1 files changed, 67 insertions, 6 deletions
diff --git a/src/objective-c/tests/InteropTests.m b/src/objective-c/tests/InteropTests.m
index 494743d604..f04a7e6441 100644
--- a/src/objective-c/tests/InteropTests.m
+++ b/src/objective-c/tests/InteropTests.m
@@ -80,10 +80,6 @@
 
 #pragma mark Tests
 
-#ifdef GRPC_COMPILE_WITH_CRONET
-static cronet_engine *cronetEngine = NULL;
-#endif
-
 @implementation InteropTests {
   RMTTestService *_service;
 }
@@ -92,15 +88,22 @@ static cronet_engine *cronetEngine = NULL;
   return nil;
 }
 
+- (int32_t)encodingOverhead {
+  return 0;
+}
+
 - (void)setUp {
+  self.continueAfterFailure = NO;
+
+  [GRPCCall resetHostSettings];
+
   _service = self.class.host ? [RMTTestService serviceWithHost:self.class.host] : nil;
 #ifdef GRPC_COMPILE_WITH_CRONET
   if (cronetEngine == NULL) {
     // Cronet setup
     [Cronet setHttp2Enabled:YES];
     [Cronet start];
-    cronetEngine = [Cronet getGlobalEngine];
-    [GRPCCall useCronetWithEngine:cronetEngine];
+    [GRPCCall useCronetWithEngine:[Cronet getGlobalEngine]];
   }
 #endif
 }
@@ -146,6 +149,64 @@ static cronet_engine *cronetEngine = NULL;
   [self waitForExpectationsWithTimeout:16 handler:nil];
 }
 
+- (void)test4MBResponsesAreAccepted {
+  XCTAssertNotNil(self.class.host);
+  __weak XCTestExpectation *expectation = [self expectationWithDescription:@"MaxResponseSize"];
+
+  RMTSimpleRequest *request = [RMTSimpleRequest message];
+  const int32_t kPayloadSize = 4 * 1024 * 1024 - self.encodingOverhead; // 4MB - encoding overhead
+  request.responseSize = kPayloadSize;
+
+  [_service unaryCallWithRequest:request handler:^(RMTSimpleResponse *response, NSError *error) {
+    XCTAssertNil(error, @"Finished with unexpected error: %@", error);
+    XCTAssertEqual(response.payload.body.length, kPayloadSize);
+    [expectation fulfill];
+  }];
+
+  [self waitForExpectationsWithTimeout:16 handler:nil];
+}
+
+- (void)testResponsesOverMaxSizeFailWithActionableMessage {
+  XCTAssertNotNil(self.class.host);
+  __weak XCTestExpectation *expectation = [self expectationWithDescription:@"ResponseOverMaxSize"];
+
+  RMTSimpleRequest *request = [RMTSimpleRequest message];
+  const int32_t kPayloadSize = 4 * 1024 * 1024 - self.encodingOverhead + 1; // 1B over max size
+  request.responseSize = kPayloadSize;
+
+  [_service unaryCallWithRequest:request handler:^(RMTSimpleResponse *response, NSError *error) {
+    // TODO(jcanizales): Catch the error and rethrow it with an actionable message:
+    // - Use +[GRPCCall setResponseSizeLimit:forHost:] to set a higher limit.
+    // - If you're developing the server, consider using response streaming, or let clients filter
+    //   responses by setting a google.protobuf.FieldMask in the request:
+    //   https://github.com/google/protobuf/blob/master/src/google/protobuf/field_mask.proto
+    XCTAssertEqualObjects(error.localizedDescription, @"Max message size exceeded");
+    [expectation fulfill];
+  }];
+
+  [self waitForExpectationsWithTimeout:16 handler:nil];
+}
+
+- (void)testResponsesOver4MBAreAcceptedIfOptedIn {
+  XCTAssertNotNil(self.class.host);
+  __weak XCTestExpectation *expectation =
+      [self expectationWithDescription:@"HigherResponseSizeLimit"];
+
+  RMTSimpleRequest *request = [RMTSimpleRequest message];
+  const size_t kPayloadSize = 5 * 1024 * 1024; // 5MB
+  request.responseSize = kPayloadSize;
+
+  [GRPCCall setResponseSizeLimit:6 * 1024 * 1024 forHost:self.class.host];
+
+  [_service unaryCallWithRequest:request handler:^(RMTSimpleResponse *response, NSError *error) {
+    XCTAssertNil(error, @"Finished with unexpected error: %@", error);
+    XCTAssertEqual(response.payload.body.length, kPayloadSize);
+    [expectation fulfill];
+  }];
+
+  [self waitForExpectationsWithTimeout:16 handler:nil];
+}
+
 - (void)testClientStreamingRPC {
   XCTAssertNotNil(self.class.host);
   __weak XCTestExpectation *expectation = [self expectationWithDescription:@"ClientStreaming"];