Fix percent encoding

NSURL+QueryDictionary/NSURL+QueryDictionary.m

@@ -8,6 +8,7 @@
 
 #import "NSURL+QueryDictionary.h"
 
+NSString *const uq_URLReservedChars     = @"=,!$&'()*+;@?\r\n\"<>#\t :/";
 static NSString *const kQuerySeparator  = @"&";
 static NSString *const kQueryDivider    = @"=";
 static NSString *const kQueryBegin      = @"?";
@@ -87,6 +88,8 @@ - (NSDictionary*) uq_URLQueryDictionary {
 
 @implementation NSDictionary (URLQuery)
 
+static inline NSString *uq_URLEscape(NSString *string);
+
 - (NSString *)uq_URLQueryString {
   return [self uq_URLQueryStringWithSortedKeys:NO];
 }
@@ -99,15 +102,24 @@ - (NSString*) uq_URLQueryStringWithSortedKeys:(BOOL)sortedKeys {
     NSString *value = nil;
     // beware of empty or null
     if (!(rawValue == [NSNull null] || ![rawValue description].length)) {
-      value = [[self[key] description] stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
+      value = uq_URLEscape([self[key] description]);
     }
     [queryString appendFormat:@"%@%@%@%@",
      queryString.length ? kQuerySeparator : @"",    // appending?
-     [key stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding],
+     uq_URLEscape(key),
      value ? kQueryDivider : @"",
      value ? value : @""];
   }
   return queryString.length ? queryString.copy : nil;
 }
 
+static inline NSString *uq_URLEscape(NSString *string) {
+    return ((__bridge_transfer NSString *)CFURLCreateStringByAddingPercentEscapes(
+        NULL,
+        (__bridge CFStringRef)string,
+        NULL,
+        (__bridge CFStringRef)uq_URLReservedChars,
+        kCFStringEncodingUTF8));
+}
+
 @end

UnitTests/UnitTests.m

@@ -11,6 +11,8 @@
 
 #define URL(STRING) ((NSURL*) [NSURL URLWithString: STRING])
 
+extern NSString *const uq_URLReservedChars;
+
 @interface UnitTests : XCTestCase
 @end
 
@@ -76,6 +78,22 @@ - (void) testShouldEncodeKeysAndValues {
                         @"Did not return correct keys/values");
 }
 
+- (void) testShouldEncodeValuesContainingReservedCharacters {
+    NSDictionary *dict = @{@"q": @"gin & tonic", @"other": uq_URLReservedChars};
+
+    XCTAssertEqualObjects([URL(@"http://www.foo.com") uq_URLByAppendingQueryDictionary:dict].absoluteString,
+    @"http://www.foo.com?q=gin%20%26%20tonic&other=%EF%BF%BC%3D%2C%21%24%26%27%28%29%2A%2B%3B%40%3F%0D%0A%22%3C%3E%23%09%20%3A%2F",
+    @"Did not return correct keys/values");
+}
+
+- (void) testShouldEncodeKeysContainingReservedCharacters {
+    NSDictionary *dict = @{ uq_URLReservedChars: @YES};
+
+    XCTAssertEqualObjects([URL(@"http://www.foo.com") uq_URLByAppendingQueryDictionary:dict].absoluteString,
+    @"http://www.foo.com?%EF%BF%BC%3D%2C%21%24%26%27%28%29%2A%2B%3B%40%3F%0D%0A%22%3C%3E%23%09%20%3A%2F=1",
+    @"Did not return correct keys/values");
+}
+
 - (void) testShouldDealWithEmptyDictionary {
   NSString *urlString = @"http://www.foo.com?aKey=aValue&another=val2#fragment";
   XCTAssertEqualObjects([URL(urlString) uq_URLByAppendingQueryDictionary:@{}].absoluteString,
@@ -87,7 +105,7 @@ - (void) testShouldHandleDictionaryValuesOtherThanStrings {
   NSDictionary *dict = @{@"number":@47, @"date":[NSDate distantPast]};
   XCTAssertEqualObjects([URL(@"http://www.foo.com/path")
                          uq_URLByAppendingQueryDictionary:dict].absoluteString,
-                        @"http://www.foo.com/path?number=47&date=0001-12-30%2000:00:00%20+0000",
+                        @"http://www.foo.com/path?number=47&date=0001-12-30%2000%3A00%3A00%20%2B0000",
                         @"Did not create correctly formatted URL");
 }