unittests: Fixes unit tests for Windows (part 11)

Currently, there are some unit tests that are failing on
Windows due to various reasons:

- Cannot remove a directory if there's a file open in that directory.
- Paths may have / or \ on Windows.

cmd/import-boss/main.go

@@ -428,6 +428,8 @@ func hasPathPrefix(path, prefix string) bool {
 	if prefix == "" || path == prefix {
 		return true
 	}
+	path = filepath.Clean(path)
+	prefix = filepath.Clean(prefix)
 	if !strings.HasSuffix(path, string(filepath.Separator)) {
 		prefix += string(filepath.Separator)
 	}

cmd/import-boss/main_test.go

@@ -19,7 +19,6 @@ package main
 import (
 	"path/filepath"
 	"reflect"
-	goruntime "runtime"
 	"strings"
 	"testing"
 
@@ -121,10 +120,6 @@ func TestHasTestFiles(t *testing.T) {
 }
 
 func TestPackageDir(t *testing.T) {
-	if goruntime.GOOS == "windows" {
-		// TODO: remove skip once the failing test has been fixed.
-		t.Skip("Skip failing test on Windows.")
-	}
 	cases := []struct {
 		input  *packages.Package
 		expect string
@@ -134,13 +129,13 @@ func TestPackageDir(t *testing.T) {
 			GoFiles:      []string{"/src/prj/file.go"},
 			IgnoredFiles: []string{"/otherdir/file.go"},
 		},
-		expect: "/src/prj",
+		expect: filepath.Clean("/src/prj"),
 	}, {
 		input: &packages.Package{
 			PkgPath:      "example.com/foo/bar/qux",
 			IgnoredFiles: []string{"/src/prj/file.go"},
 		},
-		expect: "/src/prj",
+		expect: filepath.Clean("/src/prj"),
 	}, {
 		input: &packages.Package{
 			PkgPath: "example.com/foo/bar/qux",
@@ -157,10 +152,6 @@ func TestPackageDir(t *testing.T) {
 }
 
 func TestHasPathPrefix(t *testing.T) {
-	if goruntime.GOOS == "windows" {
-		// TODO: remove skip once the failing test has been fixed.
-		t.Skip("Skip failing test on Windows.")
-	}
 	cases := []struct {
 		base   string
 		pfx    string
@@ -228,10 +219,6 @@ func checkAllErrorStrings(t *testing.T, errs []error, expect []string) {
 }
 
 func TestSimpleForward(t *testing.T) {
-	if goruntime.GOOS == "windows" {
-		// TODO: remove skip once the failing test has been fixed.
-		t.Skip("Skip failing test on Windows.")
-	}
 	pkgs, err := loadPkgs("./testdata/simple-fwd/aaa")
 	if err != nil {
 		t.Fatalf("unexpected failure: %v", err)

cmd/kubeadm/app/phases/certs/renewal/readwriter_test.go

@@ -23,7 +23,6 @@ import (
 	"net"
 	"os"
 	"path/filepath"
-	goruntime "runtime"
 	"testing"
 
 	"k8s.io/client-go/tools/clientcmd"
@@ -203,10 +202,6 @@ func writeTestKubeconfig(t *testing.T, dir, name string, caCert *x509.Certificat
 }
 
 func TestFileExists(t *testing.T) {
-	if goruntime.GOOS == "windows" {
-		// TODO: remove skip once the failing test has been fixed.
-		t.Skip("Skip failing test on Windows.")
-	}
 	tmpdir, err := os.MkdirTemp("", "")
 	if err != nil {
 		t.Fatalf("Couldn't create tmpdir: %v", err)
@@ -221,6 +216,10 @@ func TestFileExists(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Couldn't create tmpfile: %v", err)
 	}
+	if err := tmpfile.Close(); err != nil {
+		t.Fatalf("Couldn't close tmpfile: %v", err)
+	}
+
 	tests := []struct {
 		name     string
 		filename string
@@ -308,10 +307,6 @@ func TestPKICertificateReadWriterExists(t *testing.T) {
 }
 
 func TestKubeConfigReadWriterExists(t *testing.T) {
-	if goruntime.GOOS == "windows" {
-		// TODO: remove skip once the failing test has been fixed.
-		t.Skip("Skip failing test on Windows.")
-	}
 	tmpdir, err := os.MkdirTemp("", "")
 	if err != nil {
 		t.Fatalf("Couldn't create tmpdir: %v", err)
@@ -326,6 +321,10 @@ func TestKubeConfigReadWriterExists(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Couldn't create tmpfile: %v", err)
 	}
+	if err := tmpfile.Close(); err != nil {
+		t.Fatalf("Couldn't close tmpfile: %v", err)
+	}
+
 	tests := []struct {
 		name               string
 		kubeConfigFilePath string