From 360cc86ce5cb1d3040a886a864c905b153dc0eca Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=90=B4=E6=A2=93=E9=93=AD?=
 <83150084+NgZiming@users.noreply.github.com>
Date: Fri, 24 Jun 2022 22:09:40 +0800
Subject: [PATCH] fix: panic when environment variables are empty
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On mac OS, environment variables like: OLDPWD are usually empty. May trigger panics like:
```bash
😄  minikube v1.26.0 on Darwin 11.6.5
panic: runtime error: index out of range [1] with length 1

goroutine 1 [running]:
k8s.io/minikube/cmd/minikube/cmd.displayEnviron({0xc000a69a40?, 0x1c, 0xb?})
	/private/tmp/minikube-20220623-65769-c2xa25/cmd/minikube/cmd/start.go:445 +0x252
k8s.io/minikube/cmd/minikube/cmd.runStart(0x7316040?, {0x5d07e13?, 0x0?, 0x0?})
	/private/tmp/minikube-20220623-65769-c2xa25/cmd/minikube/cmd/start.go:157 +0x245
github.com/spf13/cobra.(*Command).execute(0x7316040, {0x73736d8, 0x0, 0x0})
	/Users/brew/Library/Caches/Homebrew/go_mod_cache/pkg/mod/github.com/spf13/cobra@v1.5.0/command.go:876 +0x67b
github.com/spf13/cobra.(*Command).ExecuteC(0x7313fc0)
	/Users/brew/Library/Caches/Homebrew/go_mod_cache/pkg/mod/github.com/spf13/cobra@v1.5.0/command.go:990 +0x3b4
github.com/spf13/cobra.(*Command).Execute(...)
	/Users/brew/Library/Caches/Homebrew/go_mod_cache/pkg/mod/github.com/spf13/cobra@v1.5.0/command.go:918
k8s.io/minikube/cmd/minikube/cmd.Execute()
	/private/tmp/minikube-20220623-65769-c2xa25/cmd/minikube/cmd/root.go:170 +0xca5
main.main()
	/private/tmp/minikube-20220623-65769-c2xa25/cmd/minikube/main.go:88 +0x255
```
---
 cmd/minikube/cmd/start.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/cmd/minikube/cmd/start.go b/cmd/minikube/cmd/start.go
index 96dd95bb84c0..3a9f6ca313c8 100644
--- a/cmd/minikube/cmd/start.go
+++ b/cmd/minikube/cmd/start.go
@@ -441,6 +441,9 @@ func displayVersion(version string) {
 func displayEnviron(env []string) {
 	for _, kv := range env {
 		bits := strings.SplitN(kv, "=", 2)
+		if len(bits) < 2 {
+			continue
+		}
 		k := bits[0]
 		v := bits[1]
 		if strings.HasPrefix(k, "MINIKUBE_") || k == constants.KubeconfigEnvVar {