Fix nullability incompatibility

src/compiler/objective_c_generator.cc

@@ -355,7 +355,7 @@ void PrintMethodImplementations(Printer* printer,
                   "@implementation $service_class$\n\n"
                   "// Designated initializer\n"
                   "- (instancetype)initWithHost:(NSString *)host "
-                  "callOptions:(GRPCCallOptions *_Nullable)callOptions{\n"
+                  "callOptions:(GRPCCallOptions *_Nullable)callOptions {\n"
                   "  self = [super initWithHost:host\n"
                   "                 packageName:@\"$package$\"\n"
                   "                 serviceName:@\"$service_name$\"\n"
@@ -363,10 +363,9 @@ void PrintMethodImplementations(Printer* printer,
                   "  return self;\n"
                   "}\n\n"
                   "- (instancetype)initWithHost:(NSString *)host {\n"
-                  "  return [self initWithHost:host\n"
+                  "  return [super initWithHost:host\n"
-                  "                packageName:@\"$package$\"\n"
+                  "                 packageName:@\"$package$\"\n"
-                  "                serviceName:@\"$service_name$\"\n"
+                  "                 serviceName:@\"$service_name$\"];\n"
-                  "                callOptions:nil];\n"
                   "}\n\n");
 
     printer.Print(
@@ -381,7 +380,7 @@ void PrintMethodImplementations(Printer* printer,
     printer.Print(
         "#pragma mark - Class Methods\n\n"
         "+ (instancetype)serviceWithHost:(NSString *)host {\n"
-        "  return [self serviceWithHost:host callOptions:nil];\n"
+        "  return [[self alloc] initWithHost:host];\n"
         "}\n\n"
         "+ (instancetype)serviceWithHost:(NSString *)host "
         "callOptions:(GRPCCallOptions *_Nullable)callOptions {\n"

src/objective-c/ProtoRPC/ProtoRPC.h

@@ -134,6 +134,9 @@ NS_ASSUME_NONNULL_BEGIN
 
 NS_ASSUME_NONNULL_END
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnullability-completeness"
+
 __attribute__((deprecated("Please use GRPCProtoCall."))) @interface ProtoRPC
     : GRPCCall
 
@@ -160,3 +163,5 @@ __attribute__((deprecated("Please use GRPCProtoCall."))) @interface ProtoRPC
 #pragma clang diagnostic pop
 
                                @end
+
+#pragma clang diagnostic pop

src/objective-c/ProtoRPC/ProtoService.m

@@ -61,7 +61,15 @@
 - (instancetype)initWithHost:(NSString *)host
                  packageName:(NSString *)packageName
                  serviceName:(NSString *)serviceName {
-  return [self initWithHost:host packageName:packageName serviceName:serviceName callOptions:nil];
+  // Do not call designated initializer here due to nullability incompatibility. This method is from
+  // old API and does not assert on nullability of the parameters.
+  if ((self = [super init])) {
+    _host = [host copy];
+    _packageName = [packageName copy];
+    _serviceName = [serviceName copy];
+    _callOptions = nil;
+  }
+  return self;
 }
 
 - (GRPCProtoCall *)RPCToMethod:(NSString *)method