add support heartbeat to couchdb-changes-stream

packages/couchdb-changes-stream/tests/CouchDBChangesStream-EventSourceFormat.test.ts

@@ -0,0 +1,56 @@
+import {
+  CouchDBChangesStream,
+  CouchDBChange,
+} from "../src/CouchDBChangesStream";
+
+describe("CouchDBChangesStream - EventSource Format", () => {
+  it("should parse changes from text/event-stream format correctly", async () => {
+    const eventSourceData = `
+event: change
+data: {"seq":1,"id":"doc1","changes":[{"rev":"1-abc"}]}
+
+event: change
+data: {"seq":2,"id":"doc2","changes":[{"rev":"2-def"}]}
+
+event: change
+data: {"seq":3,"id":"doc3","changes":[{"rev":"3-ghi"}]}
+`;
+
+    const mockResponse: Partial<Response> = {
+      ok: true,
+      status: 200,
+      headers: new Headers({ "Content-Type": "text/event-stream" }),
+      body: new ReadableStream({
+        start(controller) {
+          controller.enqueue(new TextEncoder().encode(eventSourceData));
+          controller.close();
+        },
+      }),
+    };
+
+    const mockFetch = jest.fn(async () => mockResponse as Response);
+
+    const stream = new CouchDBChangesStream<any>("http://mock-couchdb", {
+      feed: "eventsource",
+      fetch: mockFetch,
+    });
+
+    const result: CouchDBChange<any>[] = [];
+    for await (const change of stream) {
+      result.push(change);
+    }
+
+    // Ожидаемый результат
+    const expectedChanges: CouchDBChange<any>[] = [
+      { seq: 1, id: "doc1", changes: [{ rev: "1-abc" }] },
+      { seq: 2, id: "doc2", changes: [{ rev: "2-def" }] },
+      { seq: 3, id: "doc3", changes: [{ rev: "3-ghi" }] },
+    ];
+
+    // Проверяем, что результат соответствует ожидаемым изменениям
+    expect(result).toEqual(expectedChanges);
+
+    // Проверяем, что fetch был вызван
+    expect(mockFetch).toHaveBeenCalledTimes(1);
+  });
+});