feat: analyze @scope

src/atrules/atrules.test.ts

@@ -967,6 +967,58 @@ test('analyzes @property', () => {
 	expect(actual).toEqual(expected)
 })
 
+test('analyzes @scope', () => {
+	// Examples from
+	// https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules/@scope#examples
+	// and
+	// https://drafts.csswg.org/css-cascade-6/#scoped-styles
+	const fixture = `
+		@scope (.article-body) to (figure) {}
+
+		@scope (.article-body) {}
+
+		@scope (.article-body) to (:scope > figure) {}
+
+		@scope (.article-body) to (.feature :scope figure) {}
+
+		@scope (.media-object) to (.content > *) {}
+
+		@scope ([data-scope='main-component']) to ([data-scope]) {}
+
+		@scope ([data-scope='main-component']) to ([data-scope] > *) {}
+
+		@scope (.parent-scope) {
+			@scope (:scope > .child-scope) to (:scope .limit) {}
+		}
+
+		@scope (.parent-scope > .child-scope) to (.parent-scope > .child-scope .limit) {}
+
+    /* No prelude */
+    @scope {}
+  `
+	const result = analyze(fixture)
+	const actual = result.atrules.scope
+	const expected = {
+		total: 10,
+		totalUnique: 10,
+		unique: {
+			'(.article-body) to (figure)': 1,
+			'(.article-body)': 1,
+			'(.article-body) to (:scope > figure)': 1,
+			'(.article-body) to (.feature :scope figure)': 1,
+			'(.media-object) to (.content > *)': 1,
+			"([data-scope='main-component']) to ([data-scope])": 1,
+			"([data-scope='main-component']) to ([data-scope] > *)": 1,
+			'(.parent-scope)': 1,
+			'(:scope > .child-scope) to (:scope .limit)': 1,
+			'(.parent-scope > .child-scope) to (.parent-scope > .child-scope .limit)': 1,
+		},
+		uniquenessRatio: 1,
+	}
+
+	expect(actual).toEqual(expected)
+})
+
 test('tracks nesting depth', () => {
 	const fixture = `
     a {

src/index.test.ts

@@ -244,6 +244,12 @@ test('handles empty input gracefully', () => {
 				unique: {},
 				uniquenessRatio: 0,
 			},
+			scope: {
+				total: 0,
+				totalUnique: 0,
+				unique: {},
+				uniquenessRatio: 0,
+			},
 			complexity: {
 				min: 0,
 				max: 0,

src/index.ts

@@ -112,6 +112,7 @@ function analyzeInternal<T extends boolean>(css: string, options: Options, useLo
 	let containers = new Collection(useLocations)
 	let containerNames = new Collection(useLocations)
 	let registeredProperties = new Collection(useLocations)
+	let scopes = new Collection(useLocations)
 	let atruleNesting = new AggregateCollection()
 	let uniqueAtruleNesting = new Collection(useLocations)
 
@@ -294,6 +295,8 @@ function analyzeInternal<T extends boolean>(css: string, options: Options, useLo
 					registeredProperties.p(node.prelude.text, toLoc(node))
 				} else if (normalized_name === 'charset') {
 					charsets.p(node.prelude.text.toLowerCase(), toLoc(node))
+				} else if (normalized_name === 'scope') {
+					scopes.p(node.prelude.text, toLoc(node))
 				}
 
 				atRuleComplexities.push(complexity)
@@ -858,6 +861,7 @@ function analyzeInternal<T extends boolean>(css: string, options: Options, useLo
 			}),
 			layer: layers.c(),
 			property: registeredProperties.c(),
+			scope: scopes.c(),
 			complexity: atRuleComplexity,
 			nesting: assign(
 				atruleNesting.aggregate(),