feat(marketing-pages): add getPageBySlugUseCase (test red until DI lands)

packages/marketing-pages/src/application/use-cases/get-page-by-slug.use-case.test.ts

@@ -0,0 +1,30 @@
+import { beforeEach, describe, expect, it } from "vitest";
+import { marketingPagesContainer } from "@/di/container";
+import { MARKETING_PAGES_SYMBOLS } from "@/di/symbols";
+import { MockPagesRepository } from "@/infrastructure/repositories/mock-pages.repository";
+import type { IPagesRepository } from "@/application/repositories/pages-repository.interface";
+import { getPageBySlugUseCase } from "./get-page-by-slug.use-case";
+
+describe("getPageBySlugUseCase", () => {
+  let repo: MockPagesRepository;
+
+  beforeEach(() => {
+    if (marketingPagesContainer.isBound(MARKETING_PAGES_SYMBOLS.IPagesRepository)) {
+      marketingPagesContainer.unbind(MARKETING_PAGES_SYMBOLS.IPagesRepository);
+    }
+    repo = new MockPagesRepository();
+    marketingPagesContainer
+      .bind<IPagesRepository>(MARKETING_PAGES_SYMBOLS.IPagesRepository)
+      .toConstantValue(repo);
+  });
+
+  it("returns the page when found", async () => {
+    const result = await getPageBySlugUseCase("about");
+    expect(result?.slug).toBe("about");
+  });
+
+  it("returns undefined when not found", async () => {
+    const result = await getPageBySlugUseCase("missing-page");
+    expect(result).toBeUndefined();
+  });
+});

packages/marketing-pages/src/application/use-cases/get-page-by-slug.use-case.ts

@@ -0,0 +1,13 @@
+import type { Page } from "../../entities/page";
+import { marketingPagesContainer } from "../../di/container";
+import { MARKETING_PAGES_SYMBOLS } from "../../di/symbols";
+import type { IPagesRepository } from "../repositories/pages-repository.interface";
+
+export async function getPageBySlugUseCase(
+  slug: string,
+): Promise<Page | undefined> {
+  const repo = marketingPagesContainer.get<IPagesRepository>(
+    MARKETING_PAGES_SYMBOLS.IPagesRepository,
+  );
+  return repo.getPageBySlug(slug);
+}