common: add GetParentDir() function

common/path.go

@@ -1,6 +1,8 @@
 package common
 
 import (
+	"errors"
+	"fmt"
 	"path/filepath"
 	"strings"
 
@@ -47,3 +49,18 @@ func IsAbsWindows(path string) bool {
 
 	return false
 }
+
+// GetParentDir returns the parent directory of the given path, it will not change the separate character
+func GetParentDir(absPath string) (string, error) {
+	if !IsAbs(absPath) {
+		return constant.EmptyString, errors.New(fmt.Sprintf("path must be an absolute path, %s is not valid", absPath))
+	}
+
+	for i := len(absPath) - 1; i > constant.ZeroInt; i-- {
+		if absPath[i] == '/' || absPath[i] == '\\' {
+			return absPath[:i], nil
+		}
+	}
+
+	return constant.SlashString, nil
+}

common/path_test.go

@@ -9,7 +9,7 @@ import (
 const (
 	testUnixAbsPath     = "/data/mysql/data/"
 	testUnixRelPath     = "data/mysql/"
-	testWindowsAbsPathA = `C:\data\mysql\data\`
+	testWindowsAbsPathA = `C:\data\mysql\data`
 	testWindowsAbsPathB = `C:/data/mysql/data/`
 	testWindowsRelPath  = `data\mysql\data\`
 )
@@ -48,3 +48,19 @@ func TestIsAbsWindows(t *testing.T) {
 	asst.True(IsAbsWindows(testWindowsAbsPathB), "test IsAbsWindows() failed")
 	asst.False(IsAbsWindows(testWindowsRelPath), "test IsAbsWindows() failed")
 }
+
+func TestGetParentDir(t *testing.T) {
+	asst := assert.New(t)
+
+	dir, err := GetParentDir(testUnixRelPath)
+	asst.NotNil(err, "test GetParentDir() failed")
+	dir, err = GetParentDir(testUnixAbsPath)
+	asst.Nil(err, "test GetParentDir() failed")
+	t.Log(dir)
+	dir, err = GetParentDir(testWindowsAbsPathA)
+	asst.Nil(err, "test GetParentDir() failed")
+	t.Log(dir)
+	dir, err = GetParentDir(testWindowsAbsPathB)
+	asst.Nil(err, "test GetParentDir() failed")
+	t.Log(dir)
+}