1 files changed, 389 insertions, 0 deletions
diff --git a/node_modules/csso/lib/utils/list.js b/node_modules/csso/lib/utils/list.js
new file mode 100644
index 00000000..30d14871
--- /dev/null
+++ b/node_modules/csso/lib/utils/list.js
@@ -0,0 +1,389 @@
+//
+//            item        item        item        item
+//          /------\    /------\    /------\    /------\
+//          | data |    | data |    | data |    | data |
+//  null <--+-prev |<---+-prev |<---+-prev |<---+-prev |
+//          | next-+--->| next-+--->| next-+--->| next-+--> null
+//          \------/    \------/    \------/    \------/
+//             ^                                    ^
+//             |                list                |
+//             |              /------\              |
+//             \--------------+-head |              |
+//                            | tail-+--------------/
+//                            \------/
+//
+
+function createItem(data) {
+    return {
+        data: data,
+        next: null,
+        prev: null
+    };
+}
+
+var List = function(values) {
+    this.cursor = null;
+    this.head = null;
+    this.tail = null;
+
+    if (Array.isArray(values)) {
+        var cursor = null;
+
+        for (var i = 0; i < values.length; i++) {
+            var item = createItem(values[i]);
+
+            if (cursor !== null) {
+                cursor.next = item;
+            } else {
+                this.head = item;
+            }
+
+            item.prev = cursor;
+            cursor = item;
+        }
+
+        this.tail = cursor;
+    }
+};
+
+Object.defineProperty(List.prototype, 'size', {
+    get: function() {
+        var size = 0;
+        var cursor = this.head;
+
+        while (cursor) {
+            size++;
+            cursor = cursor.next;
+        }
+
+        return size;
+    }
+});
+
+List.createItem = createItem;
+List.prototype.createItem = createItem;
+
+List.prototype.toArray = function() {
+    var cursor = this.head;
+    var result = [];
+
+    while (cursor) {
+        result.push(cursor.data);
+        cursor = cursor.next;
+    }
+
+    return result;
+};
+List.prototype.toJSON = function() {
+    return this.toArray();
+};
+
+List.prototype.isEmpty = function() {
+    return this.head === null;
+};
+
+List.prototype.first = function() {
+    return this.head && this.head.data;
+};
+
+List.prototype.last = function() {
+    return this.tail && this.tail.data;
+};
+
+List.prototype.each = function(fn, context) {
+    var item;
+    var cursor = {
+        prev: null,
+        next: this.head,
+        cursor: this.cursor
+    };
+
+    if (context === undefined) {
+        context = this;
+    }
+
+    // push cursor
+    this.cursor = cursor;
+
+    while (cursor.next !== null) {
+        item = cursor.next;
+        cursor.next = item.next;
+
+        fn.call(context, item.data, item, this);
+    }
+
+    // pop cursor
+    this.cursor = this.cursor.cursor;
+};
+
+List.prototype.eachRight = function(fn, context) {
+    var item;
+    var cursor = {
+        prev: this.tail,
+        next: null,
+        cursor: this.cursor
+    };
+
+    if (context === undefined) {
+        context = this;
+    }
+
+    // push cursor
+    this.cursor = cursor;
+
+    while (cursor.prev !== null) {
+        item = cursor.prev;
+        cursor.prev = item.prev;
+
+        fn.call(context, item.data, item, this);
+    }
+
+    // pop cursor
+    this.cursor = this.cursor.cursor;
+};
+
+List.prototype.nextUntil = function(start, fn, context) {
+    if (start === null) {
+        return;
+    }
+
+    var item;
+    var cursor = {
+        prev: null,
+        next: start,
+        cursor: this.cursor
+    };
+
+    if (context === undefined) {
+        context = this;
+    }
+
+    // push cursor
+    this.cursor = cursor;
+
+    while (cursor.next !== null) {
+        item = cursor.next;
+        cursor.next = item.next;
+
+        if (fn.call(context, item.data, item, this)) {
+            break;
+        }
+    }
+
+    // pop cursor
+    this.cursor = this.cursor.cursor;
+};
+
+List.prototype.prevUntil = function(start, fn, context) {
+    if (start === null) {
+        return;
+    }
+
+    var item;
+    var cursor = {
+        prev: start,
+        next: null,
+        cursor: this.cursor
+    };
+
+    if (context === undefined) {
+        context = this;
+    }
+
+    // push cursor
+    this.cursor = cursor;
+
+    while (cursor.prev !== null) {
+        item = cursor.prev;
+        cursor.prev = item.prev;
+
+        if (fn.call(context, item.data, item, this)) {
+            break;
+        }
+    }
+
+    // pop cursor
+    this.cursor = this.cursor.cursor;
+};
+
+List.prototype.some = function(fn, context) {
+    var cursor = this.head;
+
+    if (context === undefined) {
+        context = this;
+    }
+
+    while (cursor !== null) {
+        if (fn.call(context, cursor.data, cursor, this)) {
+            return true;
+        }
+
+        cursor = cursor.next;
+    }
+
+    return false;
+};
+
+List.prototype.map = function(fn, context) {
+    var result = [];
+    var cursor = this.head;
+
+    if (context === undefined) {
+        context = this;
+    }
+
+    while (cursor !== null) {
+        result.push(fn.call(context, cursor.data, cursor, this));
+        cursor = cursor.next;
+    }
+
+    return result;
+};
+
+List.prototype.copy = function() {
+    var result = new List();
+    var cursor = this.head;
+
+    while (cursor !== null) {
+        result.insert(createItem(cursor.data));
+        cursor = cursor.next;
+    }
+
+    return result;
+};
+
+List.prototype.updateCursors = function(prevOld, prevNew, nextOld, nextNew) {
+    var cursor = this.cursor;
+
+    while (cursor !== null) {
+        if (prevNew === true || cursor.prev === prevOld) {
+            cursor.prev = prevNew;
+        }
+
+        if (nextNew === true || cursor.next === nextOld) {
+            cursor.next = nextNew;
+        }
+
+        cursor = cursor.cursor;
+    }
+};
+
+List.prototype.insert = function(item, before) {
+    if (before !== undefined && before !== null) {
+        // prev   before
+        //      ^
+        //     item
+        this.updateCursors(before.prev, item, before, item);
+
+        if (before.prev === null) {
+            // insert to the beginning of list
+            if (this.head !== before) {
+                throw new Error('before doesn\'t below to list');
+            }
+
+            // since head points to before therefore list doesn't empty
+            // no need to check tail
+            this.head = item;
+            before.prev = item;
+            item.next = before;
+
+            this.updateCursors(null, item);
+        } else {
+
+            // insert between two items
+            before.prev.next = item;
+            item.prev = before.prev;
+
+            before.prev = item;
+            item.next = before;
+        }
+    } else {
+        // tail
+        //      ^
+        //     item
+        this.updateCursors(this.tail, item, null, item);
+
+        // insert to end of the list
+        if (this.tail !== null) {
+            // if list has a tail, then it also has a head, but head doesn't change
+
+            // last item -> new item
+            this.tail.next = item;
+
+            // last item <- new item
+            item.prev = this.tail;
+        } else {
+            // if list has no a tail, then it also has no a head
+            // in this case points head to new item
+            this.head = item;
+        }
+
+        // tail always start point to new item
+        this.tail = item;
+    }
+};
+
+List.prototype.remove = function(item) {
+    //      item
+    //       ^
+    // prev     next
+    this.updateCursors(item, item.prev, item, item.next);
+
+    if (item.prev !== null) {
+        item.prev.next = item.next;
+    } else {
+        if (this.head !== item) {
+            throw new Error('item doesn\'t below to list');
+        }
+
+        this.head = item.next;
+    }
+
+    if (item.next !== null) {
+        item.next.prev = item.prev;
+    } else {
+        if (this.tail !== item) {
+            throw new Error('item doesn\'t below to list');
+        }
+
+        this.tail = item.prev;
+    }
+
+    item.prev = null;
+    item.next = null;
+
+    return item;
+};
+
+List.prototype.appendList = function(list) {
+    // ignore empty lists
+    if (list.head === null) {
+        return;
+    }
+
+    this.updateCursors(this.tail, list.tail, null, list.head);
+
+    // insert to end of the list
+    if (this.tail !== null) {
+        // if destination list has a tail, then it also has a head,
+        // but head doesn't change
+
+        // dest tail -> source head
+        this.tail.next = list.head;
+
+        // dest tail <- source head
+        list.head.prev = this.tail;
+    } else {
+        // if list has no a tail, then it also has no a head
+        // in this case points head to new item
+        this.head = list.head;
+    }
+
+    // tail always start point to new item
+    this.tail = list.tail;
+
+    list.head = null;
+    list.tail = null;
+};
+
+module.exports = List;