add tests (thanks to @ts2909)

* copied from 6c031db617

basepath_test.go

@@ -5,6 +5,7 @@ import (
 	"path/filepath"
 	"runtime"
 	"testing"
+	"fmt"
 )
 
 func TestBasePath(t *testing.T) {
@@ -140,3 +141,53 @@ func TestNestedBasePaths(t *testing.T) {
 		}
 	}
 }
+
+
+func TestBasePathOpenFile(t *testing.T) {
+	baseFs := &MemMapFs{}
+	baseFs.MkdirAll("/base/path/tmp", 0777)
+	bp := NewBasePathFs(baseFs, "/base/path")
+	f, err := bp.OpenFile("/tmp/file.txt", os.O_CREATE, 0600)
+	if err != nil {
+		t.Fatalf("failed to open file: %v", err)
+	}
+	if filepath.Dir(f.Name()) != "/tmp" {
+		t.Fatalf("realpath leaked: %s", f.Name())
+	}
+}
+
+func TestBasePathCreate(t *testing.T) {
+	baseFs := &MemMapFs{}
+	baseFs.MkdirAll("/base/path/tmp", 0777)
+	bp := NewBasePathFs(baseFs, "/base/path")
+	f, err := bp.Create("/tmp/file.txt")
+	if err != nil {
+		t.Fatalf("failed to create file: %v", err)
+	}
+	if filepath.Dir(f.Name()) != "/tmp" {
+		t.Fatalf("realpath leaked: %s", f.Name())
+	}
+}
+
+func TestBasePathTempFile(t *testing.T) {
+	baseFs := &MemMapFs{}
+	baseFs.MkdirAll("/base/path/tmp", 0777)
+	bp := NewBasePathFs(baseFs, "/base/path")
+
+	tDir, err := TempDir(bp, "/tmp", "")
+	if err != nil {
+		t.Fatalf("Failed to TempDir: %v", err)
+	}
+	fmt.Println(tDir)
+	if filepath.Dir(tDir) != "/tmp" {
+		t.Fatalf("Tempdir realpath leaked: %s", tDir)
+	}
+	tempFile, err := TempFile(bp, tDir, "")
+	if err != nil {
+		t.Fatalf("Failed to TempFile: %v", err)
+	}
+	defer tempFile.Close()
+	if expected, actual := tDir, filepath.Dir(tempFile.Name()); expected != actual {
+		t.Fatalf("TempFile realpath leaked: expected %s, got %s", expected, actual)
+	}
+}