panic when import `golang.org/x/text`

[WL]

The following program sample.go triggers a panic:

package main

import (
	"golang.org/x/text/language"
	"log"
)

func main() {
	log.Println(language.English)
}

Expected result:

$ go run ./sample.go

2021/06/19 21:42:46 en

Got: panic run: language: tag is not well-formed
Links to panic line number

• golang.org/x/text/internal/language/tags.go:12
• golang.org/x/text/internal/language/compact/compact.go:59

$ yaegi ./sample.go


/Users/wlun/go/src/golang.org/x/text/internal/language/tags.go:12:3: panic
/Users/wlun/go/src/golang.org/x/text/internal/language/compact/compact.go:59:20: panic
run: language: tag is not well-formed
goroutine 1 [running]:
runtime/debug.Stack(0x1, 0xc0013c6800, 0x40)
	/usr/local/Cellar/go/1.16.3/libexec/src/runtime/debug/stack.go:24 +0x9f
github.com/traefik/yaegi/interp.(*Interpreter).eval.func1(0xc00223fc18)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/interp.go:503 +0xc8
panic(0x1b3a800, 0xc001a3dc20)
	/usr/local/Cellar/go/1.16.3/libexec/src/runtime/panic.go:965 +0x1b9
github.com/traefik/yaegi/interp.runCfg.func1(0xc001bccfd0, 0xc002052100, 0xc00223de68)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/run.go:185 +0x253
panic(0x1b3a800, 0xc001a3dc20)
	/usr/local/Cellar/go/1.16.3/libexec/src/runtime/panic.go:965 +0x1b9
github.com/traefik/yaegi/interp.runCfg.func1(0xc001bcd130, 0xc001295900, 0xc00223dc58)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/run.go:185 +0x253
panic(0x1b3a800, 0xc001a3dc20)
	/usr/local/Cellar/go/1.16.3/libexec/src/runtime/panic.go:965 +0x1b9
github.com/traefik/yaegi/interp._panic.func1(0xc001bcd130, 0xc0018fa550)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/run.go:838 +0x7f
github.com/traefik/yaegi/interp.runCfg(0xc001295900, 0xc001bcd130)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/run.go:191 +0x87
github.com/traefik/yaegi/interp.call.func7(0xc001bccfd0, 0xc0015b16c0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/run.go:1272 +0xd05
github.com/traefik/yaegi/interp.runCfg(0xc002052100, 0xc001bccfd0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/run.go:191 +0x87
github.com/traefik/yaegi/interp.(*Interpreter).run(0xc000366000, 0xc001ea5800, 0xc000368000)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/run.go:122 +0x2b0
github.com/traefik/yaegi/interp.(*Interpreter).importSrc(0xc000366000, 0x0, 0x0, 0xc001d0ac91, 0x2b, 0x1078e01, 0xc0004a6158, 0x8, 0x0, 0x0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/src.go:156 +0xad9
github.com/traefik/yaegi/interp.(*Interpreter).gta.func1(0xc0014ffd00, 0xc00223ec48)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/gta.go:222 +0x12e5
github.com/traefik/yaegi/interp.(*node).Walk(0xc0014ffd00, 0xc00223ec48, 0x0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/interp.go:232 +0xb5
github.com/traefik/yaegi/interp.(*node).Walk(0xc0014fef00, 0xc00223ec48, 0x0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/interp.go:236 +0x66
github.com/traefik/yaegi/interp.(*node).Walk(0xc0014fe800, 0xc00223ec48, 0x0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/interp.go:236 +0x66
github.com/traefik/yaegi/interp.(*Interpreter).gta(0xc000366000, 0xc0014fe800, 0xc00011e580, 0x1a, 0xc000488041, 0x1a, 0xc001bbfc28, 0x8, 0xc0014fe800, 0x0, ...)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/gta.go:20 +0x21f
github.com/traefik/yaegi/interp.(*Interpreter).importSrc(0xc000366000, 0x0, 0x0, 0xc000488041, 0x1a, 0x1, 0x16, 0xc000211300, 0xca, 0xc000212510)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/src.go:100 +0xf57
github.com/traefik/yaegi/interp.(*Interpreter).gta.func1(0xc000210400, 0x0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/gta.go:222 +0x12e5
github.com/traefik/yaegi/interp.(*node).Walk(0xc000210400, 0xc00223f9b8, 0x0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/interp.go:232 +0xb5
github.com/traefik/yaegi/interp.(*node).Walk(0xc000210300, 0xc00223f9b8, 0x0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/interp.go:236 +0x66
github.com/traefik/yaegi/interp.(*node).Walk(0xc000210100, 0xc00223f9b8, 0x0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/interp.go:236 +0x66
github.com/traefik/yaegi/interp.(*Interpreter).gta(0xc000366000, 0xc000210100, 0xc00020d9d0, 0x4, 0xc00020d9d0, 0x4, 0x10, 0xc000200240, 0x0, 0xc0002063e0, ...)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/gta.go:20 +0x21f
github.com/traefik/yaegi/interp.(*Interpreter).gtaRetry(0xc000366000, 0xc00223fb88, 0x1, 0x1, 0xc00020d9d0, 0x4, 0xc00020d9d0, 0x4)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/gta.go:311 +0x12c
github.com/traefik/yaegi/interp.(*Interpreter).eval(0xc000366000, 0xc0002c6310, 0x6e, 0x7ffeefbffb2e, 0x9, 0x0, 0x0, 0x0, 0x0, 0x0, ...)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/interp.go:525 +0x2a5
github.com/traefik/yaegi/interp.(*Interpreter).EvalPath(0xc000366000, 0x7ffeefbffb2e, 0x9, 0xc0002c6200, 0x6e, 0x0, 0x0, 0xc0001b1cb0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/interp/interp.go:417 +0x105
main.runFile(0xc000366000, 0x7ffeefbffb2e, 0x9, 0x0, 0x1, 0x0)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/cmd/yaegi/run.go:139 +0xb1
main.run(0xc000032050, 0x1, 0x1, 0xc00000a501, 0xc000001680)
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/cmd/yaegi/run.go:102 +0x99d
main.main()
	/Users/wlun/go/pkg/mod/github.com/traefik/yaegi@v0.9.18/cmd/yaegi/yaegi.go:144 +0x415

[WL]

any ETA for this ? or any alternative can do for now? needed for a plugin

[Marc Vertes]

Sorry, I cannot provide ETAs.

[WL]

Sorry to ping, any updates on this?

[WL]

Tried with the latest release, it doesn't panic, but the output is not expected. Could you please help to check @nrwiersma

Expected

go run sample.go

2021/09/16 18:16:57 en

Actual output

yaegi ./sample.go


2021/09/16 18:16:59 {134 134 <nil>}

[Nicholas Wiersma]

It is not possible for yaegi to have to output you want, as the struct generated for language.English does not actually have a String method (this is a limitation in Go reflect) and is therefore not a Stringer which is what this output is relying on.

[WL]

any suggestion or alternative that I can do from here? @nrwiersma

[Nicholas Wiersma]

You have 3 option:

1. Change Go, the issue is here: golang/go#16522
2. Move golang.org/x/text/language from be interpreted to being native using yaegi Export and Use
3. Change your code

But I cannot help you further than that.

[WL]

@nrwiersma thanks a lot