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

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+import assert from "node:assert";
+import { describe, test } from "node:test";
+import FunctionTree from "../../src/drivers/FunctionTree.js";
+import { Tree } from "../../src/internal.js";
+import concat from "../../src/operations/concat.js";
+
+describe("concat", () => {
+  test("concatenates deep tree values", async () => {
+    const tree = Tree.from({
+      a: "A",
+      b: "B",
+      c: "C",
+      more: {
+        d: "D",
+        e: "E",
+      },
+    });
+    const result = await concat.call(null, tree);
+    assert.equal(result, "ABCDE");
+  });
+
+  test("concatenates deep tree-like values", async () => {
+    const letters = ["a", "b", "c"];
+    const specimens = new FunctionTree(
+      (letter) => ({
+        lowercase: letter,
+        uppercase: letter.toUpperCase(),
+      }),
+      letters
+    );
+    const result = await concat.call(null, specimens);
+    assert.equal(result, "aAbBcC");
+  });
+});