Fix flakey grpc_streaming_transport_test

The Mock expectation needs to be set up before The transport is created,
or there's a slight chance of a race.

Also fix an error message mistake.

Fixed: b/350199274

Change-Id: I0871474057349da967b4463f4d7d4d3aa8a5deab

cc/transport/grpc_streaming_transport.cc

@@ -108,7 +108,7 @@ absl::StatusOr<ResponseWrapper> GrpcStreamingTransport::Send(
     absl::Status status = Close();
     if (status.ok()) {
       return absl::InternalError(
-          "failed to read request for unspecified reason. This is likely an "
+          "failed to write request for unspecified reason. This is likely an "
           "implementation bug.");
     } else {
       return absl::Status(status.code(), absl::StrCat("while writing request: ",
@@ -122,7 +122,7 @@ absl::StatusOr<ResponseWrapper> GrpcStreamingTransport::Send(
     absl::Status status = Close();
     if (status.ok()) {
       return absl::InternalError(
-          "failed to write request for unspecified reason. This is likely an "
+          "failed to read response for unspecified reason. This is likely an "
           "implementation bug.");
     } else {
       return absl::Status(status.code(), absl::StrCat("while reading request: ",

cc/transport/grpc_streaming_transport_test.cc

@@ -74,13 +74,12 @@ class GrpcStreamingTransportTest : public ::testing::Test {
 };
 
 TEST_F(GrpcStreamingTransportTest, InvokePropagatesSendError) {
-  GrpcStreamingTransport transport(stub_->Stream(&context_));
-
   EXPECT_CALL(mock_service_, Stream(_, _))
       .WillOnce([](grpc::ServerContext*, ServerStream* stream) {
         return grpc::Status(grpc::StatusCode::FAILED_PRECONDITION,
                             "fake error");
       });
+  GrpcStreamingTransport transport(stub_->Stream(&context_));
 
   EncryptedRequest request;
   absl::StatusOr<oak::crypto::v1::EncryptedResponse> response =
@@ -91,13 +90,12 @@ TEST_F(GrpcStreamingTransportTest, InvokePropagatesSendError) {
 }
 
 TEST_F(GrpcStreamingTransportTest, GetEndorsedEvidencePropagatesSendError) {
-  GrpcStreamingTransport transport(stub_->Stream(&context_));
-
   EXPECT_CALL(mock_service_, Stream(_, _))
       .WillOnce([](grpc::ServerContext*, ServerStream* stream) {
         return grpc::Status(grpc::StatusCode::FAILED_PRECONDITION,
                             "fake error");
       });
+  GrpcStreamingTransport transport(stub_->Stream(&context_));
 
   absl::StatusOr<EndorsedEvidence> response = transport.GetEndorsedEvidence();
   ASSERT_EQ(response.status(),
@@ -106,34 +104,31 @@ TEST_F(GrpcStreamingTransportTest, GetEndorsedEvidencePropagatesSendError) {
 }
 
 TEST_F(GrpcStreamingTransportTest, InvokePropagatesWeirdError) {
-  GrpcStreamingTransport transport(stub_->Stream(&context_));
-
   EXPECT_CALL(mock_service_, Stream(_, _))
       .WillOnce([](grpc::ServerContext*, ServerStream* stream) {
         return grpc::Status::OK;
       });
+  GrpcStreamingTransport transport(stub_->Stream(&context_));
 
   EncryptedRequest request;
   absl::StatusOr<oak::crypto::v1::EncryptedResponse> response =
       transport.Invoke(request);
 
   ASSERT_EQ(response.status().code(), absl::StatusCode::kInternal);
   EXPECT_THAT(response.status().message(),
-              testing::StartsWith("failed to read request"));
+              testing::StartsWith("failed to write request"));
 }
 
 TEST_F(GrpcStreamingTransportTest, GetEndorsedEvidencePropagatesWeirdError) {
-  ::grpc::ClientContext context;
-  GrpcStreamingTransport transport(stub_->Stream(&context));
-
   EXPECT_CALL(mock_service_, Stream(_, _))
       .WillOnce([](grpc::ServerContext*, ServerStream* stream) {
         return grpc::Status::OK;
       });
+  GrpcStreamingTransport transport(stub_->Stream(&context_));
 
   absl::StatusOr<EndorsedEvidence> response = transport.GetEndorsedEvidence();
 
   ASSERT_EQ(response.status().code(), absl::StatusCode::kInternal);
   EXPECT_THAT(response.status().message(),
-              testing::StartsWith("failed to read request"));
+              testing::StartsWith("failed to write request"));
 }