Run in terminal fails with lldb-dap timeout

[timsneath]

Describe the bug
I'm working on an interactive command line app using Swift, and because it uses raw mode ANSI VT commands it needs to run in an external terminal rather the built-in VSCode terminal.

Adding the "runInTerminal": true entry to launch.json should enable this, but when running a debug session, it times out with an error message:

Timed out trying to get messages from the debug adaptor

To Reproduce
Steps to reproduce the behavior:

1. Create a console app
2. Set a breakpoint
3. Add the "runInTerminal": true entry to launch.json to set a debug configuration that uses the system terminal.
4. Start debug in VSCode
5. Error:

Command line in terminal shows as:

cd /Users/timsneath/src/kilo-swift ; /usr/bin/env /Applications/Xcode.app/Contents/Developer/usr/bin/lldb-dap --comm-file /var/folders/0_/gnsdt09d1j131m349083j4f40000gn/T/lldb-dap-run-in-terminal-comm-4afc92 --debugger-pid 76637 
--launch-target /Users/timsneath/src/kilo-swift/.build/debug/kilo 

Expected behavior
A clear and concise description of what you expected to happen.

Environment

• OS: macOS Sequoia 15.3
• Swift version (output of swift --version)

swift-driver version: 1.115.1 Apple Swift version 6.0.3 (swiftlang-6.0.3.1.10 clang-1600.0.30.1)
Target: arm64-apple-macosx15.0

• Visual Studio Code version: Version: 1.96.4 (Universal)
• vscode-swift version: 1.11.4

Additional context
Full launch.json:

{
    "configurations": [
        {
            "type": "swift-lldb",
            "request": "launch",
            "args": [],
            "runInTerminal": true,
            "cwd": "${workspaceFolder:kilo-swift}",
            "name": "Debug kilo",
            "program": "${workspaceFolder:kilo-swift}/.build/debug/kilo",
            "preLaunchTask": "swift: Build Debug kilo",
        },
        {
            "type": "swift-lldb",
            "request": "launch",
            "args": [],
            "cwd": "${workspaceFolder:kilo-swift}",
            "name": "Release kilo",
            "program": "${workspaceFolder:kilo-swift}/.build/release/kilo",
            "preLaunchTask": "swift: Build Release kilo"
        }
    ]
}

[plemarquand]

I had a go at reproducing this but I couldn't reproduce the issue. From VS Code, with your project open, could you run > Swift: Capture VS Code Diagnostic Bundle and choose Capture Minimal Diagnostics, and then zip/attach the resulting files here? This should give us a more complete picture of how you have your project configured and what your VS Code settings are.

[award999]

Is the swift.debugger.useDebugAdapterFromToolchain setting enabled?

[timsneath]

@award999 Yes, that was enabled. Turning it off got the breakpoint to hit.

We should support this, right?

[award999]

@timsneath are you still able to reproduce this when you add "runInTerminal": true to the launch configuration. A similar bug report came in and it had to do with swiftly. Do you recall if you were using swiftly back then? The other time I saw this was when my Xcode was in the middle of an update.