From 6bbfcc3fec703438690f308f3a706f58c87380e1 Mon Sep 17 00:00:00 2001
From: Jorge Canizales <jcanizales@google.com>
Date: Wed, 17 Jun 2015 14:10:52 -0700
Subject: [PATCH] Disallow started request writers on GRPCCall init

---
 src/objective-c/GRPCClient/GRPCCall.m | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/objective-c/GRPCClient/GRPCCall.m b/src/objective-c/GRPCClient/GRPCCall.m
index 279ef935d50..687932c9381 100644
--- a/src/objective-c/GRPCClient/GRPCCall.m
+++ b/src/objective-c/GRPCClient/GRPCCall.m
@@ -100,7 +100,9 @@ NSString * const kGRPCStatusMetadataKey = @"io.grpc.StatusMetadataKey";
   if (!host || !method) {
     [NSException raise:NSInvalidArgumentException format:@"Neither host nor method can be nil."];
   }
-  // TODO(jcanizales): Throw if the requestWriter was already started.
+  if (requestWriter.state != GRXWriterStateNotStarted) {
+    [NSException raise:NSInvalidArgumentException format:@"The requests writer can't be already started."];
+  }
   if ((self = [super init])) {
     static dispatch_once_t initialization;
     dispatch_once(&initialization, ^{