"Go: Generate Unit Tests For Function" does not handle generics

[haraldrudell]

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 go1.22.3 darwin/arm64

• Run gopls -v version to get version of Gopls from the VS Code integrated terminal.

  • golang.org/x/tools/gopls v0.15.3
    golang.org/x/tools/gopls@v0.15.3 h1:zbdOidFrPTc8Bx0YrN5QKgJ0zCjyGi0L27sKQ/bDG5o=
    github.com/BurntSushi/toml@v1.2.1 h1:9F2/+DoOYIOksmaJFPw1tGFy1eDnIJXg+UHjuD8lTak=
    github.com/google/go-cmp@v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
    golang.org/x/exp/typeparams@v0.0.0-20221212164502-fae10dda9338 h1:2O2DON6y3XMJiQRAS1UWU+54aec2uopH3x7MAiqGW6Y=
    golang.org/x/mod@v0.15.0 h1:SernR4v+D55NyBH2QiEQrlBAnj1ECL6AGrA5+dPaMY8=
    golang.org/x/sync@v0.6.0 h1:5BMeUDZ7vkXGfEr1x9B4bRcTH4lpkTkpdh0T/J+qjbQ=
    golang.org/x/telemetry@v0.0.0-20240209200032-7b892fcb8a78 h1:vcVnuftN4J4UKLRcgetjzfU9FjjgXUUYUc3JhFplgV4=
    golang.org/x/text@v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
    golang.org/x/tools@v0.18.1-0.20240412183611-d92ae0781217 h1:uH9jJYgeLCvblH0S+03kFO0qUDxRkbLRLFiKVVDl7ak=
    golang.org/x/vuln@v1.0.1 h1:KUas02EjQK5LTuIx1OylBQdKKZ9jeugs+HiqO5HormU=
    honnef.co/go/tools@v0.4.6 h1:oFEHCKeID7to/3autwsWfnuv69j3NsfcXbvJKuIcep8=
    mvdan.cc/gofumpt@v0.6.0 h1:G3QvahNDmpD+Aek/bNOLrFR2XC6ZAdo62dZu65gmwGo=
    mvdan.cc/xurls/v2@v2.5.0 h1:lyBNOm8Wo71UknhUs4QTFUNNMyxy2JEIaKKo0RWOh+8=
    go: go1.22.1

• Run code -v or code-insiders -v to get version of VS Code or VS Code Insiders.

  • 1.90.0

• Check your installed extensions to get the version of the VS Code Go extension

  • Go v0.41.4

• Run Ctrl+Shift+P (Cmd+Shift+P on Mac OS) > Go: Locate Configured Go Tools command.

  • Tools Configuration

Environment

GOBIN: undefined
toolsGopath:
gopath: /Users/foxyboy/go
GOROOT: /opt/homebrew/Cellar/go/1.22.3/libexec
PATH: /Users/foxyboy/bin:/Users/foxyboy/go/bin:/opt/bin:/opt/homebrew/bin:/opt/homebrew/sbin:/Users/foxyboy/Library/Android/sdk/platform-tools:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin

Tools

go:	/opt/homebrew/bin/go: go version go1.22.3 darwin/arm64

gopls:	/Users/foxyboy/go/bin/gopls	(version: v0.15.3 built with go: go1.22.1)
gotests:	/Users/foxyboy/go/bin/gotests	(version: v1.6.0 built with go: go1.22.0)
gomodifytags:	/Users/foxyboy/go/bin/gomodifytags	(version: v1.16.0 built with go: go1.22.0)
impl:	/Users/foxyboy/go/bin/impl	(version: v1.1.0 built with go: go1.22.0)
goplay:	/Users/foxyboy/go/bin/goplay	(version: v1.0.0 built with go: go1.22.0)
dlv:	/Users/foxyboy/go/bin/dlv	(version: v1.22.0 built with go: go1.22.0)
staticcheck:	/Users/foxyboy/go/bin/staticcheck	(version: v0.4.6 built with go: go1.22.0)

Go env

Workspace Folder (parl): /opt/sw/parl

GO111MODULE=''
GOARCH='arm64'
GOBIN=''
GOCACHE='/Users/foxyboy/Library/Caches/go-build'
GOENV='/Users/foxyboy/Library/Application Support/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='arm64'
GOHOSTOS='darwin'
GOINSECURE=''
GOMODCACHE='/Users/foxyboy/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='darwin'
GOPATH='/Users/foxyboy/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/opt/homebrew/Cellar/go/1.22.3/libexec'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/opt/homebrew/Cellar/go/1.22.3/libexec/pkg/tool/darwin_arm64'
GOVCS=''
GOVERSION='go1.22.3'
GCCGO='gccgo'
AR='ar'
CC='cc'
CXX='c++'
CGO_ENABLED='1'
GOMOD='/opt/sw/parl/go.mod'
GOWORK='/opt/sw/parl/go.work'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'
GOGCCFLAGS='-fPIC -arch arm64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -ffile-prefix-map=/var/folders/sq/0x1_9fyn1bv907s7ypfryt1c0000gn/T/go-build2682538169=/tmp/go-build -gno-record-gcc-switches -fno-common'

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Share all the settings with the go. or ["go"] or gopls prefixes.

Describe the bug

A clear and concise description of what the bug.
A clear and concise description of what you expected to happen.

Steps to reproduce the behavior:

1. In the below program, right-click the “return” line and select “Go: Generate Unit Test For Function”
2. BUG: toaster: “No tests generated for ….go”

EXPECTED:
a *_test.go file to be created

It has been requested by others to explain why tests are not generated, and the statement has been that gopls does not provide why it is not creating tests

Regardless, tests should be created

/*
© 2024–present Harald Rudell <harald.rudell@gmail.com> https://haraldrudell.github.io/haraldrudell/)
ISC License
*/

package parl

type AnyCount[T any] struct{}

func (a AnyCount[T]) Count() (count int) {
	return
}

[adonovan]

This VS Code command invokes the gotests command as a subprocess. The generateTests function in vscode-go/src/goGenerateTests.ts doesn't use the stderr value returned by child_process.execFile, so the explanation is discarded. It should at least be printed to the log.

[hyangah]

The following is the exact command the extension uses to call gotests,
and the message shown in the prompt is the only output/feedback coming from the gotests tool
for this specific case

$ gotests -w -only ^AnyCount[T]Count$ /Users/hakim/xx/main.go
No tests generated for /Users/hakim/xx/main.go

The pattern passed to the -only flag param is wrong, but also, gotests nor the extension's integration doesn't support generics.

Related: cweill/gotests#165
Proposed plan: migrate the functionality to gopls - golang/go#47479 and #1594

[hyangah]

Thanks for the report @haraldrudell
Closing since the root cause is in the upstream tool, and we hope to provide better error messages when gopls takes over the functionality.