Fix Could not find a declaration file for module 'css-tree' type error (#8452)

Co-authored-by: Richard Hallows <jeddy3@users.noreply.github.com>

Author: danielrentz

.changeset/plenty-starfishes-invent.md

@@ -0,0 +1,5 @@
+---
+"stylelint": minor
+---
+
+Fixed: `Could not find a declaration file for module 'css-tree'` type error

docs/developer-guide/rules.md

@@ -307,7 +307,6 @@ function rule(primary, secondary) {
 - `configurationComment`(string): String that prefixes configuration comments like `/* stylelint-disable */`.
 - `fix`(boolean): If `true`, your rule can apply autofixes.
 - `newline`(string): Line-ending used in current linted file.
-- `lexer`(object): The [CSSTree](https://github.com/csstree/csstree) lexer, which helps in parsing and validating CSS syntax dynamically. The lexer is initialized once per lint session and reused across rules.
 
 > [!WARNING]
 > The convention of restricting the appliance of fixes based on the `context.fix` property is deprecated in favour of recommending the `fix` callback which properly handles [configuration comments](../user-guide/ignore-code.md#parts-of-a-file).

lib/utils/getLexer.cjs

@@ -1,11 +1,15 @@
+/**
+ * @typedef {import('css-tree').Lexer} Lexer
+ */
+
 /**
  * @param {import('stylelint').RuleContext} context
- * @returns {import('css-tree').Lexer}
+ * @returns {Lexer}
  */
 export default function getLexer(context) {
 	if (!context?.lexer) {
 		throw new Error('Expected a "lexer" object');
 	}
 
-	return context.lexer;
+	return /** @type Lexer */ (context.lexer);
 }

lib/utils/getLexer.mjs

@@ -1,7 +1,6 @@
 import type * as PostCSS from 'postcss';
 import type { GlobbyOptions } from 'globby';
 import type { cosmiconfig, TransformSync as CosmiconfigTransformSync } from 'cosmiconfig';
-import type { Lexer } from 'css-tree';
 
 type ConfigExtends = string | string[];
 
@@ -371,7 +370,8 @@ declare namespace stylelint {
 		configurationComment?: string | undefined;
 		fix?: boolean | undefined;
 		newline?: string | undefined;
-		lexer?: Lexer | undefined;
+		/** @internal */
+		lexer?: unknown | undefined;
 	};
 
 	/** @internal */