Skip to main content

WTF Crash - ROFL

Thread : Crashed: WebThread
0  JavaScriptCore                 0x318728ae WTFCrash + 53
1  JavaScriptCore                 0x31872859 WTFPrintBacktrace + 128
2  JavaScriptCore                 0x31668dbb WTF::fastMalloc(unsigned long) + 1690
3  WebCore                        0x38b85d5d WTF::Vector::reserveCapacity(unsigned long) + 44
4  WebCore                        0x38b16623 WebCore::HTMLToken::appendToCharacter(unsigned short) + 114
5  WebCore                        0x38b0eb63 WebCore::HTMLTokenizer::nextToken(WebCore::SegmentedString&, WebCore::HTMLToken&) + 32630
6  WebCore                        0x38b06085 WebCore::HTMLDocumentParser::pumpTokenizer(WebCore::HTMLDocumentParser::SynchronousMode) + 164
7  WebCore                        0x38b75d0d WebCore::HTMLDocumentParser::append(WTF::PassRefPtr) + 292
8  WebCore                        0x38b75225 WebCore::DecodedDataDocumentParser::appendBytes(WebCore::DocumentWriter*, char const*, unsigned long) + 72
9  WebCore                        0x38b31bd1 WebCore::DocumentLoader::commitData(char const*, unsigned long) + 36
10 WebKit                         0x395242b7 -[WebHTMLRepresentation receivedData:withDataSource:] + 182
11 WebKit                         0x39524151 -[WebDataSource(WebInternal) _receivedData:] + 136
12 WebKit                         0x395240ad WebFrameLoaderClient::committedLoad(WebCore::DocumentLoader*, char const*, int) + 100
13 WebCore                        0x38b6cc45 WebCore::DocumentLoader::commitLoad(char const*, int) + 100
14 WebCore                        0x38b6cb9d WebCore::DocumentLoader::dataReceived(WebCore::CachedResource*, char const*, int) + 496
15 WebCore                        0x38b6b3b3 WebCore::DocumentLoader::continueAfterContentPolicy(WebCore::PolicyAction) + 762
16 WebCore                        0x38b6a9e3 WebCore::DocumentLoader::responseReceived(WebCore::CachedResource*, WebCore::ResourceResponse const&) + 654
17 WebCore                        0x38ddd78f WebCore::DocumentLoader::handleSubstituteDataLoadNow(WebCore::Timer*) + 318
18 WebCore                        0x38a933f7 WebCore::ThreadTimers::sharedTimerFiredInternal() + 134
19 WebCore                        0x38a93349 WebCore::timerFired(__CFRunLoopTimer*, void*) + 24
20 CoreFoundation                 0x306e31b7 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 14
21 CoreFoundation                 0x306e2dcf __CFRunLoopDoTimer + 782
22 CoreFoundation                 0x306e116b __CFRunLoopRun + 1210
23 CoreFoundation                 0x3064bf0f CFRunLoopRunSpecific + 522
24 CoreFoundation                 0x3064bcf3 CFRunLoopRunInMode + 106
25 WebCore                        0x38b2011b RunWebThread(void*) + 418
26 libsystem_pthread.dylib        0x3b828919 _pthread_body + 140
27 libsystem_pthread.dylib        0x3b82888b _pthread_start + 102


Most Favorite Posts

Pattern: Riblets vs. VIPER

Engineering the architecture behind Uber's new rider app

Not being held back by our extensive codebase and previous design choices gave us the freedom where we otherwise would have made compromises. The outcome is the sleek new app you see today, which implements a new mobile architecture across both iOS and Android. Read on to learn why we felt the need to create this new architecture pattern, called Riblets, and how it helps us reach our goals.

The platforms share:

Core architectureClass namesInheritance relationships between business logic unitsHow business logic is dividedPlugin points (names, existence, structure, etc.)Reactive programming chainsUnified platform components
Each Riblet is made up of one Router, Interactor, and Builder with its Component (hence the name), and optional Presenters and Views. The Router and Interactor handle the business logic, while the Presenter and View handle the view logic.


Implementing UI tests on iOS and Android using screenshot comparison tools

Have you ever thought when writing or maintaining UI tests, there must be a better way?

Take a look at screenshot tests provided by Google Firebase and Facebook:

A "snapshot test case" takes a configured UIView or CALayer and uses the renderInContext: method to get an image snapshot of its contents. It compares this snapshot to a "reference image" stored in your source code repository and fails the test if the two images don't match.

GitHub Facebook

Testing rendering for your Android app is hard. How do you prevent visual regressions in paddings and margins and colors from creeping in?
Iterating on UI code is hard. How do you quickly verify that your layout or view changes work correctly in all configurations?

screenshot-tests-for-android can solve these problems by providing a test framework that checks for visual differences across changes.

GitHub Facebook

Google Firebase Test Lab
Test Lab lets you run Espresso, …


WireMock is a flexible library for stubbing and mocking web services. Unlike general purpose mocking tools it works by creating an actual HTTP server that your code under test can connect to as it would a real web service.

It supports HTTP response stubbing, request verification, proxy/intercept, record/playback of stubs and fault injection, and can be used from within a unit test or deployed into a test environment.

Although it’s written in Java, there’s also a JSON API so you can use it with pretty much any language out there.

How to link to TestFlight App in iOS

There are two things you need to do. First, check to see if TestFlight is installed. Then create a new link to your app.

NSURL *customAppURL = [NSURL URLWithString:@"itms-beta://"];
if ([[UIApplication sharedApplication] canOpenURL:customAppURL]) {

    // TestFlight is installed

    // Special link that includes the app's Apple ID
    customAppURL = [NSURL URLWithString:@""]; 
    [[UIApplication sharedApplication] openURL:customAppURL];

This special URL will be opened directly in TestFlight.

Finally, if you are using iOS 9 (or later), you need to make an addition to your Info.plist to get the canOpenURL: method to work.

If your app is linked on or after iOS 9.0, you must declare the URL schemes you want to pass to this method. Do this by using the LSApplicationQueriesSchemes array in your Xcode project’s Info.plist file. For each URL scheme you want your app to use with this method, add it …

Stetho - A Chrome debug bridge for Android applications

Stetho is a sophisticated debug bridge for Android applications. When enabled, developers have access to the Chrome Developer Tools feature natively part of the Chrome desktop browser. Developers can also choose to enable the optional dumpapp tool which offers a powerful command-line interface to application internals.

Facebook Github

iOS 7 Blur Effect

Combining a strong colour with a blurred and translucent UINavigationBar in iOS 7.

// cheers to @stroughtonsmith for helping out with this one
UIColor *barColour = [UIColor colorWithRed:0.13f green:0.14f blue:0.15f alpha:1.00f];

UIView *colourView = [[UIView alloc] initWithFrame:CGRectMake(0.f, -20.f, 320.f, 64.f)];
colourView.opaque = NO;
colourView.alpha = .7f;
colourView.backgroundColor = barColour;

self.navigationBar.barTintColor = barColour;

[self.navigationBar.layer insertSublayer:colourView.layer atIndex:1];

GitHub Gist
See also

And also
myView.backgroundColor = [UIColor clearColor];
UIToolbar* bgToolbar = [[UIToolbar alloc] initWithFrame:myView.frame];
bgToolbar.barStyle = UIBarStyleDefault;
[myView.superview insertSubview:bgToolbar belowSubview:myView];

Why bother replicating the effect? Just draw a UIToolbar behind your view.

NSURLConnection with Accept-Encoding: gzip

For quite some time I ranted about not being able to use compressed network communcation out-of-the-box on the iPhone.

Despite being undocumented (or I just overlooked the hint), NSURLConnection does gzip decompression transparently!

That’s how to use it:

NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url
// set explicitly:
[request setValue:@"gzip" forHTTPHeaderField:@"Accept-Encoding"];