Tag Archives: Swift

Leave Swift Error Propagation Enabled

A harmless Database update

I was debugging a Swift Mac app that I’m developing that uses Realm for a database.  The version of RealmSwift I was currently using was 2.10.0 as specified in my Podfile.

I opened Realm Browser to inspect a record in my database.   Having been recently updated to version 3.0.1, it alerted me that my database was using an older file format and offered to upgrade it.   I accepted without thinking much of it.

An unexpected error

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Error reporting for complex unit tests

System level unit testing

I was recently putting together the structure for some system level unit tests of a Swift project.   The structure extended beyond a single file for these tests.   I currently have:

  • SystemTests – Base class for a suite of system level unit tests.
  • BasicSystemTests – Class for my first group of unit tests.  Derives from SystemTests.
  • Various utility classes, each specific to a major section of the project.

Here is an example chain of calls coming from a test case:


   func testModified () {
        // Test modification to Project
        createProject(name: "Test Project", bundleId: "TestBundleId", appDelegate: "TestAppDelegate", fsConfig: "TestFsConfig", description: "Test Project Description")


   func createProject(name: String, bundleId: String, appDelegate: String?, fsConfig: String?, description: String?) -> String? {
        // Is Add New button enabled?
        project.verifyAddNewButton(enabled: false)


    func verifyAddNewButton(enabled: Bool) {
        XCTAssertEqual(addNewButton.isEnabled, enabled, "Add New button enabled = \(enabled)")

The problem – what is the path?

My test case has a bug.  When I run the test case, I see the following in Issue Navigator and the source code editor:

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Debugging in LLDB with command regex


Add the following to ~/.lldbinit and examine Swift objects in LLDB with “mp myobject” for both iOS and macOS, including those in NSView for macOS.

command regex mp 's/(.+)/expr Swift.print(%1)/'

Read on for more info

Goodbye po

I wanted to share a quick tip I discovered that allowed me to more easily examine objects.

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Swift framework development for binary distribution with CocoaPods

Swift Framework with Objective-C

Having previously developed some Objective-C based frameworks, I set out to explore doing the same with Swift and be able to deliver the framework as a Pod.

Creating a a Swift Framework is pretty straightforward and there are some great references on the subject.  One that I found very helpful was Creating and Distributing iOS Frameworks

I wanted to include some Objective-C based CocoaPods in my Swift Framework and quickly ran into an issue – you can’t use bridging headers with framework targets.

I did find a workaround which was interesting.  An answer in the thread Importing CommonCrypto in a Swift framework showed how to create a module that could be imported into Swift using an Aggregate target.  Using this answer as a guide, I was able to create a module for AFNetworking using the run script:

mkdir -p "${BUILT_PRODUCTS_DIR}/AFNetworkingModuleMap"
cat <<EOF > "${BUILT_PRODUCTS_DIR}/AFNetworkingModuleMap/module.modulemap"
module AFNetworking [system] {
header "${PODS_ROOT}/Headers/Public/AFNetworking/AFNetworking.h"
export *

This was interesting, but not the right approach.

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Exporting a video in iOS to reduce size and ensure maximum client compatibility

Movies that lay on their side

Have you ever taken a Portrait oriented movie with your iPhone or iPad and sent it to your friends who were using Windows?   I can understand their frustration when the video I so carefully recorded causes them to bend their neck to the side:


So what’s going on here?  The problem is that the .MOV file that I send them has a 90 degree rotation set as the preferred transform.   Some Windows clients (such as Windows Media Player, VLC media player, etc) do not take this transform into consideration when presenting the video.

The VideoExport Swift Project

I wanted to create a project that would allow me to address the issue with rotations and other compatibility concerns.

I published my results to scottcarter/VideoExport on Github.

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