Panics when error type uses generics

[mnrtks]

It panics when I check the error type with generics.

I installed errname with following command.

go install github.com/Antonboom/errname@latest

Reproduction code.

package customerror

var _ error = (*Error[string])(nil)

type Error[T ~string] struct {
	Code T
}

func (e *Error[T]) Error() string {
	return string(e.Code)
}

Command result.

$ errname ./...
panic: no specification for type

goroutine 211 [running]:
github.com/Antonboom/errname/pkg/analyzer.run.func3({0x136d2c8?, 0xc00020d590?})
	/Users/minoru.takase/pkg/mod/github.com/!antonboom/errname@v0.1.6/pkg/analyzer/analyzer.go:65 +0x174
golang.org/x/tools/go/ast/inspector.(*Inspector).Preorder(0xc0005acd68, {0x14edab0?, 0x1?, 0x117c2cd?}, 0xc000203998)
	/Users/minoru.takase/pkg/mod/golang.org/x/tools@v0.1.10/go/ast/inspector/inspector.go:77 +0x9a
github.com/Antonboom/errname/pkg/analyzer.run(0xc000597520)
	/Users/minoru.takase/pkg/mod/github.com/!antonboom/errname@v0.1.6/pkg/analyzer/analyzer.go:55 +0x1fd
golang.org/x/tools/go/analysis/internal/checker.(*action).execOnce(0xc0006aa280)
	/Users/minoru.takase/pkg/mod/golang.org/x/tools@v0.1.10/go/analysis/internal/checker/checker.go:728 +0x9fe
sync.(*Once).doSlow(0x0?, 0x1257b60?)
	/Users/minoru.takase/.asdf/installs/golang/1.18/go/src/sync/once.go:68 +0xc2
sync.(*Once).Do(...)
	/Users/minoru.takase/.asdf/installs/golang/1.18/go/src/sync/once.go:59
golang.org/x/tools/go/analysis/internal/checker.(*action).exec(0xc00012e420?)
	/Users/minoru.takase/pkg/mod/golang.org/x/tools@v0.1.10/go/analysis/internal/checker/checker.go:616 +0x3d
golang.org/x/tools/go/analysis/internal/checker.execAll.func1(0x0?)
	/Users/minoru.takase/pkg/mod/golang.org/x/tools@v0.1.10/go/analysis/internal/checker/checker.go:604 +0x25
created by golang.org/x/tools/go/analysis/internal/checker.execAll
	/Users/minoru.takase/pkg/mod/golang.org/x/tools@v0.1.10/go/analysis/internal/checker/checker.go:610 +0x165

[Antonboom]

Thank u!
I'll try to fix this next weekend.

[Antonboom]

@mnrtks, please check :)

[mnrtks]

It worked! Thank you!