test(common): unit tests for http/testing expectOne (#27005)

PR Close #27005

packages/common/http/testing/test/request_spec.ts

@@ -22,4 +22,40 @@ describe('HttpClient TestRequest', () => {
 
     expect(resp).toBeNull();
   });
+
+  it('throws if no request matches', () => {
+    const mock = new HttpClientTestingBackend();
+    const client = new HttpClient(mock);
+
+    let resp: any;
+    client.get('/some-other-url').subscribe(body => { resp = body; });
+
+    try {
+      // expect different URL
+      mock.expectOne('/some-url').flush(null);
+      fail();
+    } catch (error) {
+      expect(error.message)
+          .toBe('Expected one matching request for criteria "Match URL: /some-url", found none.');
+    }
+  });
+
+  it('throws if no request matches the exact parameters', () => {
+    const mock = new HttpClientTestingBackend();
+    const client = new HttpClient(mock);
+
+    let resp: any;
+    const params = {query: 'hello'};
+    client.get('/some-url', {params}).subscribe(body => { resp = body; });
+
+    try {
+      // expect different query parameters
+      mock.expectOne('/some-url?query=world').flush(null);
+      fail();
+    } catch (error) {
+      expect(error.message)
+          .toBe(
+              'Expected one matching request for criteria "Match URL: /some-url?query=world", found none.');
+    }
+  });
 });