fix: build

packages/collection-utils/src/tree-group.ts

@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2022 StApps
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+export type Tree<T> = {
+  [key: string]: Tree<T>;
+} & {
+  _?: T[] | undefined;
+};
+
+/**
+ *
+ */
+export function treeGroupBy<T>(items: T[], transform: (item: T) => string[]): Tree<T> {
+  const tree: Tree<T> = {};
+
+  for (const item of items) {
+    let currentTree = tree;
+    const keys = transform(item);
+    if (keys.length === 0) {
+      currentTree._ = currentTree._ || [];
+      currentTree._.push(item);
+    }
+    // eslint-disable-next-line unicorn/no-array-for-each
+    keys.forEach((key, i) => {
+      currentTree = currentTree[key] = (currentTree[key] ?? {}) as Tree<T>;
+      if (i === keys.length - 1) {
+        currentTree._ = currentTree._ ?? [];
+        // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+        currentTree._.push(item);
+      }
+    });
+  }
+
+  return tree;
+}