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node_modules/@weborigami/language/test/runtime/mergeTrees.test.js

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+import { Tree } from "@weborigami/async-tree";
+import assert from "node:assert";
+import { describe, test } from "node:test";
+import mergeTrees from "../../src/runtime/mergeTrees.js";
+
+describe("mergeTrees", () => {
+  test("merges trees", async () => {
+    const tree = await mergeTrees.call(
+      null,
+      {
+        a: 1,
+        b: 2,
+      },
+      {
+        b: 3,
+        c: 4,
+      }
+    );
+    // @ts-ignore
+    assert.deepEqual(await Tree.plain(tree), {
+      a: 1,
+      b: 3,
+      c: 4,
+    });
+  });
+
+  test("if all arguments are plain objects, result is a plain object", async () => {
+    const result = await mergeTrees.call(
+      null,
+      {
+        a: 1,
+        b: 2,
+      },
+      {
+        b: 3,
+        c: 4,
+      }
+    );
+    assert.deepEqual(result, {
+      a: 1,
+      b: 3,
+      c: 4,
+    });
+  });
+
+  test("if all arguments are arrays, result is an array", async () => {
+    const result = await mergeTrees.call(null, [1, 2], [3, 4]);
+    assert.deepEqual(result, [1, 2, 3, 4]);
+  });
+});