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node_modules/@weborigami/async-tree/test/drivers/FunctionTree.test.js

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+import assert from "node:assert";
+import { describe, test } from "node:test";
+import FunctionTree from "../../src/drivers/FunctionTree.js";
+
+describe("FunctionTree", async () => {
+  test("can get the keys of the tree", async () => {
+    const fixture = createFixture();
+    assert.deepEqual(Array.from(await fixture.keys()), [
+      "Alice.md",
+      "Bob.md",
+      "Carol.md",
+    ]);
+  });
+
+  test("can get the value for a key", async () => {
+    const fixture = createFixture();
+    const alice = await fixture.get("Alice.md");
+    assert.equal(alice, "Hello, **Alice**.");
+  });
+
+  test("getting a value from function with multiple arguments curries the function", async () => {
+    const fixture = new FunctionTree((a, b, c) => a + b + c);
+    const fnA = await fixture.get(1);
+    const fnAB = await fnA.get(2);
+    const result = await fnAB.get(3);
+    assert.equal(result, 6);
+  });
+
+  test("getting an unsupported key returns undefined", async () => {
+    const fixture = createFixture();
+    assert.equal(await fixture.get("xyz"), undefined);
+  });
+});
+
+function createFixture() {
+  return new FunctionTree(
+    (key) => {
+      if (key?.endsWith?.(".md")) {
+        const name = key.slice(0, -3);
+        return `Hello, **${name}**.`;
+      }
+      return undefined;
+    },
+    ["Alice.md", "Bob.md", "Carol.md"]
+  );
+}