Implement Parallel ujsx component with id and maxConcurrency props

src/component/index.ts

@@ -1 +1,2 @@
-export {};
+export { Parallel } from "./parallel.js";
+export type { ParallelProps } from "./parallel.js";

src/component/parallel.ts

@@ -1 +1,26 @@
-export {};
+import type { UComponent, UElement, UNode, UniversalProps } from "@alkdev/ujsx";
+
+export interface ParallelProps extends UniversalProps {
+  id?: string;
+  maxConcurrency?: number;
+}
+
+export const Parallel: UComponent<ParallelProps> = (
+  props: ParallelProps & { children?: UNode[] },
+): UElement => {
+  const { id, maxConcurrency, children, ...rest } = props;
+  const elementProps: UniversalProps = { ...rest };
+  if (id !== undefined) {
+    elementProps.id = id;
+  }
+  if (maxConcurrency !== undefined) {
+    elementProps.maxConcurrency = maxConcurrency;
+  }
+  return {
+    type: "parallel",
+    props: elementProps,
+    children: children ?? [],
+  };
+};
+
+Parallel.displayName = "Parallel";

test/component/components.test.ts

@@ -1,7 +1,33 @@
-import { describe, it, expect } from 'vitest';
+import { describe, it, expect } from "vitest";
+import { Parallel } from "../../src/component/parallel.js";
+import type { ParallelProps } from "../../src/component/parallel.js";
+import type { UElement, UNode } from "@alkdev/ujsx";
 
-describe('components', () => {
-  it('placeholder', () => {
-    expect(true).toBe(true);
+describe("Parallel", () => {
+  it("produces UElement with type parallel", () => {
+    const el = Parallel({} as ParallelProps & { children?: UNode[] });
+    expect(el.type).toBe("parallel");
+    expect(el.children).toEqual([]);
+  });
+
+  it("preserves id prop", () => {
+    const el = Parallel({ id: "group-1" } as ParallelProps & { children?: UNode[] });
+    expect((el as UElement).props.id).toBe("group-1");
+  });
+
+  it("preserves maxConcurrency prop", () => {
+    const el = Parallel({ maxConcurrency: 3 } as ParallelProps & { children?: UNode[] });
+    expect((el as UElement).props.maxConcurrency).toBe(3);
+  });
+
+  it("includes children", () => {
+    const el = Parallel({ children: ["child1", "child2"] } as ParallelProps & { children?: UNode[] });
+    expect(el.children).toEqual(["child1", "child2"]);
+  });
+
+  it("omits id and maxConcurrency when not provided", () => {
+    const el = Parallel({} as ParallelProps & { children?: UNode[] });
+    expect((el as UElement).props.id).toBeUndefined();
+    expect((el as UElement).props.maxConcurrency).toBeUndefined();
   });
 });