TwitterNetworkLayerTests/TNLResponseTest.m

//
//  TNLResponseTest.m
//  TwitterNetworkLayer
//
//  Created on 11/12/14.
//  Copyright © 2020 Twitter. All rights reserved.
//

#import "NSURLResponse+TNLAdditions.h"
#import "TNL_Project.h"
#import "TNLAttemptMetaData.h"
#import "TNLAttemptMetaData_Project.h"
#import "TNLAttemptMetrics_Project.h"
#import "TNLRequest.h"
#import "TNLResponse_Project.h"

@import XCTest;

// we need a leaway of at least 1 second since the timing is only to the 1 second granularity level
// that means rounding/truncation of the time could have the timing be up to a second off
#define ACCURACY_LEEWAY (1.15)

@interface TNLResponseEncodedRequestTest : NSObject <TNLRequest, NSSecureCoding>

/** The name of the source `TNLRequest` class that was encoded */
@property (nonatomic, readonly, copy, nullable) NSString *encodedSourceRequestClassName;
/** If the encoded source request has a body */
@property (nonatomic, readonly) BOOL encodedSourceRequestHadBody;

/** Unavailable */
- (instancetype)init NS_UNAVAILABLE;
/** Unavailable */
+ (instancetype)new NS_UNAVAILABLE;

@end

@implementation TNLResponseEncodedRequestTest
{
    NSURL *_URL;
    TNLHTTPMethod _HTTPMethodValue;
    NSDictionary<NSString *, NSString *> *_allHTTPHeaderFields;
}

+ (BOOL)supportsSecureCoding
{
    return YES;
}

- (instancetype)initWithCoder:(NSCoder *)coder
{
    if (self = [super init]) {
        _encodedSourceRequestHadBody = [coder decodeBoolForKey:@"hasBody"];
        _encodedSourceRequestClassName = [coder decodeObjectOfClass:[NSString class] forKey:@"sourceClass"];
        _URL = [coder decodeObjectOfClass:[NSURL class] forKey:@"URL"];
        _HTTPMethodValue = [coder decodeIntegerForKey:@"HTTPMethod"];
        _allHTTPHeaderFields = [coder decodeObjectOfClass:[NSDictionary class] forKey:@"HTTPHeaders"];
    }
    return self;
}

- (void)encodeWithCoder:(NSCoder *)coder
{
    [coder encodeBool:_encodedSourceRequestHadBody forKey:@"hasBody"];
    [coder encodeObject:_encodedSourceRequestClassName forKey:@"sourceClass"];
    [coder encodeObject:_URL forKey:@"URL"];
    [coder encodeInteger:_HTTPMethodValue forKey:@"HTTPMethod"];
    [coder encodeObject:_allHTTPHeaderFields forKey:@"HTTPHeaders"];
}

- (nullable NSURL *)URL
{
    return _URL;
}

- (TNLHTTPMethod)HTTPMethodValue
{
    return _HTTPMethodValue;
}

- (nullable NSDictionary<NSString *, NSString *> *)allHTTPHeaderFields
{
    return _allHTTPHeaderFields;
}

- (nullable NSData *)HTTPBody
{
    if (_encodedSourceRequestHadBody) {
        return [@"{\"body\":true}" dataUsingEncoding:NSUTF8StringEncoding];
    }
    return nil;
}

@end

@interface TNLResponseTest : XCTestCase

@end

@implementation TNLResponseTest

- (void)testNSCoding
{
    NSURLRequest *finalRequest = [NSURLRequest requestWithURL:[NSURL URLWithString:@"http://m.dummy.com"]];
    NSHTTPURLResponse *urlResponse = [[NSHTTPURLResponse alloc] initWithURL:finalRequest.URL statusCode:200 HTTPVersion:@"HTTP/1.1" headerFields:@{ @"Header1" : @"Value1" }];
    id<TNLTemporaryFile> tempFile = nil;
    TNLResponseSource source = TNLResponseSourceNetworkRequest;
    NSData *data = [@"{ success: true }" dataUsingEncoding:NSUTF8StringEncoding];

    NSMutableURLRequest *mRequest = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"http://www.dummy.co"]];
    [mRequest setValue:@"dummy" forHTTPHeaderField:@"X-Dummy"];
    mRequest.HTTPMethod = @"POST";
    mRequest.HTTPBody = [@"{\"dummy\":true}" dataUsingEncoding:NSUTF8StringEncoding];
    NSURLRequest *request = [mRequest copy];
    NSDictionary *userInfo = @{
                               NSUnderlyingErrorKey : [NSError errorWithDomain:NSURLErrorDomain code:NSURLErrorCannotConnectToHost userInfo:@{ NSDebugDescriptionErrorKey: @"Error with Host", @"tnl.debug" : @"not debuggable" }],
                               @"level" : @"top"
                               };
    NSError *error = TNLErrorCreateWithCodeAndUserInfo(TNLErrorCodeGlobalHostWasBlocked, userInfo);

    uint64_t enqueueTime, firstAttemptStartTime, currentAttemptStartTime, currentAttemptEndTime, completeTime = 0;
    NSDate *enqueueDate, *firstAttemptStartDate, *currentAttemptStartDate, *currentAttemptEndDate, *completeDate;
    TNLAttemptMetaData *metaData = [[TNLAttemptMetaData alloc] init];
    metaData.HTTPVersion = @"1.1";

    NSData *archive = nil;
    TNLResponse *decodedResponse = nil;

    // enqueue
    enqueueDate = [NSDate date];
    enqueueTime = (UInt64)(NSEC_PER_SEC * CFAbsoluteTimeGetCurrent());

    // start, 1 sec later
    firstAttemptStartDate = currentAttemptStartDate = [enqueueDate dateByAddingTimeInterval:1];
    firstAttemptStartTime = currentAttemptStartTime = enqueueTime + (NSEC_PER_SEC * 1ULL);

    // end, 1 second later
    currentAttemptEndDate = [firstAttemptStartDate dateByAddingTimeInterval:1];
    currentAttemptEndTime = currentAttemptStartTime + (NSEC_PER_SEC * 1ULL);

    // complete, 1 ms later
    completeDate = [currentAttemptEndDate dateByAddingTimeInterval:1.0 / 1000.0];
    completeTime = currentAttemptEndTime + NSEC_PER_MSEC;

    TNLResponseInfo *info = [[TNLResponseInfo alloc] initWithFinalURLRequest:finalRequest
                                                                 URLResponse:urlResponse
                                                                      source:source
                                                                        data:data
                                                          temporarySavedFile:tempFile];
    TNLResponseMetrics *metrics = [[TNLResponseMetrics alloc] initWithEnqueueDate:enqueueDate
                                                                      enqueueTime:enqueueTime
                                                                     completeDate:completeDate
                                                                     completeTime:completeTime
                                                                   attemptMetrics:nil];
    [metrics addInitialStartWithDate:firstAttemptStartDate
                            machTime:firstAttemptStartTime
                             request:finalRequest];
    [metrics addMetaData:metaData taskMetrics:nil];
    [metrics addEndDate:currentAttemptEndDate
               machTime:currentAttemptEndTime
               response:info.URLResponse
         operationError:error];
    TNLResponse *response = [TNLResponse responseWithRequest:request
                                              operationError:error
                                                        info:info
                                                     metrics:metrics];

    XCTAssertEqualWithAccuracy(response.metrics.totalDuration, 2.001, 0.0005);
    XCTAssertEqualWithAccuracy(response.metrics.queuedDuration, 1.0, 0.0005);
    XCTAssertEqualWithAccuracy(response.metrics.allAttemptsDuration, 1.0, 0.0005);
    XCTAssertEqualWithAccuracy(response.metrics.currentAttemptDuration, 1.0, 0.0005);

    if (tnl_available_ios_11) {
        error = nil;
        archive = [NSKeyedArchiver archivedDataWithRootObject:response requiringSecureCoding:YES error:&error];
#if !TARGET_OS_MACCATALYST
    } else {
        archive = [NSKeyedArchiver archivedDataWithRootObject:response];
#endif
    }

    XCTAssertNotEqual(0UL, archive.length);

    if (tnl_available_ios_11) {
        error = nil;
        decodedResponse = [NSKeyedUnarchiver unarchivedObjectOfClass:[TNLResponse class] fromData:archive error:&error];
#if !TARGET_OS_MACCATALYST
    } else {
        decodedResponse = [NSKeyedUnarchiver unarchiveObjectWithData:archive];
#endif
    }

    XCTAssertTrue([decodedResponse isKindOfClass:[TNLResponse class]]);
    if (![decodedResponse isKindOfClass:[TNLResponse class]]) {
        return;
    }

    // metrics
    XCTAssertEqualWithAccuracy(response.metrics.totalDuration, decodedResponse.metrics.totalDuration, 0.0005);
    XCTAssertEqualWithAccuracy(response.metrics.queuedDuration, decodedResponse.metrics.queuedDuration, 0.0005);
    XCTAssertEqualWithAccuracy(response.metrics.allAttemptsDuration, decodedResponse.metrics.allAttemptsDuration, 0.0005);
    XCTAssertEqualWithAccuracy(response.metrics.currentAttemptDuration, decodedResponse.metrics.currentAttemptDuration, 0.0005);
    XCTAssertEqualObjects([response.metrics.attemptMetrics.lastObject metaData], [decodedResponse.metrics.attemptMetrics.lastObject metaData]);
    XCTAssertEqual(response.metrics.attemptCount, decodedResponse.metrics.attemptCount);
    XCTAssertEqualObjects(response.metrics, decodedResponse.metrics);
    XCTAssertEqual([response.metrics.attemptMetrics.firstObject attemptType], [decodedResponse.metrics.attemptMetrics.firstObject attemptType]);

    // info
    XCTAssertEqualObjects(response.info.finalURLRequest, decodedResponse.info.finalURLRequest);
    XCTAssertTrue([response.info.URLResponse tnl_isEqualToResponse:decodedResponse.info.URLResponse]);
    XCTAssertEqualObjects(response.info.data, decodedResponse.info.data);
    XCTAssertTrue((response.info.temporarySavedFile == nil) == (decodedResponse.info.temporarySavedFile == nil));
    XCTAssertEqualObjects(response.info, decodedResponse.info);

    // base
    XCTAssertEqualObjects(TNLErrorToSecureCodingError(response.operationError), decodedResponse.operationError);
    XCTAssertTrue(TNLRequestEqualToRequest(response.originalRequest, decodedResponse.originalRequest, YES /*quickBodyCheck*/), @"%@ must be equal to %@", response.originalRequest, decodedResponse.originalRequest);
    XCTAssertEqualObjects(response, decodedResponse);

    /// Try decoding with a mapping
    TNLResponseEncodedRequest *encodedRequest = [[TNLResponseEncodedRequest alloc] initWithSourceRequest:request];
    response = [TNLResponse responseWithRequest:encodedRequest
                                 operationError:error
                                           info:info
                                        metrics:metrics];

    [NSKeyedUnarchiver setClass:[TNLResponseEncodedRequestTest class] forClassName:@"TNLResponseEncodedRequest"];
    tnl_defer(^{
        [NSKeyedUnarchiver setClass:Nil forClassName:@"TNLResponseEncodedRequest"];
    });

    if (tnl_available_ios_11) {
        error = nil;
        archive = [NSKeyedArchiver archivedDataWithRootObject:response requiringSecureCoding:YES error:&error];
#if !TARGET_OS_MACCATALYST
    } else {
        archive = [NSKeyedArchiver archivedDataWithRootObject:response];
#endif
    }

    XCTAssertNotEqual(0UL, archive.length);

    if (tnl_available_ios_11) {
        error = nil;
        decodedResponse = [NSKeyedUnarchiver unarchivedObjectOfClass:[TNLResponse class] fromData:archive error:&error];
#if !TARGET_OS_MACCATALYST
    } else {
        decodedResponse = [NSKeyedUnarchiver unarchiveObjectWithData:archive];
#endif
    }

    XCTAssertTrue([decodedResponse isKindOfClass:[TNLResponse class]]);
    if (![decodedResponse isKindOfClass:[TNLResponse class]]) {
        return;
    }

    XCTAssertTrue(TNLRequestEqualToRequest(response.originalRequest, decodedResponse.originalRequest, YES /*quickBodyCheck*/));
}

- (void)testRetryAfterMethods
{
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    NSLocale *enUSPOSIXLocale = [[NSLocale alloc] initWithLocaleIdentifier:@"en_US_POSIX"];
    dateFormatter.locale = enUSPOSIXLocale;
    dateFormatter.timeZone = [NSTimeZone timeZoneWithName:@"UTC"];

    TNLResponseInfo *info;
    NSString *value;
    NSDate *date;
    CFAbsoluteTime start, end;

    // Invalid

    start = CFAbsoluteTimeGetCurrent();
    value = nil;
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertFalse(info.hasRetryAfterHeader);
    XCTAssertNil(info.retryAfterRawValue);
    XCTAssertNil(info.retryAfterDate);
    XCTAssertEqual(NSTimeIntervalSince1970, info.retryAfterDelayFromNow);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"Dummy";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNil(info.retryAfterDate);
    XCTAssertEqual(NSTimeIntervalSince1970, info.retryAfterDelayFromNow);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"0.5";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNil(info.retryAfterDate);
    XCTAssertEqual(NSTimeIntervalSince1970, info.retryAfterDelayFromNow);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"-1";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNil(info.retryAfterDate);
    XCTAssertEqual(NSTimeIntervalSince1970, info.retryAfterDelayFromNow);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNil(info.retryAfterDate);
    XCTAssertEqual(NSTimeIntervalSince1970, info.retryAfterDelayFromNow);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"2147483648";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNil(info.retryAfterDate);
    XCTAssertEqual(NSTimeIntervalSince1970, info.retryAfterDelayFromNow);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"15000000000";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNil(info.retryAfterDate);
    XCTAssertEqual(NSTimeIntervalSince1970, info.retryAfterDelayFromNow);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    // Delay

    start = CFAbsoluteTimeGetCurrent();
    value = @"0";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 0.0, ACCURACY_LEEWAY);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"000";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 0.0, ACCURACY_LEEWAY);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"1";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 1.0, ACCURACY_LEEWAY);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"0000000000000000000001";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 1.0, ACCURACY_LEEWAY);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"64000";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 64000.0, ACCURACY_LEEWAY);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"2147483647";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 2147483647.0, ACCURACY_LEEWAY);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    start = CFAbsoluteTimeGetCurrent();
    value = @"0";
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    [[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:1.0]];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, -1.0, ACCURACY_LEEWAY);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 1.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    //                           Sun, 06 Nov 1994 08:49:37 GMT  ; RFC 822, updated by RFC 1123
    dateFormatter.dateFormat = @"EEE, dd MMM yyyy HH:mm:ss zzz";

    date = [NSDate dateWithTimeIntervalSinceNow:0.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 0.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    date = [NSDate dateWithTimeIntervalSinceNow:1.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 1.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    date = [NSDate dateWithTimeIntervalSinceNow:64000.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 64000.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    date = [NSDate dateWithTimeIntervalSinceNow:0.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    [[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:1.0]];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, -1.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 1.2) {
        NSLog(@"Slow execution!  %fs!", end - start - 1.0);
    }

    //                         Sunday, 06-Nov-94 08:49:37 GMT ; RFC 850, obsoleted by RFC 1036
    dateFormatter.dateFormat = @"EEEE, dd-MMM-yy HH:mm:ss zzz";

    date = [NSDate dateWithTimeIntervalSinceNow:0.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 0.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    date = [NSDate dateWithTimeIntervalSinceNow:1.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 1.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    date = [NSDate dateWithTimeIntervalSinceNow:64000.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 64000.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    date = [NSDate dateWithTimeIntervalSinceNow:0.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    [[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:1.0]];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, -1.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 1.2) {
        NSLog(@"Slow execution!  %fs!", end - start - 1.0);
    }

    //                           Sun Nov 6 08:49:37 1994       ; ANSI C's asctime() format
    dateFormatter.dateFormat = @"EEE MMM d HH:mm:ss yyyy";

    date = [NSDate dateWithTimeIntervalSinceNow:0.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 0.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    date = [NSDate dateWithTimeIntervalSinceNow:1.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 1.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    date = [NSDate dateWithTimeIntervalSinceNow:64000.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, 64000.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 0.2) {
        NSLog(@"Slow execution!  %fs!", end - start);
    }

    date = [NSDate dateWithTimeIntervalSinceNow:0.0];
    start = CFAbsoluteTimeGetCurrent();
    value = [dateFormatter stringFromDate:date];
    info = [self fakeResponseInfoWithRetryAfterHeaderValue:value];
    [[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:1.0]];
    XCTAssertTrue(info.hasRetryAfterHeader);
    XCTAssertEqualObjects(value, info.retryAfterRawValue);
    XCTAssertNotNil(info.retryAfterDate);
    XCTAssertEqualWithAccuracy(info.retryAfterDelayFromNow, -1.0, ACCURACY_LEEWAY, @"Value Date: %@, Parsed Date: %@", date, info.retryAfterDate);
    end = CFAbsoluteTimeGetCurrent();
    if (end - start > 1.2) {
        NSLog(@"Slow execution!  %fs!", end - start - 1.0);
    }
}

- (void)testValueForHeaderField
{
    NSString *const kExpectedValue = @"42";
    TNLResponseInfo *info = [self fakeResponseInfoWithRetryAfterHeaderValue:kExpectedValue];
    XCTAssertNotNil(info);
    XCTAssertEqualObjects([info valueForResponseHeaderField:@"Retry-After"], kExpectedValue);
    XCTAssertEqualObjects([info valueForResponseHeaderField:@"retry-after"], kExpectedValue);
    XCTAssertEqualObjects([info valueForResponseHeaderField:@"RETRY-AFTER"], kExpectedValue);
    XCTAssertNil([info valueForResponseHeaderField:@"retryafter"]);
    XCTAssertNil([info valueForResponseHeaderField:@""]);
    XCTAssertNil([info valueForResponseHeaderField:(NSString * __nonnull)nil]);
}

- (TNLResponseInfo *)fakeResponseInfoWithRetryAfterHeaderValue:(NSString *)retryAfterHeaderValue
{
    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"https://www.dummy.com"]];
    NSDictionary *dictionary = (retryAfterHeaderValue) ? @{ @"Retry-After" : retryAfterHeaderValue } : @{};
    NSHTTPURLResponse *response = [[NSHTTPURLResponse alloc] initWithURL:request.URL statusCode:TNLHTTPStatusCodeServiceUnavailable HTTPVersion:@"HTTP/1.1" headerFields:dictionary];
    TNLResponseInfo *info = [[TNLResponseInfo alloc] initWithFinalURLRequest:request URLResponse:response source:TNLResponseSourceNetworkRequest data:nil temporarySavedFile:nil];
    return info;
}

@end