Feature request: integrate debugging with `dotnet watch`

[Trottero]

Issue Description

Hi, im currently trying to set-up vscode in such a way that I can use both the debugger and dotnet watch run. When running dotnet watch run it spawns a new process eg weather.exe which the debugger can attach to. When you trigger a recompile however, dotnet watch run terminates the process weather.exe causing the debugger to also exit. This means that we have to restart the debugger every time the app is recompiled, which defeats the purpose of using dotnet watch in the first place.

I would suggest a configurable timeout for the debugger to give time to reattach to the previous instance once it gets detached.

I've attached launch.json, tasks.json and the log of my terminal after reloads, I've also included a repository down below.

Launch.json

{
  "version": "0.2.0",
  "configurations": [
    {
      "name": ".NET Core Attach",
      "type": "coreclr",
      "preLaunchTask": "watch",
      "request": "attach",
      "processName": "weather.exe"
    }
  ]
}

Tasks.json

{
  "version": "2.0.0",
  "tasks": [
    {
      "label": "watch",
      "command": "dotnet",
      "type": "process",
      "args": [
        "watch",
        "run",
        "${workspaceFolder}/weather.csproj",
        "/property:GenerateFullPaths=true",
        "/consoleloggerparameters:NoSummary"
      ],
      "problemMatcher": "$msCompile",
      "isBackground": true
    }
  ]
}

dotnet watch run log

> Executing task: C:\Program Files\dotnet\dotnet.exe watch run C:\Users\Niels\source\repos\dotnet-watch-attach/weather.csproj /property:GenerateFullPaths=true /consoleloggerparameters:NoSummary <

watch : Started
Building...
info: Microsoft.Hosting.Lifetime[14]
Now listening on: https://localhost:7081
info: Microsoft.Hosting.Lifetime[14]
Now listening on: http://localhost:5177
info: Microsoft.Hosting.Lifetime[0]
Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
Hosting environment: Development
info: Microsoft.Hosting.Lifetime[0]
Content root path: C:\Users\Niels\source\repos\dotnet-watch-attach
watch : Exited
watch : File changed: C:\Users\Niels\source\repos\dotnet-watch-attach\Controllers\WeatherForecastController.cs
watch : Started
Building...
info: Microsoft.Hosting.Lifetime[14]
Now listening on: https://localhost:7081
info: Microsoft.Hosting.Lifetime[14]
Now listening on: http://localhost:5177
info: Microsoft.Hosting.Lifetime[0]
Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
Hosting environment: Development
info: Microsoft.Hosting.Lifetime[0]
Content root path: C:\Users\Niels\source\repos\dotnet-watch-attach
watch : Exited
watch : File changed: C:\Users\Niels\source\repos\dotnet-watch-attach\Controllers\WeatherForecastController.cs
watch : Started
Building...
info: Microsoft.Hosting.Lifetime[14]
Now listening on: https://localhost:7081
info: Microsoft.Hosting.Lifetime[14]
Now listening on: http://localhost:5177
info: Microsoft.Hosting.Lifetime[0]
Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
Hosting environment: Development
info: Microsoft.Hosting.Lifetime[0]
Content root path: C:\Users\Niels\source\repos\dotnet-watch-attach

Steps to Reproduce

Repository to reproduce: here

Launch the configuration: .NET Core Attach

Expected Behavior

Debugger stays attached

Actual Behavior

Debugger gets terminated as dotnet watch run terminates the process it is attached to.

Logs

OmniSharp log

Starting OmniSharp server at 14/10/2021, 13:23:50 Target: c:\Users\Niels\source\repos\dotnet-watch-attach

OmniSharp server started.
Path: c:\Users\Niels.vscode\extensions\ms-dotnettools.csharp-1.23.16.omnisharp\1.37.16\OmniSharp.exe
PID: 12536

Starting OmniSharp on Windows 6.2.9200.0 (x64)
info: OmniSharp.Services.DotNetCliService
Checking the 'DOTNET_ROOT' environment variable to find a .NET SDK
info: OmniSharp.Services.DotNetCliService
Using the 'dotnet' on the PATH.
info: OmniSharp.Services.DotNetCliService
DotNetPath set to dotnet
info: OmniSharp.MSBuild.Discovery.MSBuildLocator
Located 2 MSBuild instance(s)
1: Visual Studio Enterprise 2019 16.10.31424.327 16.10.2 - "C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\MSBuild\Current\Bin"
2: StandAlone 17.0.0 - "c:\Users\Niels.vscode\extensions\ms-dotnettools.csharp-1.23.16.omnisharp\1.37.16.msbuild\Current\Bin"
info: OmniSharp.MSBuild.Discovery.MSBuildLocator
Registered MSBuild instance: Visual Studio Enterprise 2019 16.10.31424.327 16.10.2 - "C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\MSBuild\Current\Bin"
info: OmniSharp.WorkspaceInitializer
Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.CSharpFormattingWorkspaceOptionsProvider, Order: 0
info: OmniSharp.WorkspaceInitializer
Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.Completion.CompletionOptionsProvider, Order: 0
info: OmniSharp.WorkspaceInitializer
Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.RenameWorkspaceOptionsProvider, Order: 100
info: OmniSharp.WorkspaceInitializer
Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.ImplementTypeWorkspaceOptionsProvider, Order: 110
info: OmniSharp.WorkspaceInitializer
Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.BlockStructureWorkspaceOptionsProvider, Order: 140
info: OmniSharp.Cake.CakeProjectSystem
Detecting Cake files in 'c:\Users\Niels\source\repos\dotnet-watch-attach'.
info: OmniSharp.Cake.CakeProjectSystem
Could not find any Cake files
info: OmniSharp.MSBuild.ProjectSystem
No solution files found in 'c:\Users\Niels\source\repos\dotnet-watch-attach'
info: OmniSharp.MSBuild.ProjectManager
Queue project update for 'c:\Users\Niels\source\repos\dotnet-watch-attach\weather.csproj'
info: OmniSharp.Script.ScriptProjectSystem
Detecting CSX files in 'c:\Users\Niels\source\repos\dotnet-watch-attach'.
info: OmniSharp.Script.ScriptProjectSystem
Could not find any CSX files
info: OmniSharp.WorkspaceInitializer
Configuration finished.
info: OmniSharp.Stdio.Host
Omnisharp server running using Stdio at location 'c:\Users\Niels\source\repos\dotnet-watch-attach' on host 15580.
info: OmniSharp.MSBuild.ProjectManager
Loading project: c:\Users\Niels\source\repos\dotnet-watch-attach\weather.csproj
[warn]: OmniSharp.MSBuild.ProjectLoader
Targeting .NET 6.0 in Visual Studio 2019 is not supported.
info: OmniSharp.MSBuild.ProjectManager
Successfully loaded project file 'c:\Users\Niels\source\repos\dotnet-watch-attach\weather.csproj'.
c:\Users\Niels\source\repos\dotnet-watch-attach\weather.csproj
C:\Program Files\dotnet\sdk\6.0.100-rc.2.21505.57\Sdks\Microsoft.NET.Sdk\targets\Microsoft.NET.Sdk.DefaultItems.targets(134,5): Error: Targeting .NET 6.0 in Visual Studio 2019 is not supported.

Adding project 'c:\Users\Niels\source\repos\dotnet-watch-attach\weather.csproj'
info: OmniSharp.MSBuild.ProjectManager
Update project: weather
Received response for /v2/getcodeactions but could not find request.

C# log

None

## Environment information ##

VSCode version: 1.61.0
C# Extension: 1.23.16

Dotnet Information

.NET SDK (reflecting any global.json): Version: 6.0.100-rc.2.21505.57 Commit: ab39070116

Runtime Environment:
OS Name: Windows
OS Version: 10.0.19043
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\6.0.100-rc.2.21505.57\

Host (useful for support):
Version: 6.0.0-rc.2.21480.5
Commit: 6b11d64e7e

.NET SDKs installed:
2.0.2 [C:\Program Files\dotnet\sdk]
2.1.2 [C:\Program Files\dotnet\sdk]
2.1.201 [C:\Program Files\dotnet\sdk]
2.1.202 [C:\Program Files\dotnet\sdk]
2.1.300 [C:\Program Files\dotnet\sdk]
2.1.526 [C:\Program Files\dotnet\sdk]
3.1.120 [C:\Program Files\dotnet\sdk]
3.1.414 [C:\Program Files\dotnet\sdk]
5.0.104 [C:\Program Files\dotnet\sdk]
5.0.301 [C:\Program Files\dotnet\sdk]
5.0.303 [C:\Program Files\dotnet\sdk]
6.0.100-rc.1.21458.32 [C:\Program Files\dotnet\sdk]
6.0.100-rc.2.21505.57 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
Microsoft.AspNetCore.All 2.1.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.28 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.App 2.1.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.28 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 3.1.16 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 3.1.20 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 5.0.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 5.0.7 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 5.0.9 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 5.0.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 6.0.0-rc.2.21480.10 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 2.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.0.3 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.0.7 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.0.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.28 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 3.1.16 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 3.1.20 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 5.0.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 5.0.7 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 5.0.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 5.0.11 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 6.0.0-rc.2.21480.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 3.1.16 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 3.1.20 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 5.0.4 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 5.0.7 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 5.0.9 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 5.0.11 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 6.0.0-rc.2.21501.6 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

To install additional .NET runtimes or SDKs:
https://aka.ms/dotnet-download

Visual Studio Code Extensions

Extension	Author	Version
azure-account	ms-vscode	0.9.9
azure-pipelines	ms-azure-devops	1.191.0
azurerm-vscode-tools	msazurermtools	0.15.4
azurite	Azurite	3.14.2
beautify	HookyQR	1.5.0
bracket-pair-colorizer-2	CoenraadS	0.2.1
chat	karigari	0.35.0
clang-format	xaver	1.9.0
cpptools	ms-vscode	1.7.0
csharp	ms-dotnettools	1.23.16
debugger-for-edge	msjsdiag	1.0.15
discord-vscode	icrawl	5.7.0
EditorConfig	EditorConfig	0.16.4
gc-excelviewer	GrapeCity	3.0.44
githistory	donjayamanne	0.6.18
github-vscode-theme	GitHub	5.0.0
java	redhat	0.82.0
jupyter	ms-toolsai	2021.9.1001312534
jupyter-keymap	ms-toolsai	1.0.0
jupyter-renderers	ms-toolsai	1.0.3
ng-template	Angular	12.2.1
pdf	tomoki1207	1.1.0
powershell	ms-vscode	2021.10.0
prettier-vscode	esbenp	9.0.0
python	ms-python	2021.10.1336267007
rainbow-csv	mechatroner	1.9.1
remote-containers	ms-vscode-remote	0.202.4
remote-ssh	ms-vscode-remote	0.65.8
remote-ssh-edit	ms-vscode-remote	0.65.8
remote-wsl	ms-vscode-remote	0.58.2
shadered	dfranx	0.0.5
shaderlabformatter	litefeel	0.4.1
shaderlabvscodefree	amlovey	1.2.8
unity-debug	Unity	3.0.2
vetur	octref	0.34.1
vscode-azurefunctions	ms-azuretools	1.5.2
vscode-azureresourcegroups	ms-azuretools	0.4.0
vscode-commons	redhat	0.0.6
vscode-css-formatter	aeschli	1.0.1
vscode-dotnet-auto-attach	DennisMaxJung	1.1.1
vscode-dotnet-runtime	ms-dotnettools	1.3.0
vscode-eslint	dbaeumer	2.2.1
vscode-html-css	ecmel	1.10.2
vscode-java-debug	vscjava	0.36.0
vscode-java-dependency	vscjava	0.18.8
vscode-java-pack	vscjava	0.18.5
vscode-java-test	vscjava	0.32.0
vscode-maven	vscjava	0.34.0
vscode-nuget-gallery	patcx	0.0.24
vscode-peacock	johnpapa	3.10.1
vscode-proto3	zxh404	0.5.4
vscode-pylance	ms-python	2021.10.0
vscode-remote-extensionpack	ms-vscode-remote	0.21.0
vscode-xml	redhat	0.18.0
vscodeintellicode	VisualStudioExptTeam	1.2.14
vsliveshare	ms-vsliveshare	1.0.4991
vsliveshare-audio	ms-vsliveshare	0.1.91
vsliveshare-pack	ms-vsliveshare	0.4.0
wav-preview	sukumo28	1.8.0

[gregg-miskelly]

My current thought is the best way to implement this would be to add a special command that ran dotnet watch and scraped the output. When it saw a line about starting up a new process it would ask VS Code to debug. This could be done in this extension, or even another extension.

[Trottero]

@gregg-miskelly If with "ask VS Code to debug" you mean automatically attach a debugger to said process then yes, this is exactly what I'm looking for. If you mean that a box pops up asking the user to automatically attach to the newly spawned process then no, as this would still require user interaction every time a rebuild is done.

Regarding implementation, I'm okay with either. I know of the existence of DotNetAutoAttach But unfortunately I can't seem to get it to work. And it is also not really maintained right now.

[gregg-miskelly]

By "ask VS Code to debug" I mean use the VS Code debugging API to start a debug session.

[Trottero]

I've created a fairly crude extension which works for now. dotnet watch attach.

Would however still like to see this actually implemented :)

[JohnGalt1717]

+1 here. Really would like to close this inner loop and be able to do hot reload with VS Code like VS.net.

[ChrisProlls]

+1 for this as I mostly use VS Code for Blazor dev.

[murugaratham]

+1 for this as I mostly use VS Code for Blazor dev.

I've created an extension dotnet-watch, comes with debug config provider (auto generate launch.json), doesn't require manually setting up task.json.

Also examples with compound tasks for microservices

[Skrypt]

@Trottero solution works for me with Orchard Core.

The only thing is that it seems to have an issue finding the proper $msCompile problemMatcher.
I tried also @murugaratham extension but it seems to only launch in the console and I didn't find how to launch a browser automatically with it.

So, 2 questions :

Is there a plan to support this directly in VS Code? If not then ...
Anyone has an idea for a solution to the problemMatcher issue there is with @Trottero VS Code extension?

[MarcoMedrano]

I tryed both extensions proposed on Mac.

dotnet watch attach.

• Liked support vscode 'inputs'
• Doesnot support Mac, breakpoints aren't hit.

dotnet-watch

• Simpler to use
• Very slow when re-compiling (had to uninstall it, it s faster running the whole project again)