[BUG] go.buildFlags with -ldflags causes incompatible behavior between "run test" and "debug test" CodeLens

[vrv3814]

What version of Go, VS Code & VS Code Go extension are you using?

Version Information

• Run go version to get version of Go from the VS Code integrated terminal.
  • go version go1.25.3 linux/amd64
• Run gopls -v version to get version of Gopls from the VS Code integrated terminal.

         Build info
         ----------
         golang.org/x/tools/gopls v0.20.0
             golang.org/x/tools/gopls@v0.20.0 h1:fxOYZXKl6IsOTKIh6IgjDbIDHlr5btOtOUkrGOgFDB4=
             github.com/BurntSushi/toml@v1.5.0 h1:W5quZX/G/csjUnuI8SUYlsHs9M38FC7znL0lIO+DvMg=
             github.com/fatih/camelcase@v1.0.0 h1:hxNvNX/xYBp0ovncs8WyWZrOrpBNub/JfaMvbURyft8=
             github.com/fatih/gomodifytags@v1.17.1-0.20250423142747-f3939df9aa3c h1:dDSgAjoOMp8da3egfz0t2S+t8RGOpEmEXZubcGuc0Bg=
             github.com/fatih/structtag@v1.2.0 h1:/OdNE99OxoI/PqaW/SuSK9uxxT3f/tcSZgon/ssNSx4=
             github.com/fsnotify/fsnotify@v1.9.0 h1:2Ml+OJNzbYCTzsxtv8vKSFD9PbJjmhYF14k/jKC7S9k=
             github.com/google/go-cmp@v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
             golang.org/x/exp/typeparams@v0.0.0-20250620022241-b7579e27df2b h1:KdrhdYPDUvJTvrDK9gdjfFd6JTk8vA1WJoldYSi0kHo=
             golang.org/x/mod@v0.26.0 h1:EGMPT//Ezu+ylkCijjPc+f4Aih7sZvaAr+O3EHBxvZg=
             golang.org/x/sync@v0.16.0 h1:ycBJEhp9p4vXvUZNszeOq0kGTPghopOL8q0fq3vstxw=
             golang.org/x/sys@v0.34.0 h1:H5Y5sJ2L2JRdyv7ROF1he/lPdvFsd0mJHFw2ThKHxLA=
             golang.org/x/telemetry@v0.0.0-20250710130107-8d8967aff50b h1:DU+gwOBXU+6bO0sEyO7o/NeMlxZxCZEvI7v+J4a1zRQ=
             golang.org/x/text@v0.27.0 h1:4fGWRpyh641NLlecmyl4LOe6yDdfaYNrGb2zdfo4JV4=
             golang.org/x/tools@v0.35.1-0.20250728180453-01a3475a31bc h1:ZRKyKRJl/YEWl9ScZwd6Ua6xSt7DE6tHp1I3ucMroGM=
             golang.org/x/vuln@v1.1.4 h1:Ju8QsuyhX3Hk8ma3CesTbO8vfJD9EvUBgHvkxHBzj0I=
             honnef.co/go/tools@v0.7.0-0.dev.0.20250523013057-bbc2f4dd71ea h1:fj8r9irJSpolAGUdZBxJIRY3lLc4jH2Dt4lwnWyWwpw=
             mvdan.cc/gofumpt@v0.8.0 h1:nZUCeC2ViFaerTcYKstMmfysj6uhQrA2vJe+2vwGU6k=
             mvdan.cc/xurls/v2@v2.6.0 h1:3NTZpeTxYVWNSokW3MKeyVkz/j7uYXYiMtXRUfmjbgI=
         go: go1.25.3
  
     
  
  

• Run code -v or code-insiders -v to get version of VS Code or VS Code Insiders.
  .106.3 bf9252a2fb45be6893dd8870c0bf37e2e1766d61 x64
• Check your installed extensions to get the version of the VS Code Go extension
  • Version 0.50.0

Describe the bug

When using -ldflags in test configuration, the "run test" and "debug test" CodeLens buttons handle flags inconsistently, making it impossible to configure flags that work for both operations.

Scenario 1: Using go.buildFlags with quoted value
settings.json:

{
    "go.buildFlags": [
         "-ldflags", "'-X github.com/org/driver-device/internal/info.version=v25.8.0'"
    ]
}

✅ Debug test works
❌ Run test fails with:

Running tool: /usr/local/go/bin/go test -timeout 30s -run ^TestReconcile_Function$ github.com/org/controller/internal/tefrol -ldflags '-X github.com/org/driver-device/internal/info.version=v25.8.0'

invalid value "'-X github.com/org/driver-device/internal/info.version=v25.8.0'" for flag -ldflags: parameter may not start with quote character '
usage: go test [build/test flags] [packages] [build/test flags & test binary flags]
Run 'go help test' and 'go help testflag' for details.

Scenario 2: Using go.buildFlags without quotes
settings.json:

{
    "go.buildFlags": [
         "-ldflags", "-X github.com/org/driver-device/internal/info.version=v25.8.0"
    ]
}

✅ Run test works
❌ Debug test fails in packages with subdirectories with:

Build Error: go test -c -o /home/user/controller/internal/tefrol/__debug_bin1049253809 -gcflags all=-N -l -ldflags -X github.com/org/driver-device/internal/info.version=v25.8.0 .
with multiple packages, -o must refer to a directory or /dev/null (exit status 1)

[vrv3814]

FYI, go binary absolutely has no problems recognizing quotes when used in combination with -ldflags but extension doesn't seem to think so?
Ex: See the output when I run it directly from command line

$ go test -c -o /home/user/controller/internal/tefrol/__debug_bin2891619867 -gcflags all="-N -l" -ldflags '-X github.com/org/driver-device/internal/info.version=v25.8.0' .
$ echo $?
0

$ /usr/local/go/bin/go test -timeout 30s -run ^TestReconcile_Function$ github.com/org/controller/internal/tefrol -ldflags '-X github.com/org/driver-device/internal/info.version=v25.8.0'
ok      github.com/org/controller/internal/tefrol        (cached)

[adonovan]

cc: @h9jiang

[h9jiang]

I have found multiple issue relevant to the issue you are mentioning here, I'm not aware of them until now. Thanks for the reminder.

#1836, #1831, go-delve/delve#2718

I think the problem might be, delve accept build flags through delve config

OK "buildFlags":"-ldflags='-X main.version=v1.0.0'" 
NOT OK "buildFlags":"-ldflags=-X main.version=v1.0.0" 

But the go test simply attach the flag to the go test command. And why is child process spawn is not working the same way as shell....

go test -test.fullpath=true -timeout 30s -run ^TestVersion$ bug-repro -ldflags='-X main.version=v1.0.0'

OK in SHELL
NOT OK in cp.Spawn

We should consolidate on the flag format. At this point, any change would introduce some breaking behavior to the extension users. Allow me to read more about how delve is interpreting the flag and see if we could settle on a single form of flags....

[vrv3814]

Right @h9jiang I forgot to add the same issue also happens if I use go.testFlags instead of go.buildFlags in settings.json

[vrv3814]

If it helps, you could probably use maybeJoinFlags based on dlv version to decide how quotes are handled?