improve splitting by comma and replacing &

index.js

@@ -6,13 +6,13 @@ module.exports = function resolveNestedSelector(selector, node) {
 	if (parent.type !== 'rule' && !parentIsNestAtRule) return resolveNestedSelector(selector, parent);
 
 	var parentSelectors = (parentIsNestAtRule)
-		? list(parent.params)
+		? split(parent.params, ',', false).map((x) => x.trim())
 		: parent.selectors;
 
 	var resolvedSelectors = parentSelectors.reduce(function(result, parentSelector) {
 		if (selector.indexOf('&') !== -1) {
 			var newlyResolvedSelectors = resolveNestedSelector(parentSelector, parent).map(function(resolvedParentSelector) {
-				return selector.replace(/&/g, resolvedParentSelector);
+				return split(selector, '&', true).join(resolvedParentSelector);
 			});
 			return result.concat(newlyResolvedSelectors);
 		}
@@ -24,17 +24,20 @@ 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
+function split(string, separator, splitFunctions) {
+	var blockPairs = {
+		'(': ')',
+		'[': ']',
+		'{': '}'
+	}
+	var array = []
+	var current = ''
+	var split = false
 
-	let func = 0
-	let inQuote = false
-	let prevQuote = ''
-	let escape = false
+	var blockClose = []
+	var inQuote = false
+	var prevQuote = ''
+	var escape = false
 
 	for (let letter of string) {
 		if (escape) {
@@ -48,23 +51,23 @@ function list(string) {
 		} 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
+		} else if (letter === '(' || letter === '[' || letter === '{') {
+			blockClose.push(blockPairs[letter])
+		} else if (letter === blockClose[blockClose.length - 1]) {
+			blockClose.pop()
+		} else if (blockClose.length === 0 || (splitFunctions && blockClose.every((x) => x === ')'))) {
+			if (letter === separator) split = true
 		}
 
 		if (split) {
-			if (current !== '') array.push(current.trim())
+			array.push(current)
 			current = ''
 			split = false
 		} else {
 			current += letter
 		}
 	}
 
-	if (current !== '') array.push(current.trim())
+	array.push(current)
 	return array
 }

package.json

@@ -1,6 +1,6 @@
 {
 	"name": "postcss-resolve-nested-selector",
-	"version": "0.1.3",
+	"version": "0.1.4",
 	"description": "Resolve a nested selector in a PostCSS AST",
 	"main": "index.js",
 	"scripts": {

test/api.test.mjs

@@ -88,6 +88,48 @@ test(async t => {
 	);
 });
 
+test(async t => {
+	const code = `.a {
+		@nest [a=,] & {
+			& .c {
+				color: red;
+			}
+		}
+	}`;
+	assert.deepEqual(
+		await util.resolveChosenSelector(code, '& .c'),
+		['[a=,] .a .c'],
+	);
+});
+
+test(async t => {
+	const code = `.a {
+		@nest a \\, & {
+			& .c {
+				color: red;
+			}
+		}
+	}`;
+	assert.deepEqual(
+		await util.resolveChosenSelector(code, '& .c'),
+		['a \\, .a .c'],
+	);
+});
+
+test(async t => {
+	const code = `.a {
+		@nest [a=","] & {
+			& .c {
+				color: red;
+			}
+		}
+	}`;
+	assert.deepEqual(
+		await util.resolveChosenSelector(code, '& .c'),
+		['[a=","] .a .c'],
+	);
+});
+
 test(async t => {
 	const code = `.a {
 		@nest .b & , & .c , & .d & {
@@ -105,3 +147,39 @@ test(async t => {
 		],
 	);
 });
+
+test(async t => {
+	const code = `.a {
+		.b [c="&"] & {}
+	}`;
+	assert.deepEqual(
+		await util.resolveChosenSelector(code, '.b [c="&"] &'),
+		[
+			'.b [c="&"] .a'
+		],
+	);
+});
+
+test(async t => {
+	const code = `.a {
+		.b [c=&] & {}
+	}`;
+	assert.deepEqual(
+		await util.resolveChosenSelector(code, '.b [c=&] &'),
+		[
+			'.b [c=&] .a'
+		],
+	);
+});
+
+test(async t => {
+	const code = `.a {
+		.b \\& + & {
+			& .c {}
+		}
+	}`;
+	assert.deepEqual(
+		await util.resolveChosenSelector(code, '& .c'),
+		['.b \\& + .a .c'],
+	);
+});