Fix debugger terminating immediately on iOS device debugging

[Copilot]

Fixes issue #114 where the debugger would terminate immediately after app launch when debugging iOS applications on physical devices, despite successful app installation and launch.

Problem

When using the "debugging-launch" task to debug iOS apps on physical devices, users experienced:

• App builds and installs successfully on device
• App launches correctly on device
• LLDB attaches to process but immediately shows "Process exited with code -1"
• Debug adapter exits, preventing any debugging

The same workflow worked perfectly on iOS Simulator, indicating a device-specific issue.

Root Cause

The issue was caused by the --console flag in the devicectl device process launch command. When this flag is used:

• devicectl attaches to the application console and waits for it to exit
• This causes the process to complete immediately after launching
• The debugger cannot attach to a process that has already exited

// Previous code - always used --console when available
const launchArgs = [
  "devicectl", "device", "process", "launch",
  isConsoleOptionSupported ? "--console" : null,  // This caused the issue
  "--json-output", jsonPath,
  "--terminate-existing",
  "--device", deviceId,
  bundleId
].filter(arg => arg !== null);

Solution

Modified the device launch logic to conditionally exclude the --console flag when launching in debug mode:

// New code - excludes --console in debug mode
const launchArgs = [
  "devicectl", "device", "process", "launch", 
  isConsoleOptionSupported && !option.debug ? "--console" : null,  // Fixed
  "--json-output", jsonPath,
  "--terminate-existing", 
  "--device", deviceId,
  bundleId
].filter(arg => arg !== null);

Changes Made

1. Added debug parameter: Added optional debug?: boolean to runOniOSDevice() function signature
2. Updated launch logic: Modified devicectl arguments to exclude --console when debug=true
3. Propagated debug flag: Updated all callers in provider.ts and commands.ts to pass the debug flag
4. Added comprehensive tests: Unit tests validate the console flag handling logic

Behavior After Fix

• Debug mode (debugging-launch task): Launches without --console, keeping process alive for debugger attachment
• Normal mode (launch task): Uses --console as before for console output capture
• Legacy Xcode (< v16): Maintains existing behavior since --console wasn't supported

Testing

Added unit tests covering:

• Console flag excluded when debug=true
• Console flag included when debug=false
• Backward compatibility with older Xcode versions
• Proper null argument filtering

All tests pass, TypeScript compilation successful, no linting issues.

Impact

• ✅ Fixes device debugging for iOS physical devices
• ✅ Preserves existing functionality for non-debug launches
• ✅ Maintains backward compatibility
• ✅ No breaking changes to public APIs

Closes #114

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[hyzyla]

Root Cause: The --console flag in devicectl device process launch causes the process to wait for the app to exit, which terminates the process immediately after launch. This prevents the debugger from attaching properly.

Find in the internet proof for that? @copilot

[jdaites]

Nice, are there plans for this to go in soon?

[hyzyla]

Nice, are there plans for this to go in soon?

I would like to move forward with this issue, but I'm not sure if Copilot hallucinated that solution or not

[jdaites]

Nice, are there plans for this to go in soon?

I would like to move forward with this issue, but I'm not sure if Copilot hallucinated that solution or not

Based on my analysis it looks like a legit solution. The --console flag cuases it to be dependent on the console, but separating them out allows the debugger to attach independently of the console. I didn't test this out, but in theory it should work.