affected/package: go1.20.1 When obtaining a "nil" value after defining an interface, it is not recognized as an empty value during condition checks.

[vela-security]

What version of Go are you using (go version)?

$ go version
go version go1.20.1 windows/amd64

Does this issue reproduce with the latest release?

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
set GO111MODULE=on
set GOARCH=amd64
set GOBIN=
set GOCACHE=C:\Users\vela\AppData\Local\go-build
set GOENV=C:\Users\vela\AppData\Roaming\go\env
set GOEXE=.exe
set GOEXPERIMENT=
set GOFLAGS=
set GOHOSTARCH=amd64
set GOHOSTOS=windows
set GOINSECURE=
set GOMODCACHE=C:\Users\vela\go\pkg\mod
set GONOPROXY=
set GONOSUMDB=
set GOOS=windows
set GOPATH=C:\Users\vela\go
set GOPRIVATE=
set GOPROXY=https://goproxy.cn,direct
set GOROOT=C:\Program Files\Go
set GOSUMDB=sum.golang.org
set GOTMPDIR=
set GOTOOLDIR=C:\Program Files\Go\pkg\tool\windows_amd64
set GOVCS=
set GOVERSION=go1.20.1
set GCCGO=gccgo
set GOAMD64=v1
set AR=ar
set CC=gcc
set CXX=g++
set CGO_ENABLED=0
set GOMOD=NUL
set GOWORK=
set CGO_CFLAGS=-O2 -g
set CGO_CPPFLAGS=
set CGO_CXXFLAGS=-O2 -g
set CGO_FFLAGS=-O2 -g
set CGO_LDFLAGS=-O2 -g
set PKG_CONFIG=pkg-config
set GOGCCFLAGS=-m64 -fno-caret-diagnostics -Qunused-arguments -Wl,--no-gc-sections -fmessage-length=0 -fdebug-prefix-map=C:\Users\vela\AppData\Local\Temp\go-build236094550=/tmp/go-build -gno-record-gcc-switches

What did you do?

check Nil fail

In the context of Github issues, while inspecting the returned objects of an API, I found that using the API's definition to retrieve a "nil" value doesn't register as an empty value during condition checks. This can easily lead to bugs and errors, so I hope it can be corrected.

package web

import "testing"

type A struct {
}

func (*A) View() {}

type Show interface {
	View()
}

func NewA() *A {
	return nil
}

func NewShow() Show {
	return NewA()
}

func TestNil(t *testing.T) {
	a := NewShow()

	if a == nil {
		t.Log("a is nil")
		return
	}

	t.Log("a not is nil")

}

test output

    API server listening at: 127.0.0.1:61858
    === RUN   TestNil
        interface_test.go:30: a not is nil
    --- PASS: TestNil (0.00s)

What did you expect to see?

a is nil

[fzipp]

https://go.dev/doc/faq#nil_error

[seankhliao]

Unlike many projects, the Go project does not use GitHub Issues for general discussion or asking questions. GitHub Issues are used for tracking bugs and proposals only.

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