Write debugging helpers in Swift, combine them into powerful automation actions and run them as LLDB commands.

Let's say your app starts with a login form. How often do you fill out that form every day? Wouldn't it be nice to automate this? That's what LLDO is for.

Simply write some automation steps in a login.swift file

UIView.find(byAccessibilityID: "username_input")?.enterText("[email protected]")
UIView.find(byAccessibilityID: "password_input")?.enterText("awesome")
UISwitch.first()?.slide()
UIButton.first()?.tap()

and call the combined action from LLDB: (lldb) login.

1. Clone this repo
2. Open Example/LLDOSwiftHelper.xcodeproj
3. Run in the Simulator and wait to hit the breakpoint in AppDelegate.applicationDidBecomeActive.
4. Type the following commands in the LLDB prompt:

• command script import /path/to/LLDO (make the LLDO commands available in LLDB)
• lldo ../lldo_actions (load LLDO helpers and automation actions)
• login (call login action)

Of course, this works for all kinds of forms. Every workflow that brings your app into a desired state can be automated.

LLDO comes with a bunch of helper methods that make writing common automation actions very easy. If you're using the example app, you can try out a few of them:

// Poking around
po UIButton.first()
po UIView.current.all(UILabel.self)
po UIView.grep("Pass")
po UIView.find(byAccessibilityID: "username_input")
po UIView.current.tree().filter { $0.isHidden }

// Changing stuff
po UITextField.first()?.enterText("[email protected]")
po UISwitch.first()?.slide()
po UIButton.first()?.tap()

Check the documentation at lurado.github.io/LLDO for a complete list.

Helpers need to be extensions on existing classes (see (lldb) help load_swift_file for details). You can develop them like any other code in a Xcode project.

1. Run an application and pause it to start LLDB
2. Use the load_swift_file command to load the file
3. Call your helpers
4. Adjust the implementation
5. GOTO 1 (unfortunately loading a files twice in a LLDB session results in duplicate symbols)

⚠️ Do NOT add these files to your target! Helpers commonly contain code that you would never write in your production app. For debugging it's fine though.

LLDO actions are simple Swift files that contain a series of commands. Each file corresponds to an action of the same name, for example login.swift will be turned into a login action.

To load all actions in a folder, use the lldo or load_lldo_actions commands. By default these commands look for a lldo_actions folder, located next to the source file of the current breakpoint.

⚠️ Again, do NOT add these files to your target either! They are for debugging purpose only and should not be shipped with your app.

To not have to manually import the path to LLDO in every LLDB session, add the following line to your ~/.lldbinit:

command script import /path/to/LLDO

This always loads LLDO's LLDB commands and makes them available in every project.

You can use breakpoints to further automate the initialization. For example a symbolic breakpoint in @objc <module>.<AppDelegate>.init (e.g. @objc LLDO.AppDelegate.init) can be used to load LLDO.

This would also load all actions in a lldo_actions folder next to your Xcode project/workspace file.

Likewise breakpoints can be used to trigger actions. For instance a breakpoint in applicationDidBecomeActive can be used to call the login action in the example app.

It's important to check "Automatically continue" for those breakpoints. Otherwise you would have to press "Continue" every time the breakpoints are hit.

If your whole team uses LLDO, you can share common breakpoints by right clicking them and selecting "Share Breakpoint".

To be able to use the Swift helpers (and thus LLDO) in an Objective-C project on an iOS device, you need to bundle the necessary Swift runtime libraries:

1. Add a single Swift file
2. Do not create a bridging header
3. make sure you import UIKit

If you are curious why this is necessary, see (lldb) help load_swift_runtime for details.

This project has been heavily inspired by @kastiglione. You should check out his talk.

MIT - see LICENSE file.