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node_modules/@weborigami/async-tree/test/operations/group.test.js

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+import assert from "node:assert";
+import { describe, test } from "node:test";
+import { Tree } from "../../src/internal.js";
+import group from "../../src/operations/group.js";
+
+describe("group transform", () => {
+  test("groups an array using a group key function", async () => {
+    const fonts = [
+      { name: "Aboreto", tags: ["Sans Serif"] },
+      { name: "Albert Sans", tags: ["Geometric", "Sans Serif"] },
+      { name: "Alegreya", tags: ["Serif"] },
+      { name: "Work Sans", tags: ["Grotesque", "Sans Serif"] },
+    ];
+    const tree = Tree.from(fonts);
+    const grouped = await group(tree, (value, key, tree) => value.tags);
+    assert.deepEqual(await Tree.plain(grouped), {
+      Geometric: [{ name: "Albert Sans", tags: ["Geometric", "Sans Serif"] }],
+      Grotesque: [{ name: "Work Sans", tags: ["Grotesque", "Sans Serif"] }],
+      "Sans Serif": [
+        { name: "Aboreto", tags: ["Sans Serif"] },
+        { name: "Albert Sans", tags: ["Geometric", "Sans Serif"] },
+        { name: "Work Sans", tags: ["Grotesque", "Sans Serif"] },
+      ],
+      Serif: [{ name: "Alegreya", tags: ["Serif"] }],
+    });
+  });
+
+  test("groups an object using a group key function", async () => {
+    const fonts = {
+      Aboreto: { tags: ["Sans Serif"] },
+      "Albert Sans": { tags: ["Geometric", "Sans Serif"] },
+      Alegreya: { tags: ["Serif"] },
+      "Work Sans": { tags: ["Grotesque", "Sans Serif"] },
+    };
+    const tree = Tree.from(fonts);
+    const grouped = await group(tree, (value, key, tree) => value.tags);
+    assert.deepEqual(await Tree.plain(grouped), {
+      Geometric: {
+        "Albert Sans": { tags: ["Geometric", "Sans Serif"] },
+      },
+      Grotesque: {
+        "Work Sans": { tags: ["Grotesque", "Sans Serif"] },
+      },
+      "Sans Serif": {
+        Aboreto: { tags: ["Sans Serif"] },
+        "Albert Sans": { tags: ["Geometric", "Sans Serif"] },
+        "Work Sans": { tags: ["Grotesque", "Sans Serif"] },
+      },
+      Serif: {
+        Alegreya: { tags: ["Serif"] },
+      },
+    });
+  });
+});