code fmt and CI

.editorconfig

@@ -0,0 +1,15 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+indent_style = tab
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.md]
+trim_trailing_whitespace = false
+
+[*.yml]
+indent_size = 2
+indent_style = space

.github/workflows/test.yml

@@ -0,0 +1,37 @@
+name: test
+on:
+  push:
+    branches:
+    - 'main'
+    - 'master'
+  pull_request:
+  workflow_dispatch:
+
+defaults:
+  run:
+    shell: bash
+
+jobs:
+  test:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      # Test node 14/16/18/20/22 on ubuntu
+      # Test node 20 on macos/windows
+      # Enable annotations only for node 20 + ubuntu
+      matrix:
+        os: [ubuntu-latest]
+        node: [16, 18, 20, 22]
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 1
+      - uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node }}
+
+      - name: npm ci
+        run: npm ci
+
+      - name: test
+        run: npm run test

LICENSE

@@ -1,6 +1,7 @@
 The MIT License (MIT)
 
 Copyright (c) 2016 David Clark
+Copyright © CSSTools Contributors
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

index.js

@@ -1,25 +1,25 @@
 module.exports = function resolveNestedSelector(selector, node) {
-  var parent = node.parent;
-  var parentIsNestAtRule = parent.type === 'atrule' && parent.name === 'nest';
+	var parent = node.parent;
+	var parentIsNestAtRule = parent.type === 'atrule' && parent.name === 'nest';
 
-  if (parent.type === 'root') return [selector];
-  if (parent.type !== 'rule' && !parentIsNestAtRule) return resolveNestedSelector(selector, parent);
+	if (parent.type === 'root') return [selector];
+	if (parent.type !== 'rule' && !parentIsNestAtRule) return resolveNestedSelector(selector, parent);
 
-  var parentSelectors = (parentIsNestAtRule)
-    ? parent.params.split(',').map(function(s) { return s.trim(); })
-    : parent.selectors;
+	var parentSelectors = (parentIsNestAtRule)
+		? parent.params.split(',').map(function(s) { return s.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 result.concat(newlyResolvedSelectors);
-    }
+	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 result.concat(newlyResolvedSelectors);
+		}
 
-    var combinedSelector = [ parentSelector, selector ].join(' ');
-    return result.concat(resolveNestedSelector(combinedSelector, parent));
-  }, []);
+		var combinedSelector = [ parentSelector, selector ].join(' ');
+		return result.concat(resolveNestedSelector(combinedSelector, parent));
+	}, []);
 
-  return resolvedSelectors;
+	return resolvedSelectors;
 }