debug: add replay mode to launch.json

[icholy]

Is your feature request related to a problem? Please describe.

There is no simple way to replay an rr execution trace.

• https://github.com/go-delve/delve/blob/master/Documentation/usage/dlv_replay.md
• https://github.com/rr-debugger/rr

Describe the solution you'd like
I'd like to specify the path to the trace file in launch.json.

{
    "name": "Replay Trace",
    "type": "go",
    "request": "launch",
    "mode": "replay",
    "traceFile": "/home/icholy/.local/share/rr/my.test-121",
    "program": "${workspaceFolder}"
}

Describe alternatives you've considered
I have tried starting dlv replay in headless mode and connecting remotely with vscode, but it doesn't register the breakpoints.

[hyangah]

There is a WIP PR #89 by @lggomez that adds the replay/coredump features to the old debug adapter. @lggomez @polinasok @suzmue is it possible to port the pr in delve dap?

[lggomez]

@hyangah I've been completely out of the loop since the handover of the extension and the development of the new adapter so I'd be grateful if I could get a quick rundown of the new dap; I can check if the old WIP is still applicable

[polinasok]

Discussion now happening at go-delve/delve#2367

[polinasok]

This feature is now available using the following in your launch.json

"request": "launch",
"mode": "replay",
"traceDirPath":"path/to/trace",

Thank you @lggomez for your contribution!

@icholy Please let us know if it is not working for you. Thank you.