Changing multipartFormRequestWithMethod:... to black-list GET and HEAD rather than whitelist particular methods.

Enforcing non-nil, non-GET / HEAD method parameter requirement

AFNetworking/AFHTTPClient.h

@@ -254,15 +254,13 @@ typedef enum {
 /**
  Creates an `NSMutableURLRequest` object with the specified HTTP method and path, and constructs a `multipart/form-data` HTTP body, using the specified parameters and multipart form data block. See http://www.w3.org/TR/html4/interact/forms.html#h-17.13.4.2
  
- @param method The HTTP method for the request. Must be either `POST`, `PUT`, or `DELETE`.
+ @param method The HTTP method for the request. This parameter must not be `GET` or `HEAD`, or `nil`.
  @param path The path to be appended to the HTTP client's base URL and used as the request URL.
  @param parameters The parameters to be encoded and set in the request HTTP body.
  @param block A block that takes a single argument and appends data to the HTTP body. The block argument is an object adopting the `AFMultipartFormData` protocol. This can be used to upload files, encode HTTP body as JSON or XML, or specify multiple values for the same parameter, as one might for array values.
   
  @discussion Multipart form requests are automatically streamed, reading files directly from disk along with in-memory data in a single HTTP body. The resulting `NSMutableURLRequest` object has an `HTTPBodyStream` property, so refrain from setting `HTTPBodyStream` or `HTTPBody` on this request object, as it will clear out the multipart form body stream.
   
- @warning An exception will be raised if the specified method is not `POST`, `PUT` or `DELETE`.
- 
  @return An `NSMutableURLRequest` object
  */
 - (NSMutableURLRequest *)multipartFormRequestWithMethod:(NSString *)method

AFNetworking/AFHTTPClient.m

@@ -465,6 +465,9 @@ static void AFNetworkReachabilityReleaseCallback(const void *info) {}
                                              parameters:(NSDictionary *)parameters
                               constructingBodyWithBlock:(void (^)(id <AFMultipartFormData> formData))block
 {
+    NSCParameterAssert(method);
+    NSCParameterAssert(![method isEqualToString:@"GET"] && ![method isEqualToString:@"HEAD"]);
+    
     NSMutableURLRequest *request = [self requestWithMethod:method path:path parameters:nil];
 
     __block AFStreamingMultipartFormData *formData = [[AFStreamingMultipartFormData alloc] initWithURLRequest:request stringEncoding:self.stringEncoding];