Replace os.Setenv with testing.T.Setenv in tests

T.Setenv ensures that the environment is returned to its prior state
when the test ends. It also panics when called from a parallel test to
prevent racy test interdependencies.

test/conformance/image/go-runner/env_test.go

@@ -32,7 +32,7 @@ func TestEnv(t *testing.T) {
 			desc: "OS env",
 			env:  &osEnv{},
 			preHook: func() {
-				os.Setenv("key1", "1")
+				t.Setenv("key1", "1")
 			},
 			expect: map[string]string{"key1": "1"},
 		}, {

test/integration/serving/serving_test.go

@@ -83,10 +83,8 @@ func TestComponentSecureServingAndAuth(t *testing.T) {
 
 	// Insulate this test from picking up in-cluster config when run inside a pod
 	// We can't assume we have permissions to write to /var/run/secrets/... from a unit test to mock in-cluster config for testing
-	originalHost := os.Getenv("KUBERNETES_SERVICE_HOST")
-	if len(originalHost) > 0 {
-		os.Setenv("KUBERNETES_SERVICE_HOST", "")
-		defer os.Setenv("KUBERNETES_SERVICE_HOST", originalHost)
+	if len(os.Getenv("KUBERNETES_SERVICE_HOST")) > 0 {
+		t.Setenv("KUBERNETES_SERVICE_HOST", "")
 	}
 
 	// authenticate to apiserver via bearer token

test/integration/volumescheduling/volume_binding_test.go

@@ -21,7 +21,6 @@ package volumescheduling
 import (
 	"context"
 	"fmt"
-	"os"
 	"strconv"
 	"strings"
 	"testing"
@@ -427,10 +426,7 @@ func testVolumeBindingStress(t *testing.T, schedulerResyncPeriod time.Duration,
 
 	// Set max volume limit to the number of PVCs the test will create
 	// TODO: remove when max volume limit allows setting through storageclass
-	if err := os.Setenv(nodevolumelimits.KubeMaxPDVols, fmt.Sprintf("%v", podLimit*volsPerPod)); err != nil {
-		t.Fatalf("failed to set max pd limit: %v", err)
-	}
-	defer os.Unsetenv(nodevolumelimits.KubeMaxPDVols)
+	t.Setenv(nodevolumelimits.KubeMaxPDVols, fmt.Sprintf("%v", podLimit*volsPerPod))
 
 	scName := &classWait
 	if dynamic {

test/typecheck/main_test.go

@@ -32,7 +32,7 @@ var goBinary = flag.String("go", "", "path to a `go` binary")
 func TestVerify(t *testing.T) {
 	// x/tools/packages is going to literally exec `go`, so it needs some
 	// setup.
-	setEnvVars()
+	setEnvVars(t)
 
 	tcs := []struct {
 		path   string
@@ -57,17 +57,18 @@ func TestVerify(t *testing.T) {
 	}
 }
 
-func setEnvVars() {
+func setEnvVars(t testing.TB) {
+	t.Helper()
 	if *goBinary != "" {
 		newPath := filepath.Dir(*goBinary)
 		curPath := os.Getenv("PATH")
 		if curPath != "" {
 			newPath = newPath + ":" + curPath
 		}
-		os.Setenv("PATH", newPath)
+		t.Setenv("PATH", newPath)
 	}
 	if os.Getenv("HOME") == "" {
-		os.Setenv("HOME", "/tmp")
+		t.Setenv("HOME", "/tmp")
 	}
 }