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

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+import { ObjectTree } from "@weborigami/async-tree";
+import assert from "node:assert";
+import { describe, test } from "node:test";
+import * as ops from "../../src/runtime/ops.js";
+
+import evaluate from "../../src/runtime/evaluate.js";
+
+describe("evaluate", () => {
+  test("can retrieve values from scope", async () => {
+    const code = createCode([ops.scope, "message"]);
+    const parent = new ObjectTree({
+      message: "Hello",
+    });
+    const tree = new ObjectTree({});
+    tree.parent = parent;
+    const result = await evaluate.call(tree, code);
+    assert.equal(result, "Hello");
+  });
+
+  test("can invoke functions in scope", async () => {
+    // Match the array representation of code generated by the parser.
+    const code = createCode([
+      [ops.scope, "greet"],
+      [ops.scope, "name"],
+    ]);
+
+    const tree = new ObjectTree({
+      async greet(name) {
+        return `Hello ${name}`;
+      },
+      name: "world",
+    });
+
+    const result = await evaluate.call(tree, code);
+    assert.equal(result, "Hello world");
+  });
+
+  test("passes context to invoked functions", async () => {
+    const code = createCode([ops.scope, "fn"]);
+    const tree = new ObjectTree({
+      async fn() {
+        assert.equal(this, tree);
+      },
+    });
+    await evaluate.call(tree, code);
+  });
+
+  test("evaluates a function with fixed number of arguments", async () => {
+    const fn = (x, y) => ({
+      c: `${x}${y}c`,
+    });
+    const code = createCode([ops.traverse, fn, "a", "b", "c"]);
+    assert.equal(await evaluate.call(null, code), "abc");
+  });
+
+  test("if object in function position isn't a function, can unpack it", async () => {
+    const fn = (...args) => args.join(",");
+    const packed = new String();
+    /** @type {any} */ (packed).unpack = async () => fn;
+    const code = createCode([packed, "a", "b", "c"]);
+    const result = await evaluate.call(null, code);
+    assert.equal(result, "a,b,c");
+  });
+
+  test("by defalut sets the parent of a returned tree to the current tree", async () => {
+    const fn = () => new ObjectTree({});
+    const code = createCode([fn]);
+    const tree = new ObjectTree({});
+    const result = await evaluate.call(tree, code);
+    assert.equal(result.parent, tree);
+  });
+});
+
+/**
+ * @returns {import("../../index.ts").Code}
+ */
+function createCode(array) {
+  const code = array;
+  /** @type {any} */ (code).location = {
+    source: {
+      text: "",
+    },
+  };
+  return code;
+}