correctly split atrule preludes

Author: romainmenke

index.js

@@ -6,7 +6,7 @@ module.exports = function resolveNestedSelector(selector, node) {
 	if (parent.type !== 'rule' && !parentIsNestAtRule) return resolveNestedSelector(selector, parent);
 
 	var parentSelectors = (parentIsNestAtRule)
-		? parent.params.split(',').map(function(s) { return s.trim(); })
+		? list(parent.params)
 		: parent.selectors;
 
 	var resolvedSelectors = parentSelectors.reduce(function(result, parentSelector) {
@@ -23,3 +23,48 @@ module.exports = function resolveNestedSelector(selector, node) {
 
 	return resolvedSelectors;
 }
+
+// https://github.com/postcss/postcss/blob/main/lib/list.js#L1
+// We should not have `postcss` as a direct dependency so, we inline the same code here.
+function list(string) {
+	let array = []
+	let current = ''
+	let split = false
+
+	let func = 0
+	let inQuote = false
+	let prevQuote = ''
+	let escape = false
+
+	for (let letter of string) {
+		if (escape) {
+			escape = false
+		} else if (letter === '\\') {
+			escape = true
+		} else if (inQuote) {
+			if (letter === prevQuote) {
+				inQuote = false
+			}
+		} else if (letter === '"' || letter === "'") {
+			inQuote = true
+			prevQuote = letter
+		} else if (letter === '(') {
+			func += 1
+		} else if (letter === ')') {
+			if (func > 0) func -= 1
+		} else if (func === 0) {
+			if (letter === ',') split = true
+		}
+
+		if (split) {
+			if (current !== '') array.push(current.trim())
+			current = ''
+			split = false
+		} else {
+			current += letter
+		}
+	}
+
+	if (current !== '') array.push(current.trim())
+	return array
+}

package-lock.json

@@ -1,6 +1,6 @@
 {
 	"name": "postcss-resolve-nested-selector",
-	"version": "0.1.2",
+	"version": "0.1.3",
 	"description": "Resolve a nested selector in a PostCSS AST",
 	"main": "index.js",
 	"scripts": {

package.json

@@ -57,3 +57,51 @@ test(async t => {
 		['.foo:hover > b', '.foo_bar > b'],
 	);
 });
+
+test(async t => {
+	const code = `.a { .b:is(:hover, :focus) & {} }`;
+	assert.deepEqual(
+		await util.resolveChosenSelector(code, '.b:is(:hover, :focus) &'),
+		['.b:is(:hover, :focus) .a'],
+	);
+});
+
+test(async t => {
+	const code = `.a { .b:is(:hover, :focus) & { & .c {} } }`;
+	assert.deepEqual(
+		await util.resolveChosenSelector(code, '& .c'),
+		['.b:is(:hover, :focus) .a .c'],
+	);
+});
+
+test(async t => {
+	const code = `.a {
+		@nest .b:not(:hover, :focus) & {
+			& .c {
+				color: red;
+			}
+		}
+	}`;
+	assert.deepEqual(
+		await util.resolveChosenSelector(code, '& .c'),
+		['.b:not(:hover, :focus) .a .c'],
+	);
+});
+
+test(async t => {
+	const code = `.a {
+		@nest .b & , & .c , & .d & {
+			& .e {
+				color: red;
+			}
+		}
+	}`;
+	assert.deepEqual(
+		await util.resolveChosenSelector(code, '& .e'),
+		[
+			'.a .c .e',
+			'.a .d .a .e',
+			'.b .a .e'
+		],
+	);
+});