Merge pull request #2068 from bpoplauschi/improve_unit_tests

Fixed our tests and improved the code coverage

@@ -76,6 +76,7 @@
                     @"http://littlesvr.ca/apng/images/world-cup-2014-42.webp",
                     @"https://isparta.github.io/compare-webp/image/gif_webp/webp/2.webp",
                     @"https://nr-platform.s3.amazonaws.com/uploads/platform/published_extension/branding_icon/275/AmazonS3.png",
+                    @"http://via.placeholder.com/200x200.jpg",
                     nil];
 
         for (int i=0; i<100; i++) {

@@ -2,7 +2,7 @@ source 'https://github.com/CocoaPods/Specs.git'
 
 use_frameworks!
 
-xcodeproj 'SDWebImage Tests'
+project 'SDWebImage Tests'
 workspace '../SDWebImage'
 
 target 'Tests' do

@@ -26,7 +26,7 @@
     XCTestExpectation *expectation = [self expectationWithDescription:@"UIImageView setImageWithURL"];
     
     UIImageView *imageView = [[UIImageView alloc] init];
-    NSURL *originalImageURL = [NSURL URLWithString:@"https://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage050.jpg"];
+    NSURL *originalImageURL = [NSURL URLWithString:kTestJpegURL];
     [imageView sd_setImageWithURL:originalImageURL
                         completed:^(UIImage * _Nullable image, NSError * _Nullable error, SDImageCacheType cacheType, NSURL * _Nullable imageURL) {
                             expect(image).toNot.beNil();
@@ -42,7 +42,7 @@
     XCTestExpectation *expectation = [self expectationWithDescription:@"UIImageView setHighlightedImageWithURL"];
     
     UIImageView *imageView = [[UIImageView alloc] init];
-    NSURL *originalImageURL = [NSURL URLWithString:@"https://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage051.jpg"];
+    NSURL *originalImageURL = [NSURL URLWithString:kTestJpegURL];
     [imageView sd_setHighlightedImageWithURL:originalImageURL
                                    completed:^(UIImage * _Nullable image, NSError * _Nullable error, SDImageCacheType cacheType, NSURL * _Nullable imageURL) {
                                        expect(image).toNot.beNil();
@@ -58,7 +58,7 @@
     XCTestExpectation *expectation = [self expectationWithDescription:@"MKAnnotationView setImageWithURL"];
     
     MKAnnotationView *annotationView = [[MKAnnotationView alloc] init];
-    NSURL *originalImageURL = [NSURL URLWithString:@"https://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage052.jpg"];
+    NSURL *originalImageURL = [NSURL URLWithString:kTestJpegURL];
     [annotationView sd_setImageWithURL:originalImageURL
                              completed:^(UIImage * _Nullable image, NSError * _Nullable error, SDImageCacheType cacheType, NSURL * _Nullable imageURL) {
                                  expect(image).toNot.beNil();
@@ -74,7 +74,7 @@
     XCTestExpectation *expectation = [self expectationWithDescription:@"UIButton setImageWithURL normalState"];
     
     UIButton *button = [[UIButton alloc] init];
-    NSURL *originalImageURL = [NSURL URLWithString:@"https://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage053.jpg"];
+    NSURL *originalImageURL = [NSURL URLWithString:kTestJpegURL];
     [button sd_setImageWithURL:originalImageURL
                       forState:UIControlStateNormal
                      completed:^(UIImage * _Nullable image, NSError * _Nullable error, SDImageCacheType cacheType, NSURL * _Nullable imageURL) {
@@ -91,7 +91,7 @@
     XCTestExpectation *expectation = [self expectationWithDescription:@"UIButton setImageWithURL highlightedState"];
     
     UIButton *button = [[UIButton alloc] init];
-    NSURL *originalImageURL = [NSURL URLWithString:@"https://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage054.jpg"];
+    NSURL *originalImageURL = [NSURL URLWithString:kTestJpegURL];
     [button sd_setImageWithURL:originalImageURL
                       forState:UIControlStateHighlighted
                      completed:^(UIImage * _Nullable image, NSError * _Nullable error, SDImageCacheType cacheType, NSURL * _Nullable imageURL) {
@@ -108,7 +108,7 @@
     XCTestExpectation *expectation = [self expectationWithDescription:@"UIButton setBackgroundImageWithURL normalState"];
     
     UIButton *button = [[UIButton alloc] init];
-    NSURL *originalImageURL = [NSURL URLWithString:@"https://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage055.jpg"];
+    NSURL *originalImageURL = [NSURL URLWithString:kTestJpegURL];
     [button sd_setBackgroundImageWithURL:originalImageURL
                                 forState:UIControlStateNormal
                                completed:^(UIImage * _Nullable image, NSError * _Nullable error, SDImageCacheType cacheType, NSURL * _Nullable imageURL) {

@@ -14,24 +14,16 @@
 NSString *kImageTestKey = @"TestImageKey.jpg";
 
 @interface SDImageCacheTests : SDTestCase
-@property (strong, nonatomic) SDImageCache *sharedImageCache;
 @end
 
 @implementation SDImageCacheTests
 
-- (void)setUp {
-    [super setUp];
-    // Put setup code here. This method is called before the invocation of each test method in the class.
-    self.sharedImageCache = [SDImageCache sharedImageCache];
-    [self clearAllCaches];
-}
-
 - (void)test01SharedImageCache {
-    expect(self.sharedImageCache).toNot.beNil();
+    expect([SDImageCache sharedImageCache]).toNot.beNil();
 }
 
 - (void)test02Singleton{
-    expect(self.sharedImageCache).to.equal([SDImageCache sharedImageCache]);
+    expect([SDImageCache sharedImageCache]).to.equal([SDImageCache sharedImageCache]);
 }
 
 - (void)test03ImageCacheCanBeInstantiated {
@@ -42,16 +34,21 @@ NSString *kImageTestKey = @"TestImageKey.jpg";
 - (void)test04ClearDiskCache{
     XCTestExpectation *expectation = [self expectationWithDescription:@"Clear disk cache"];
     
-    [self.sharedImageCache storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
-    [self.sharedImageCache clearDiskOnCompletion:^{
-        [self.sharedImageCache diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
+    [[SDImageCache sharedImageCache] storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
+    [[SDImageCache sharedImageCache] clearDiskOnCompletion:^{
+        expect([[SDImageCache sharedImageCache] imageFromMemoryCacheForKey:kImageTestKey]).to.equal([self imageForTesting]);
+        [[SDImageCache sharedImageCache] diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
             if (!isInCache) {
-                [expectation fulfill];
+                [[SDImageCache sharedImageCache] calculateSizeWithCompletionBlock:^(NSUInteger fileCount, NSUInteger totalSize) {
+                    expect(fileCount).to.equal(0);
+                    [[SDImageCache sharedImageCache] removeImageForKey:kImageTestKey withCompletion:^{
+                        [expectation fulfill];
+                    }];
+                }];
             } else {
                 XCTFail(@"Image should not be in cache");
             }
         }];
-        expect([self.sharedImageCache imageFromMemoryCacheForKey:kImageTestKey]).to.equal([self imageForTesting]);
     }];
     [self waitForExpectationsWithCommonTimeout];
 }
@@ -59,15 +56,18 @@ NSString *kImageTestKey = @"TestImageKey.jpg";
 - (void)test05ClearMemoryCache{
     XCTestExpectation *expectation = [self expectationWithDescription:@"Clear memory cache"];
     
-    [self.sharedImageCache storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
-    [self.sharedImageCache clearMemory];
-    expect([self.sharedImageCache imageFromMemoryCacheForKey:kImageTestKey]).to.beNil;
-    [self.sharedImageCache diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
-        if (isInCache) {
-            [expectation fulfill];
-        } else {
-            XCTFail(@"Image should be in cache");
-        }
+    [[SDImageCache sharedImageCache] storeImage:[self imageForTesting] forKey:kImageTestKey completion:^{
+        [[SDImageCache sharedImageCache] clearMemory];
+        expect([[SDImageCache sharedImageCache] imageFromMemoryCacheForKey:kImageTestKey]).to.beNil;
+        [[SDImageCache sharedImageCache] diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
+            if (isInCache) {
+                [[SDImageCache sharedImageCache] removeImageForKey:kImageTestKey withCompletion:^{
+                    [expectation fulfill];
+                }];
+            } else {
+                XCTFail(@"Image should be in cache");
+            }
+        }];
     }];
     [self waitForExpectationsWithCommonTimeout];
 }
@@ -77,11 +77,13 @@ NSString *kImageTestKey = @"TestImageKey.jpg";
     XCTestExpectation *expectation = [self expectationWithDescription:@"storeImage forKey"];
     
     UIImage *image = [self imageForTesting];
-    [self.sharedImageCache storeImage:image forKey:kImageTestKey completion:nil];
-    expect([self.sharedImageCache imageFromMemoryCacheForKey:kImageTestKey]).to.equal(image);
-    [self.sharedImageCache diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
+    [[SDImageCache sharedImageCache] storeImage:image forKey:kImageTestKey completion:nil];
+    expect([[SDImageCache sharedImageCache] imageFromMemoryCacheForKey:kImageTestKey]).to.equal(image);
+    [[SDImageCache sharedImageCache] diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
         if (isInCache) {
-            [expectation fulfill];
+            [[SDImageCache sharedImageCache] removeImageForKey:kImageTestKey withCompletion:^{
+                [expectation fulfill];
+            }];
         } else {
             XCTFail(@"Image should be in cache");
         }
@@ -90,15 +92,17 @@ NSString *kImageTestKey = @"TestImageKey.jpg";
 }
 
 // Testing storeImage:forKey:toDisk:YES
-- (void)test07InsertionOfImageForcingDiskStorage{
+- (void)test07InsertionOfImageForcingDiskStorage {
     XCTestExpectation *expectation = [self expectationWithDescription:@"storeImage forKey toDisk=YES"];
     
     UIImage *image = [self imageForTesting];
-    [self.sharedImageCache storeImage:image forKey:kImageTestKey toDisk:YES completion:nil];
-    expect([self.sharedImageCache imageFromMemoryCacheForKey:kImageTestKey]).to.equal(image);
-    [self.sharedImageCache diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
+    [[SDImageCache sharedImageCache] storeImage:image forKey:kImageTestKey toDisk:YES completion:nil];
+    expect([[SDImageCache sharedImageCache] imageFromMemoryCacheForKey:kImageTestKey]).to.equal(image);
+    [[SDImageCache sharedImageCache] diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
         if (isInCache) {
-            [expectation fulfill];
+            [[SDImageCache sharedImageCache] removeImageForKey:kImageTestKey withCompletion:^{
+                [expectation fulfill];
+            }];
         } else {
             XCTFail(@"Image should be in cache");
         }
@@ -110,121 +114,129 @@ NSString *kImageTestKey = @"TestImageKey.jpg";
 - (void)test08InsertionOfImageOnlyInMemory {
     XCTestExpectation *expectation = [self expectationWithDescription:@"storeImage forKey toDisk=NO"];
     UIImage *image = [self imageForTesting];
-    [self.sharedImageCache storeImage:image forKey:kImageTestKey toDisk:NO completion:nil];
+    [[SDImageCache sharedImageCache] storeImage:image forKey:kImageTestKey toDisk:NO completion:nil];
     
-    expect([self.sharedImageCache imageFromMemoryCacheForKey:kImageTestKey]).to.equal([self imageForTesting]);
-    [self.sharedImageCache diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
+    expect([[SDImageCache sharedImageCache] imageFromMemoryCacheForKey:kImageTestKey]).to.equal([self imageForTesting]);
+    [[SDImageCache sharedImageCache] diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
         if (!isInCache) {
             [expectation fulfill];
         } else {
             XCTFail(@"Image should not be in cache");
         }
     }];
-    [self.sharedImageCache clearMemory];
-    expect([self.sharedImageCache imageFromMemoryCacheForKey:kImageTestKey]).to.beNil();
+    [[SDImageCache sharedImageCache] clearMemory];
+    expect([[SDImageCache sharedImageCache] imageFromMemoryCacheForKey:kImageTestKey]).to.beNil();
     [self waitForExpectationsWithCommonTimeout];
 }
 
-- (void)test09RetrieveImageThroughNSOperation{
-    //- (NSOperation *)queryCacheOperationForKey:(NSString *)key done:(SDWebImageQueryCompletedBlock)doneBlock;
+- (void)test09RetrieveImageThroughNSOperation {
+    XCTestExpectation *expectation = [self expectationWithDescription:@"queryCacheOperationForKey"];
     UIImage *imageForTesting = [self imageForTesting];
-    [self.sharedImageCache storeImage:imageForTesting forKey:kImageTestKey completion:nil];
-    NSOperation *operation = [self.sharedImageCache queryCacheOperationForKey:kImageTestKey done:^(UIImage *image, NSData *data, SDImageCacheType cacheType) {
+    [[SDImageCache sharedImageCache] storeImage:imageForTesting forKey:kImageTestKey completion:nil];
+    NSOperation *operation = [[SDImageCache sharedImageCache] queryCacheOperationForKey:kImageTestKey done:^(UIImage *image, NSData *data, SDImageCacheType cacheType) {
         expect(image).to.equal(imageForTesting);
+        [[SDImageCache sharedImageCache] removeImageForKey:kImageTestKey withCompletion:^{
+            [expectation fulfill];
+        }];
     }];
     expect(operation).toNot.beNil;
+    [operation start];
+    [self waitForExpectationsWithCommonTimeout];
 }
 
-- (void)test10RemoveImageForKeyWithCompletion{
-    [self.sharedImageCache storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
-    [self.sharedImageCache removeImageForKey:kImageTestKey withCompletion:^{
-        expect([self.sharedImageCache imageFromDiskCacheForKey:kImageTestKey]).to.beNil;
-        expect([self.sharedImageCache imageFromMemoryCacheForKey:kImageTestKey]).to.beNil;
+- (void)test10RemoveImageForKeyWithCompletion {
+    XCTestExpectation *expectation = [self expectationWithDescription:@"removeImageForKey"];
+    [[SDImageCache sharedImageCache] storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
+    [[SDImageCache sharedImageCache] removeImageForKey:kImageTestKey withCompletion:^{
+        expect([[SDImageCache sharedImageCache] imageFromDiskCacheForKey:kImageTestKey]).to.beNil;
+        expect([[SDImageCache sharedImageCache] imageFromMemoryCacheForKey:kImageTestKey]).to.beNil;
+        [expectation fulfill];
     }];
+    [self waitForExpectationsWithCommonTimeout];
 }
 
 - (void)test11RemoveImageforKeyNotFromDiskWithCompletion{
-    [self.sharedImageCache storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
-    [self.sharedImageCache removeImageForKey:kImageTestKey fromDisk:NO withCompletion:^{
-        expect([self.sharedImageCache imageFromDiskCacheForKey:kImageTestKey]).toNot.beNil;
-        expect([self.sharedImageCache imageFromMemoryCacheForKey:kImageTestKey]).to.beNil;
+    XCTestExpectation *expectation = [self expectationWithDescription:@"removeImageForKey fromDisk:NO"];
+    [[SDImageCache sharedImageCache] storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
+    [[SDImageCache sharedImageCache] removeImageForKey:kImageTestKey fromDisk:NO withCompletion:^{
+        expect([[SDImageCache sharedImageCache] imageFromDiskCacheForKey:kImageTestKey]).toNot.beNil;
+        expect([[SDImageCache sharedImageCache] imageFromMemoryCacheForKey:kImageTestKey]).to.beNil;
+        [expectation fulfill];
     }];
+    [self waitForExpectationsWithCommonTimeout];
 }
 
 - (void)test12RemoveImageforKeyFromDiskWithCompletion{
-    [self.sharedImageCache storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
-    [self.sharedImageCache removeImageForKey:kImageTestKey fromDisk:YES withCompletion:^{
-        expect([self.sharedImageCache imageFromDiskCacheForKey:kImageTestKey]).to.beNil;
-        expect([self.sharedImageCache imageFromMemoryCacheForKey:kImageTestKey]).to.beNil;
+    XCTestExpectation *expectation = [self expectationWithDescription:@"removeImageForKey fromDisk:YES"];
+    [[SDImageCache sharedImageCache] storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
+    [[SDImageCache sharedImageCache] removeImageForKey:kImageTestKey fromDisk:YES withCompletion:^{
+        expect([[SDImageCache sharedImageCache] imageFromDiskCacheForKey:kImageTestKey]).to.beNil;
+        expect([[SDImageCache sharedImageCache] imageFromMemoryCacheForKey:kImageTestKey]).to.beNil;
+        [expectation fulfill];
     }];
+    [self waitForExpectationsWithCommonTimeout];
 }
 
 - (void)test20InitialCacheSize{
-    expect([self.sharedImageCache getSize]).to.equal(0);
+    expect([[SDImageCache sharedImageCache] getSize]).to.equal(0);
 }
 
 - (void)test21InitialDiskCount{
-    [self.sharedImageCache storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
-    expect([self.sharedImageCache getDiskCount]).to.equal(1);
-}
-
-- (void)test22DiskCountAfterInsertion{
-    [self.sharedImageCache storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
-    expect([self.sharedImageCache getDiskCount]).to.equal(1);
+    XCTestExpectation *expectation = [self expectationWithDescription:@"getDiskCount"];
+    [[SDImageCache sharedImageCache] storeImage:[self imageForTesting] forKey:kImageTestKey completion:^{
+        expect([[SDImageCache sharedImageCache] getDiskCount]).to.equal(1);
+        [[SDImageCache sharedImageCache] removeImageForKey:kImageTestKey withCompletion:^{
+            [expectation fulfill];
+        }];
+    }];
+    [self waitForExpectationsWithCommonTimeout];
 }
 
 - (void)test31DefaultCachePathForAnyKey{
-    NSString *path = [self.sharedImageCache defaultCachePathForKey:kImageTestKey];
+    NSString *path = [[SDImageCache sharedImageCache] defaultCachePathForKey:kImageTestKey];
     expect(path).toNot.beNil;
 }
 
 - (void)test32CachePathForNonExistingKey{
-    NSString *path = [self.sharedImageCache cachePathForKey:kImageTestKey inPath:[self.sharedImageCache defaultCachePathForKey:kImageTestKey]];
+    NSString *path = [[SDImageCache sharedImageCache] cachePathForKey:kImageTestKey inPath:[[SDImageCache sharedImageCache] defaultCachePathForKey:kImageTestKey]];
     expect(path).to.beNil;
 }
 
 - (void)test33CachePathForExistingKey{
-    [self.sharedImageCache storeImage:[self imageForTesting] forKey:kImageTestKey completion:nil];
-    NSString *path = [self.sharedImageCache cachePathForKey:kImageTestKey inPath:[self.sharedImageCache defaultCachePathForKey:kImageTestKey]];
-    expect(path).notTo.beNil;
+    XCTestExpectation *expectation = [self expectationWithDescription:@"cachePathForKey inPath"];
+    [[SDImageCache sharedImageCache] storeImage:[self imageForTesting] forKey:kImageTestKey completion:^{
+        NSString *path = [[SDImageCache sharedImageCache] cachePathForKey:kImageTestKey inPath:[[SDImageCache sharedImageCache] defaultCachePathForKey:kImageTestKey]];
+        expect(path).notTo.beNil;
+        [[SDImageCache sharedImageCache] removeImageForKey:kImageTestKey withCompletion:^{
+            [expectation fulfill];
+        }];
+    }];
+    [self waitForExpectationsWithCommonTimeout];
 }
 
-// TODO -- Testing image data insertion
-
-// TODO -- this test is driving me crazy keeps failing for unknown reasons, sometimes the image data is not written to disk - disabling the test for now
-- (void)a40InsertionOfImageData {
+- (void)test40InsertionOfImageData {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Insertion of image data works"];
     
     UIImage *image = [UIImage imageWithContentsOfFile:[self testImagePath]];
     NSData *imageData = UIImageJPEGRepresentation(image, 1.0);
-    [self.sharedImageCache storeImageDataToDisk:imageData forKey:kImageTestKey];
+    [[SDImageCache sharedImageCache] storeImageDataToDisk:imageData forKey:kImageTestKey];
     
-    UIImage *storedImageFromMemory = [self.sharedImageCache imageFromMemoryCacheForKey:kImageTestKey];
+    UIImage *storedImageFromMemory = [[SDImageCache sharedImageCache] imageFromMemoryCacheForKey:kImageTestKey];
     expect(storedImageFromMemory).to.equal(nil);
     
-    NSString *cachePath = [self.sharedImageCache defaultCachePathForKey:kImageTestKey];
+    NSString *cachePath = [[SDImageCache sharedImageCache] defaultCachePathForKey:kImageTestKey];
     UIImage *cachedImage = [UIImage imageWithContentsOfFile:cachePath];
     NSData *storedImageData = UIImageJPEGRepresentation(cachedImage, 1.0);
     expect(storedImageData.length).to.beGreaterThan(0);
     expect(cachedImage.size).to.equal(image.size);
     // can't directly compare image and cachedImage because apparently there are some slight differences, even though the image is the same
     
-    __block int blocksCalled = 0;
-    
-    [self.sharedImageCache diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
+    [[SDImageCache sharedImageCache] diskImageExistsWithKey:kImageTestKey completion:^(BOOL isInCache) {
         expect(isInCache).to.equal(YES);
-        blocksCalled += 1;
-        if (blocksCalled == 2) {
-            [expectation fulfill];
-        }
-    }];
-    
-    [self.sharedImageCache calculateSizeWithCompletionBlock:^(NSUInteger fileCount, NSUInteger totalSize) {
-        expect(fileCount).to.beLessThan(100);
-        blocksCalled += 1;
-        if (blocksCalled == 2) {
+        
+        [[SDImageCache sharedImageCache] removeImageForKey:kImageTestKey withCompletion:^{
             [expectation fulfill];
-        }
+        }];
     }];
     
     [self waitForExpectationsWithCommonTimeout];
@@ -269,7 +281,10 @@ NSString *kImageTestKey = @"TestImageKey.jpg";
         }
         
         [[SDWebImageCodersManager sharedInstance] removeCoder:testDecoder];
-        [expectation fulfill];
+        
+        [[SDImageCache sharedImageCache] removeImageForKey:key withCompletion:^{
+            [expectation fulfill];
+        }];
     }];
     
     [self waitForExpectationsWithCommonTimeout];
@@ -277,14 +292,6 @@ NSString *kImageTestKey = @"TestImageKey.jpg";
 
 #pragma mark Helper methods
 
-- (void)clearAllCaches{
-    [self.sharedImageCache deleteOldFilesWithCompletionBlock:nil];
-    
-    // TODO: this is not ok, clearDiskOnCompletion will clear async, this means that when we execute the tests, the cache might not be cleared
-    [self.sharedImageCache clearDiskOnCompletion:nil];
-    [self.sharedImageCache clearMemory];
-}
-
 - (UIImage *)imageForTesting{
     static UIImage *reusableImage = nil;
     if (!reusableImage) {

@@ -13,11 +13,13 @@
 #import <XCTest/XCTest.h>
 #import <Expecta/Expecta.h>
 
-extern const int64_t kAsyncTestTimeout;
+FOUNDATION_EXPORT const int64_t kAsyncTestTimeout;
+FOUNDATION_EXPORT NSString * _Nonnull const kTestJpegURL;
+FOUNDATION_EXPORT NSString * _Nonnull const kTestPNGURL;
 
 @interface SDTestCase : XCTestCase
 
 - (void)waitForExpectationsWithCommonTimeout;
-- (void)waitForExpectationsWithCommonTimeoutUsingHandler:(XCWaitCompletionHandler)handler;
+- (void)waitForExpectationsWithCommonTimeoutUsingHandler:(nullable XCWaitCompletionHandler)handler;
 
 @end

@@ -10,6 +10,8 @@
 #import "SDTestCase.h"
 
 const int64_t kAsyncTestTimeout = 5;
+NSString *const kTestJpegURL = @"http://via.placeholder.com/50x50.jpg";
+NSString *const kTestPNGURL = @"http://via.placeholder.com/50x50.png";
 
 @implementation SDTestCase
 

@@ -11,6 +11,8 @@
 #import <SDWebImage/SDWebImageImageIOCoder.h>
 #import <SDWebImage/SDWebImageWebPCoder.h>
 #import <SDWebImage/UIImage+ForceDecode.h>
+#import <SDWebImage/SDWebImageGIFCoder.h>
+#import <SDWebImage/NSData+ImageContentType.h>
 
 @interface SDWebImageDecoderTests : SDTestCase
 
@@ -96,32 +98,63 @@
 
 - (void)test09ThatStaticWebPCoderWorks {
     NSURL *staticWebPURL = [[NSBundle bundleForClass:[self class]] URLForResource:@"TestImageStatic" withExtension:@"webp"];
-    NSData *staticWebPData = [NSData dataWithContentsOfURL:staticWebPURL];
-    UIImage *staticWebPImage = [[SDWebImageWebPCoder sharedCoder] decodedImageWithData:staticWebPData];
-    expect(staticWebPImage).toNot.beNil();
-    
-    NSData *outputData = [[SDWebImageWebPCoder sharedCoder] encodedDataWithImage:staticWebPImage format:SDImageFormatWebP];
-    expect(outputData).toNot.beNil();
+    [self verifyCoder:[SDWebImageWebPCoder sharedCoder]
+    withLocalImageURL:staticWebPURL
+      isAnimatedImage:NO];
 }
 
 - (void)test10ThatAnimatedWebPCoderWorks {
     NSURL *animatedWebPURL = [[NSBundle bundleForClass:[self class]] URLForResource:@"TestImageAnimated" withExtension:@"webp"];
-    NSData *animatedWebPData = [NSData dataWithContentsOfURL:animatedWebPURL];
-    UIImage *animatedWebPImage = [[SDWebImageWebPCoder sharedCoder] decodedImageWithData:animatedWebPData];
-    expect(animatedWebPImage).toNot.beNil();
-    expect(animatedWebPImage.images.count).to.beGreaterThan(0);
-    CGSize imageSize = animatedWebPImage.size;
-    CGFloat imageScale = animatedWebPImage.scale;
-    [animatedWebPImage.images enumerateObjectsUsingBlock:^(UIImage * _Nonnull image, NSUInteger idx, BOOL * _Nonnull stop) {
-        CGSize size = image.size;
-        CGFloat scale = image.scale;
-        expect(imageSize.width).to.equal(size.width);
-        expect(imageSize.height).to.equal(size.height);
-        expect(imageScale).to.equal(scale);
-    }];
+    [self verifyCoder:[SDWebImageWebPCoder sharedCoder]
+    withLocalImageURL:animatedWebPURL
+      isAnimatedImage:YES];
+}
+
+- (void)test20ThatOurGIFCoderWorksNotFLAnimatedImage {
+    NSURL *gifURL = [[NSBundle bundleForClass:[self class]] URLForResource:@"TestImage" withExtension:@"gif"];
+    [self verifyCoder:[SDWebImageGIFCoder sharedCoder]
+    withLocalImageURL:gifURL
+      isAnimatedImage:YES];
+}
+
+- (void)verifyCoder:(id<SDWebImageCoder>)coder
+  withLocalImageURL:(NSURL *)imageUrl
+    isAnimatedImage:(BOOL)isAnimated {
+    NSData *inputImageData = [NSData dataWithContentsOfURL:imageUrl];
+    expect(inputImageData).toNot.beNil();
+    SDImageFormat inputImageFormat = [NSData sd_imageFormatForImageData:inputImageData];
+    expect(inputImageFormat).toNot.equal(SDImageFormatUndefined);
+    
+    // 1 - check if we can decode - should be true
+    expect([coder canDecodeFromData:inputImageData]).to.beTruthy();
+    
+    // 2 - decode from NSData to UIImage and check it
+    UIImage *inputImage = [coder decodedImageWithData:inputImageData];
+    expect(inputImage).toNot.beNil();
+    
+    if (isAnimated) {
+        // 2a - check images count > 0 (only for animated images)
+        expect(inputImage.images.count).to.beGreaterThan(0);
+        
+        // 2b - check image size and scale for each frameImage (only for animated images)
+        CGSize imageSize = inputImage.size;
+        CGFloat imageScale = inputImage.scale;
+        [inputImage.images enumerateObjectsUsingBlock:^(UIImage * frameImage, NSUInteger idx, BOOL * stop) {
+            expect(imageSize).to.equal(frameImage.size);
+            expect(imageScale).to.equal(frameImage.scale);
+        }];
+    }
+    
+    // 3 - check if we can encode to the original format
+    expect([coder canEncodeToFormat:inputImageFormat]).to.beTruthy();
     
-    NSData *outputData = [[SDWebImageWebPCoder sharedCoder] encodedDataWithImage:animatedWebPImage format:SDImageFormatWebP];
-    expect(outputData).toNot.beNil();
+    // 4 - encode from UIImage to NSData using the inputImageFormat and check it
+    NSData *outputImageData = [coder encodedDataWithImage:inputImage format:inputImageFormat];
+    expect(outputImageData).toNot.beNil();
+    UIImage *outputImage = [coder decodedImageWithData:outputImageData];
+    expect(outputImage.size).to.equal(inputImage.size);
+    expect(outputImage.scale).to.equal(inputImage.scale);
+    expect(outputImage.images.count).to.equal(inputImage.images.count);
 }
 
 @end

@@ -80,7 +80,7 @@
 
 - (void)test04ThatASimpleDownloadWorks {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Simple download"];
-    NSURL *imageURL = [NSURL URLWithString:@"http://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage004.jpg"];
+    NSURL *imageURL = [NSURL URLWithString:kTestJpegURL];
     [[SDWebImageDownloader sharedDownloader] downloadImageWithURL:imageURL options:0 progress:nil completed:^(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, BOOL finished) {
         if (image && data && !error && finished) {
             [expectation fulfill];
@@ -145,7 +145,7 @@
 
 - (void)test09ThatProgressiveJPEGWorks {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Progressive JPEG download"];
-    NSURL *imageURL = [NSURL URLWithString:@"http://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage009.jpg"];
+    NSURL *imageURL = [NSURL URLWithString:kTestJpegURL];
     [[SDWebImageDownloader sharedDownloader] downloadImageWithURL:imageURL options:SDWebImageDownloaderProgressiveDownload progress:nil completed:^(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, BOOL finished) {
         if (image && data && !error && finished) {
             [expectation fulfill];
@@ -175,7 +175,7 @@
 - (void)test11ThatCancelWorks {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Cancel"];
     
-    NSURL *imageURL = [NSURL URLWithString:@"http://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage011.jpg"];
+    NSURL *imageURL = [NSURL URLWithString:kTestJpegURL];
     SDWebImageDownloadToken *token = [[SDWebImageDownloader sharedDownloader]
                                       downloadImageWithURL:imageURL options:0 progress:nil completed:^(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, BOOL finished) {
                                           XCTFail(@"Should not get here");
@@ -195,7 +195,7 @@
 
 - (void)test12ThatWeCanUseAnotherSessionForEachDownloadOperation {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Owned session"];
-    NSURL *imageURL = [NSURL URLWithString:@"http://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage012.jpg"];
+    NSURL *imageURL = [NSURL URLWithString:kTestJpegURL];
     
     NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:imageURL cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:15];
     request.HTTPShouldUsePipelining = YES;
@@ -221,7 +221,7 @@
 
 - (void)test13ThatDownloadCanContinueWhenTheAppEntersBackground {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Simple download"];
-    NSURL *imageURL = [NSURL URLWithString:@"http://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage013.jpg"];
+    NSURL *imageURL = [NSURL URLWithString:kTestJpegURL];
     [[SDWebImageDownloader sharedDownloader] downloadImageWithURL:imageURL options:SDWebImageDownloaderContinueInBackground progress:nil completed:^(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, BOOL finished) {
         if (image && data && !error && finished) {
             [expectation fulfill];
@@ -233,8 +233,8 @@
 }
 
 - (void)test14ThatPNGWorks {
-    XCTestExpectation *expectation = [self expectationWithDescription:@"WEBP"];
-    NSURL *imageURL = [NSURL URLWithString:@"https://nr-platform.s3.amazonaws.com/uploads/platform/published_extension/branding_icon/275/AmazonS3.png"];
+    XCTestExpectation *expectation = [self expectationWithDescription:@"PNG"];
+    NSURL *imageURL = [NSURL URLWithString:kTestPNGURL];
     [[SDWebImageDownloader sharedDownloader] downloadImageWithURL:imageURL options:0 progress:nil completed:^(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, BOOL finished) {
         if (image && data && !error && finished) {
             [expectation fulfill];
@@ -282,7 +282,7 @@
 - (void)test20ThatDownloadingSameURLTwiceAndCancellingFirstWorks {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Correct image downloads"];
     
-    NSURL *imageURL = [NSURL URLWithString:@"http://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage020.jpg"];
+    NSURL *imageURL = [NSURL URLWithString:kTestJpegURL];
     
     SDWebImageDownloadToken *token1 = [[SDWebImageDownloader sharedDownloader]
                                        downloadImageWithURL:imageURL
@@ -320,7 +320,7 @@
 - (void)test21ThatCancelingDownloadThenRequestingAgainWorks {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Correct image downloads"];
     
-    NSURL *imageURL = [NSURL URLWithString:@"http://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage021.jpg"];
+    NSURL *imageURL = [NSURL URLWithString:kTestJpegURL];
     
     SDWebImageDownloadToken *token1 = [[SDWebImageDownloader sharedDownloader]
                                        downloadImageWithURL:imageURL

@@ -9,8 +9,6 @@
 #import "SDTestCase.h"
 #import <SDWebImage/SDWebImageManager.h>
 
-NSString *workingImageURL = @"http://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage001.jpg";
-
 @interface SDWebImageManagerTests : SDTestCase
 
 @end
@@ -25,7 +23,7 @@ NSString *workingImageURL = @"http://s3.amazonaws.com/fast-image-cache/demo-imag
 - (void)test02ThatDownloadInvokesCompletionBlockWithCorrectParamsAsync {
     __block XCTestExpectation *expectation = [self expectationWithDescription:@"Image download completes"];
 
-    NSURL *originalImageURL = [NSURL URLWithString:workingImageURL];
+    NSURL *originalImageURL = [NSURL URLWithString:kTestJpegURL];
     
     [[SDWebImageManager sharedManager] loadImageWithURL:originalImageURL
                                                 options:SDWebImageRefreshCached
@@ -65,7 +63,7 @@ NSString *workingImageURL = @"http://s3.amazonaws.com/fast-image-cache/demo-imag
 
 - (void)test04CachedImageExistsForURL {
     __block XCTestExpectation *expectation = [self expectationWithDescription:@"Image exists in cache"];
-    NSURL *imageURL = [NSURL URLWithString:workingImageURL];
+    NSURL *imageURL = [NSURL URLWithString:kTestJpegURL];
     [[SDWebImageManager sharedManager] cachedImageExistsForURL:imageURL completion:^(BOOL isInCache) {
         if (isInCache) {
             [expectation fulfill];
@@ -78,7 +76,7 @@ NSString *workingImageURL = @"http://s3.amazonaws.com/fast-image-cache/demo-imag
 
 - (void)test05DiskImageExistsForURL {
     __block XCTestExpectation *expectation = [self expectationWithDescription:@"Image exists in disk cache"];
-    NSURL *imageURL = [NSURL URLWithString:workingImageURL];
+    NSURL *imageURL = [NSURL URLWithString:kTestJpegURL];
     [[SDWebImageManager sharedManager] diskImageExistsForURL:imageURL completion:^(BOOL isInCache) {
         if (isInCache) {
             [expectation fulfill];
@@ -92,7 +90,9 @@ NSString *workingImageURL = @"http://s3.amazonaws.com/fast-image-cache/demo-imag
 - (void)test06CancellAll {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Cancel"];
     
-    NSURL *imageURL = [NSURL URLWithString:@"http://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage006.jpg"];
+    // need a bigger image here, that is why we don't use kTestJpegURL
+    // if the image is too small, it will get downloaded before we can cancel :)
+    NSURL *imageURL = [NSURL URLWithString:@"https://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage001.jpg"];
     [[SDWebImageManager sharedManager] loadImageWithURL:imageURL options:0 progress:nil completed:^(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, SDImageCacheType cacheType, BOOL finished, NSURL * _Nullable imageURL) {
         XCTFail(@"Should not get here");
     }];
@@ -110,7 +110,7 @@ NSString *workingImageURL = @"http://s3.amazonaws.com/fast-image-cache/demo-imag
 
 - (void)test07ThatLoadImageWithSDWebImageRefreshCachedWorks {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Image download twice with SDWebImageRefresh failed"];
-    NSURL *originalImageURL = [NSURL URLWithString:@"http://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage007.jpg"];
+    NSURL *originalImageURL = [NSURL URLWithString:kTestJpegURL];
     [[SDImageCache sharedImageCache] clearDiskOnCompletion:nil];
     
     [[SDWebImageManager sharedManager] loadImageWithURL:originalImageURL options:SDWebImageRefreshCached progress:nil completed:^(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, SDImageCacheType cacheType, BOOL finished, NSURL * _Nullable imageURL) {

@@ -24,13 +24,9 @@
 - (void)test02PrefetchMultipleImages {
     XCTestExpectation *expectation = [self expectationWithDescription:@"Correct prefetch of multiple images"];
     
-    NSMutableArray *imageURLs = [NSMutableArray array];
-    
-    for (int i=40; i<43; i++) {
-        NSString *imageURLString = [NSString stringWithFormat:@"https://s3.amazonaws.com/fast-image-cache/demo-images/FICDDemoImage%03d.jpg", i];
-        NSURL *imageURL = [NSURL URLWithString:imageURLString];
-        [imageURLs addObject:imageURL];
-    }
+    NSArray *imageURLs = @[@"http://via.placeholder.com/20x20.jpg",
+                           @"http://via.placeholder.com/30x30.jpg",
+                           @"http://via.placeholder.com/40x40.jpg"];
     
     __block int numberOfPrefetched = 0;