlintConfigOverride[],
+  configs: EslintPluginOxLintConfig[],
+  baseCategories?: OxlintConfigCategories
+): void => {
+  for (const overrideIndex in overrides) {
+    const override = overrides[overrideIndex];
+    const eslintRules: Record<string, 'off'> = {};
+    const eslintConfig: EslintPluginOxLintConfig = {
+      name: `oxlint/from-oxlint-config-override-${overrideIndex}`,
+    };
+
+    // expect that oxlint `files` syntax is the same as eslint
+    eslintConfig.files = override.files;
+
+    const plugins = readPluginsFromConfig(override);
+    if (baseCategories !== undefined && plugins !== undefined) {
+      handleCategoriesScope(plugins, baseCategories, eslintRules);
+    }
+
+    const rules = readRulesFromConfig(override);
+    if (rules !== undefined) {
+      // ToDo -- when off, we should enable the default settings
+      handleRulesScope(rules, eslintRules, false);
+    }
+
+    eslintConfig.rules = eslintRules;
+    configs.push(eslintConfig);
+  }
+};
+
+export const readOverridesFromConfig = (
+  config: OxlintConfig
+): OxlintConfigOverride[] | undefined => {
+  return 'overrides' in config && Array.isArray(config.overrides)
+    ? (config.overrides as OxlintConfigOverride[])
+    : undefined;
+};

src/build-from-oxlint-config/plugins.ts

@@ -1,11 +1,15 @@
-import { OxlintConfig, OxlintConfigPlugins } from './types.js';
+import {
+  OxlintConfig,
+  OxlintConfigOverride,
+  OxlintConfigPlugins,
+} from './types.js';
 
 /**
  * tries to return the "plugins" section from the config.
  * it returns `undefined` when not found or invalid.
  */
 export const readPluginsFromConfig = (
-  config: OxlintConfig
+  config: OxlintConfig | OxlintConfigOverride
 ): OxlintConfigPlugins | undefined => {
   return 'plugins' in config && Array.isArray(config.plugins)
     ? (config.plugins as OxlintConfigPlugins)

src/build-from-oxlint-config/rules.ts

@@ -2,7 +2,11 @@ import {
   aliasPluginNames,
   reactHookRulesInsideReactScope,
 } from '../constants.js';
-import { OxlintConfig, OxlintConfigRules } from './types.js';
+import {
+  OxlintConfig,
+  OxlintConfigOverride,
+  OxlintConfigRules,
+} from './types.js';
 import configByCategory from '../generated/configs-by-category.js';
 import { isObject } from './utils.js';
 
@@ -73,7 +77,8 @@ const isActiveValue = (value: unknown) =>
  */
 export const handleRulesScope = (
   oxlintRules: OxlintConfigRules,
-  rules: Record<string, 'off'>
+  rules: Record<string, 'off' | 'warn'>,
+  disableRule: boolean
 ): void => {
   for (const rule in oxlintRules) {
     const eslintName = getEsLintRuleName(rule);
@@ -90,7 +95,13 @@ export const handleRulesScope = (
       rules[eslintName] = 'off';
     } else if (rule in rules && isDeactivateValue(oxlintRules[rule])) {
       // rules extended by categories or plugins can be disabled manually
-      delete rules[eslintName];
+      if (disableRule) {
+        delete rules[eslintName];
+      }
+      // inside overrides we need to enable the rule again
+      else {
+        rules[eslintName] = 'warn';
+      }
     }
   }
 };
@@ -100,7 +111,7 @@ export const handleRulesScope = (
  * it returns `undefined` when not found or invalid.
  */
 export const readRulesFromConfig = (
-  config: OxlintConfig
+  config: OxlintConfig | OxlintConfigOverride
 ): OxlintConfigRules | undefined => {
   return 'rules' in config && isObject(config.rules)
     ? (config.rules as OxlintConfigRules)

src/build-from-oxlint-config/types.d.ts

@@ -1,9 +1,21 @@
+import type { Linter } from 'eslint';
+
 export type OxlintConfigPlugins = string[];
 
 export type OxlintConfigCategories = Record<string, unknown>;
 
 export type OxlintConfigRules = Record<string, unknown>;
 
+export type OxlintConfigOverride = {
+  files: string[];
+  plugins?: OxlintConfigPlugins;
+  rules?: OxlintConfigRules;
+};
+
+export type EslintPluginOxLintConfig = Linter.Config<
+  Record<string, 'off' | 'warn'>
+>;
+
 export type OxlintConfig = {
   [key: string]: unknown;
   plugins?: OxlintConfigPlugins;