Skip to content

Instantly share code, notes, and snippets.

@piscisaureus
piscisaureus / pr.md
Created August 13, 2012 16:12
Checkout github pull requests locally

Locate the section for your github remote in the .git/config file. It looks like this:

[remote "origin"]
	fetch = +refs/heads/*:refs/remotes/origin/*
	url = git@github.com:joyent/node.git

Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this:

@steipete
steipete / gist:3933090
Created October 22, 2012 18:13
Simple main thread usage detector that I'm using in PSPDFKit to find performance problems early on.
// Smart little helper to find main thread hangs. Enable in appDidFinishLaunching.
// Only available with source code in DEBUG mode.
@interface PSPDFHangDetector : NSObject
+ (void)startHangDetector;
@end
@implementation PSPDFHangDetector
+ (void)startHangDetector {
#ifdef DEBUG
@cihancimen
cihancimen / string_contains_emoji
Created November 26, 2012 00:54
Check if an NSString contains an emoji character
- (BOOL)stringContainsEmoji:(NSString *)string {
__block BOOL returnValue = NO;
[string enumerateSubstringsInRange:NSMakeRange(0, [string length]) options:NSStringEnumerationByComposedCharacterSequences usingBlock:
^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
const unichar hs = [substring characterAtIndex:0];
// surrogate pair
if (0xd800 <= hs && hs <= 0xdbff) {
if (substring.length > 1) {
const unichar ls = [substring characterAtIndex:1];
@OliverLetterer
OliverLetterer / XCDUUID.m
Created January 26, 2013 17:05
With this gist, I, as a total assembly noob, am trying to understand the XCDUUID runtime hack (https://github.com/0xced/NSUUID/blob/1.0.1/NSUUID.m#L167-L221) to be able to use NSUUID on iOS < 6.0.
@implementation XCDUUID
+ (void) load
{
// query runtime if NSUUID class already exists, if so => done
if (objc_getClass("NSUUID"))
{
return;
}
@steipete
steipete / PSPDFUIKitMainThreadGuard.m
Last active October 30, 2025 15:53
This is a guard that tracks down UIKit access on threads other than main. This snippet is taken from the commercial iOS PDF framework http://pspdfkit.com, but relicensed under MIT. Works because a lot of calls internally call setNeedsDisplay or setNeedsLayout. Won't catch everything, but it's very lightweight and usually does the job.You might n…
// Taken from the commercial iOS PDF framework http://pspdfkit.com.
// Copyright (c) 2014 Peter Steinberger, PSPDFKit GmbH. All rights reserved.
// Licensed under MIT (http://opensource.org/licenses/MIT)
//
// You should only use this in debug builds. It doesn't use private API, but I wouldn't ship it.
// PLEASE DUPE rdar://27192338 (https://openradar.appspot.com/27192338) if you would like to see this in UIKit.
#import <objc/runtime.h>
#import <objc/message.h>
@steipete
steipete / UIKitLegacyDetector.m
Last active May 21, 2025 10:07
A simple way to detect at runtime if we're running in UIKit legacy mode or the new "flat" variant. Written for our PDF iOS SDK (http://pspdfkit.com), where the precompiled binary needs to detect at runtime in what variant it's running. Want more stuff like that? Follow me on Twitter: http://twitter.com/steipete
// Taken from http://PSPDFKit.com. This snippet is under public domain.
#define UIKitVersionNumber_iOS_7_0 0xB57
BOOL PSPDFIsUIKitFlatMode(void) {
static BOOL isUIKitFlatMode = NO;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
// We get the modern UIKit if system is running >= iOS 7 and we were linked with >= SDK 7.
if (kCFCoreFoundationVersionNumber >= kCFCoreFoundationVersionNumber_iOS_7_0) {
isUIKitFlatMode = (NSVersionOfLinkTimeLibrary("UIKit") >> 16) >= UIKitVersionNumber_iOS_7_0;
}
@lanephillips
lanephillips / CGRectAspectFit.m
Created October 7, 2013 21:05
Objective-C code to fit a CGRect inside or outside another CGRect while maintaining aspect ratio. The fitted rectangle is centered on the target rectangle.
CGFloat ScaleToAspectFitRectInRect(CGRect rfit, CGRect rtarget)
{
// first try to match width
CGFloat s = CGRectGetWidth(rtarget) / CGRectGetWidth(rfit);
// if we scale the height to make the widths equal, does it still fit?
if (CGRectGetHeight(rfit) * s <= CGRectGetHeight(rtarget)) {
return s;
}
// no, match height instead
return CGRectGetHeight(rtarget) / CGRectGetHeight(rfit);
@steipete
steipete / Macros.h
Last active October 30, 2025 15:55
Declare on your main init that all other init methods should call. It's a nice additional semantic warning. Works with Xcode 5.1 and above. Not tested with earlier variants, but should just be ignored. A reference to this macro shortly appeared in https://developer.apple.com/library/ios/releasenotes/ObjectiveC/ModernizationObjC/AdoptingModernObj…
#ifndef NS_DESIGNATED_INITIALIZER
#if __has_attribute(objc_designated_initializer)
#define NS_DESIGNATED_INITIALIZER __attribute((objc_designated_initializer))
#else
#define NS_DESIGNATED_INITIALIZER
#endif
#endif
@matthiasplappert
matthiasplappert / gist:9493050
Last active August 29, 2015 13:57
QuickLook Debugging for `UIView`
@interface UIView (MPAdditions)
@end
@implementation UIView (MPAdditions)
- (id)debugQuickLookObject {
if (self.bounds.size.width < 0.0f || self.bounds.size.height < 0.0f) {
return nil;
}
@andymatuschak
andymatuschak / MultiDirectionAdjudicatingScrollView.swift
Created January 26, 2015 19:31
Source for the Khan Academy app's unusual scrolling interactions
//
// MultiDirectionAdjudicatingScrollView.swift
// Khan Academy
//
// Created by Andy Matuschak on 12/16/14.
// Copyright (c) 2014 Khan Academy. All rights reserved.
//
import UIKit
import UIKit.UIGestureRecognizerSubclass