interop-testing: Add special_status_message test

interop-testing/src/main/java/io/grpc/testing/integration/AbstractInteropTest.java

@@ -1532,6 +1532,27 @@ public abstract class AbstractInteropTest {
     assertStatsTrace("grpc.testing.TestService/FullDuplexCall", Status.Code.UNKNOWN);
   }
 
+  @Test
+  public void specialStatusMessage() throws Exception {
+    int errorCode = 2;
+    String errorMessage = "\t\ntest with whitespace\r\nand Unicode BMP ☺ and non-BMP 😈\t\n";
+    SimpleRequest simpleRequest = SimpleRequest.newBuilder()
+        .setResponseStatus(EchoStatus.newBuilder()
+            .setCode(errorCode)
+            .setMessage(errorMessage)
+            .build())
+        .build();
+
+    try {
+      blockingStub.unaryCall(simpleRequest);
+      fail();
+    } catch (StatusRuntimeException e) {
+      assertEquals(Status.UNKNOWN.getCode(), e.getStatus().getCode());
+      assertEquals(errorMessage, e.getStatus().getDescription());
+    }
+    assertStatsTrace("grpc.testing.TestService/UnaryCall", Status.Code.UNKNOWN);
+  }
+
   /** Sends an rpc to an unimplemented method within TestService. */
   @Test
   public void unimplementedMethod() {

interop-testing/src/main/java/io/grpc/testing/integration/TestCases.java

@@ -44,6 +44,7 @@ public enum TestCases {
   PER_RPC_CREDS("per rpc raw oauth2 access token auth"),
   CUSTOM_METADATA("unary and full duplex calls with metadata"),
   STATUS_CODE_AND_MESSAGE("request error code and message"),
+  SPECIAL_STATUS_MESSAGE("special characters in status message"),
   UNIMPLEMENTED_METHOD("call an unimplemented RPC method"),
   UNIMPLEMENTED_SERVICE("call an unimplemented RPC service"),
   CANCEL_AFTER_BEGIN("cancel stream after starting it"),

interop-testing/src/main/java/io/grpc/testing/integration/TestServiceClient.java

@@ -301,6 +301,10 @@ public class TestServiceClient {
         break;
       }
 
+      case SPECIAL_STATUS_MESSAGE:
+        tester.specialStatusMessage();
+        break;
+
       case UNIMPLEMENTED_METHOD: {
         tester.unimplementedMethod();
         break;

interop-testing/src/test/java/io/grpc/testing/integration/TestCasesTest.java

@@ -58,6 +58,7 @@ public class TestCasesTest {
       "per_rpc_creds",
       "custom_metadata",
       "status_code_and_message",
+      "special_status_message",
       "unimplemented_method",
       "unimplemented_service",
       "cancel_after_begin",