test for https://github.com/OpenFeign/feign/pull/511

httpclient/pom.xml

@@ -34,6 +34,12 @@
       <scope>test</scope>
     </dependency>
 
+    <dependency>
+      <groupId>${project.groupId}</groupId>
+      <artifactId>feign-jaxrs</artifactId>
+      <scope>test</scope>
+    </dependency>
+
     <dependency>
       <groupId>com.squareup.okhttp3</groupId>
       <artifactId>mockwebserver</artifactId>

httpclient/src/test/java/feign/httpclient/ApacheHttpClientTest.java

@@ -18,6 +18,22 @@ package feign.httpclient;
 import feign.Feign;
 import feign.Feign.Builder;
 import feign.client.AbstractClientTest;
+import feign.jaxrs.JAXRSContract;
+import okhttp3.mockwebserver.MockResponse;
+import okhttp3.mockwebserver.RecordedRequest;
+import org.apache.http.client.HttpClient;
+import org.apache.http.impl.client.HttpClientBuilder;
+import org.junit.Test;
+
+import javax.ws.rs.GET;
+import javax.ws.rs.PUT;
+import javax.ws.rs.Path;
+import javax.ws.rs.QueryParam;
+
+import java.nio.charset.StandardCharsets;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
 
 /**
  * Tests client-specific behavior, such as ensuring Content-Length is sent when specified.
@@ -28,4 +44,37 @@ public class ApacheHttpClientTest extends AbstractClientTest {
     public Builder newBuilder() {
         return Feign.builder().client(new ApacheHttpClient());
     }
+
+    @Test
+    public void queryParamsAreRespectedWhenBodyIsEmpty() throws InterruptedException {
+        final HttpClient httpClient = HttpClientBuilder.create().build();
+        final JaxRsTestInterface testInterface = Feign.builder()
+                .contract(new JAXRSContract())
+                .client(new ApacheHttpClient(httpClient))
+                .target(JaxRsTestInterface.class, "http://localhost:" + server.getPort());
+
+        server.enqueue(new MockResponse().setBody("foo"));
+        server.enqueue(new MockResponse().setBody("foo"));
+
+        assertEquals("foo", testInterface.withBody("foo", "bar"));
+        final RecordedRequest request1 = server.takeRequest();
+        assertEquals("/withBody?foo=foo", request1.getPath());
+        assertEquals("bar", request1.getBody().readString(StandardCharsets.UTF_8));
+
+        assertEquals("foo", testInterface.withoutBody("foo"));
+        final RecordedRequest request2 = server.takeRequest();
+        assertEquals("/withoutBody?foo=foo", request2.getPath());
+        assertEquals("", request2.getBody().readString(StandardCharsets.UTF_8));
+    }
+
+    @Path("/")
+    public interface JaxRsTestInterface {
+        @PUT
+        @Path("/withBody")
+        public String withBody(@QueryParam("foo") String foo, String bar);
+
+        @PUT
+        @Path("/withoutBody")
+        public String withoutBody(@QueryParam("foo") String foo);
+    }
 }