Preserve lowLevelHttpRequest, so that it's available to tests.

When lowLevelHttpRequest is not set via MockHttpTransport.Builder, buildRequest() creates a new instance of MockLowLevelHttpTransport. Due to what seems to be a bug, the newly created MLLHT wasn't saved to MHT instance. That means, getLowLevelHttpRequest() called on such instance returns null, making it impossible to inspect actual request being sent. For example, this bug made it impossible to verify headers of outbound HTTP requests.

Author: pawelz

google-http-client/pom.xml

@@ -150,6 +150,11 @@
       <artifactId>junit</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>com.google.truth</groupId>
+      <artifactId>truth</artifactId>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>org.mockito</groupId>
       <artifactId>mockito-all</artifactId>

google-http-client/src/main/java/com/google/api/client/testing/http/MockHttpTransport.java

@@ -81,11 +81,11 @@ public LowLevelHttpRequest buildRequest(String method, String url) throws IOExce
     if (lowLevelHttpRequest != null) {
       return lowLevelHttpRequest;
     }
-    MockLowLevelHttpRequest request = new MockLowLevelHttpRequest(url);
+    lowLevelHttpRequest = new MockLowLevelHttpRequest(url);
     if (lowLevelHttpResponse != null) {
-      request.setResponse(lowLevelHttpResponse);
+      lowLevelHttpRequest.setResponse(lowLevelHttpResponse);
     }
-    return request;
+    return lowLevelHttpRequest;
   }
 
   /**

google-http-client/src/test/java/com/google/api/client/testing/http/MockHttpTransportTest.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2013 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+package com.google.api.client.testing.http;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.api.client.http.GenericUrl;
+import com.google.api.client.http.HttpRequest;
+import com.google.api.client.http.HttpRequestFactory;
+
+import junit.framework.TestCase;
+
+/**
+ * Tests {@link MockHttpTransport}.
+ *
+ * @author Paweł Zuzelski
+ */
+public final class MockHttpTransportTest extends TestCase {
+  // The purpose of this test is to verify, that the actual lowLevelHttpRequest used is preserved
+  // so that the content of the request can be verified in tests.
+  public void testBuildGetRequest_preservesLoLevelHttpRequest() throws Exception {
+    MockHttpTransport httpTransport = new MockHttpTransport();
+    GenericUrl url = new GenericUrl("http://example.org");
+    HttpRequestFactory requestFactory = httpTransport.createRequestFactory();
+    HttpRequest request = requestFactory.buildGetRequest(url);
+    request.getHeaders().set("foo", "bar");
+    Object unusedOnlyInspectingSideEffects = request.execute();
+    MockLowLevelHttpRequest actualRequest = httpTransport.getLowLevelHttpRequest();
+    assertThat(actualRequest.getHeaders()).containsKey("foo");
+    assertThat(actualRequest.getHeaders().get("foo")).containsExactly("bar");
+  }
+}
+

pom.xml

@@ -133,6 +133,12 @@
         <artifactId>junit</artifactId>
         <version>4.8.2</version>
       </dependency>
+      <dependency>
+        <groupId>com.google.truth</groupId>
+        <artifactId>truth</artifactId>
+        <version>0.40</version>
+        <scope>test</scope>
+      </dependency>
       <dependency>
         <groupId>com.google.appengine</groupId>
         <artifactId>appengine-api-1.0-sdk</artifactId>