Add support autofix with checkAgainstRule

.changeset/tricky-wolves-collect.md

@@ -0,0 +1,5 @@
+---
+"stylelint": minor
+---
+
+Added: support autofix with `checkAgainstRule`

docs/developer-guide/plugins.md

@@ -240,6 +240,7 @@ It accepts an options object and a callback that is invoked with warnings from t
 - `ruleSettings`: settings for the rule you are invoking
 - `root`: the root node to run this rule against
 - `result?`: the PostCSS result for resolving and invoking custom rules
+- `context?`: the [context](rules.md#add-autofix) for the rule you are invoking
 
 Use the warning to create a _new_ warning _from your plugin rule_ that you report with `stylelint.utils.report`.
 
@@ -250,7 +251,7 @@ const allowableAtRules = [
   /* .. */
 ];
 
-function myPluginRule(primaryOption, secondaryOptionObject) {
+function myPluginRule(primaryOption, secondaryOptionObject, ruleContext) {
   return (postcssRoot, postcssResult) => {
     const defaultedOptions = Object.assign({}, secondaryOptionObject, {
       ignoreAtRules: allowableAtRules.concat(options.ignoreAtRules || [])
@@ -261,7 +262,8 @@ function myPluginRule(primaryOption, secondaryOptionObject) {
         ruleName: "at-rule-no-unknown",
         ruleSettings: [primaryOption, defaultedOptions],
         root: postcssRoot,
-        result: postcssResult
+        result: postcssResult,
+        context: ruleContext
       },
       (warning) => {
         stylelint.utils.report({

lib/utils/__tests__/checkAgainstRule.test.js

@@ -87,6 +87,26 @@ describe('checkAgainstRule', () => {
 		expect(warnings[0].column).toBe(1);
 	});
 
+	it('outputs fixed code when provided a context object', () => {
+		const root = postcss.parse('  a { color: red; }');
+		const context = { fix: true };
+
+		const warnings = [];
+
+		checkAgainstRule(
+			{
+				ruleName: 'indentation',
+				ruleSettings: 2,
+				root,
+				context,
+			},
+			(warning) => warnings.push(warning),
+		);
+
+		expect(warnings).toHaveLength(0);
+		expect(root.toString()).toBe('a { color: red; }');
+	});
+
 	it('checks against custom rule (passing)', () => {
 		const root = postcss.parse('.not-empty {}');
 

lib/utils/checkAgainstRule.js

@@ -16,7 +16,7 @@ function checkAgainstRule(options, callback) {
 
 	if (!callback) throw new Error('Expected a callback function');
 
-	const { ruleName, ruleSettings, root, result } = options;
+	const { ruleName, ruleSettings, root, result, context = {} } = options;
 
 	if (!ruleName) throw new Error('Expected a "ruleName" option');
 
@@ -37,7 +37,7 @@ function checkAgainstRule(options, callback) {
 	// @ts-expect-error - this error should not occur with PostCSS 8
 	const tmpPostcssResult = new Result();
 
-	rule(settings[0], /** @type {Object} */ (settings[1]), {})(root, tmpPostcssResult);
+	rule(settings[0], /** @type {Object} */ (settings[1]), context)(root, tmpPostcssResult);
 
 	for (const warning of tmpPostcssResult.warnings()) callback(warning);
 }

types/stylelint/index.d.ts

@@ -148,11 +148,6 @@ declare module 'stylelint' {
 
 		export type CustomSyntax = string | PostCSS.Syntax;
 
-		export type PluginContext = {
-			fix?: boolean | undefined;
-			newline?: string | undefined;
-		};
-
 		// Note: With strict function types enabled, function signatures are checked contravariantly.
 		// This means that it would not be possible for rule authors to narrow the message function
 		// parameters to e.g. just `string`. Declaring the type for rule message functions through
@@ -180,10 +175,20 @@ declare module 'stylelint' {
 			optional?: boolean;
 		};
 
+		export type RuleContext = {
+			fix?: boolean | undefined;
+			newline?: string | undefined;
+		};
+
+		/**
+		 * @deprecated Use `RuleContext` instead.
+		 */
+		export type PluginContext = RuleContext;
+
 		export type RuleBase<P = any, S = any> = (
 			primaryOption: P,
 			secondaryOptions: Record<string, S>,
-			context: PluginContext,
+			context: RuleContext,
 		) => (root: PostCSS.Root, result: PostcssResult) => Promise<void> | void;
 
 		export type RuleMeta = {
@@ -518,6 +523,7 @@ declare module 'stylelint' {
 						ruleSettings: ConfigRuleSettings<T, O>;
 						root: PostCSS.Root;
 						result?: PostcssResult;
+						context?: RuleContext;
 					},
 					callback: (warning: PostCSS.Warning) => void,
 				) => void;