func (p *processor) Register(name string, fn func(*DB)) error {
	return (&callback{processor: p}).Register(name, fn)
}

func (p *processor) Remove(name string) error {
	return (&callback{processor: p}).Remove(name)
}

func (p *processor) Replace(name string, fn func(*DB)) error {
	return (&callback{processor: p}).Replace(name, fn)
}

func (p *processor) compile() (err error) {
	var callbacks []*callback

	if err := DB.Transaction(func(tx *gorm.DB) error {
		return nil
	}); err == nil {
		t.Errorf("should returns error when commit with closed conn, got error %v", err)
	}

	if err := DB.Session(&gorm.Session{PrepareStmt: true}).Transaction(func(tx *gorm.DB) error {
		return nil
	}); err == nil {
		t.Errorf("should returns error when commit with closed conn, got error %v", err)
	}
}

			}
			if got == nil {
				t.Fatalf("UnixSecondSerializer.Value() = nil, want %v", tt.want)
			}
			if gotTime, ok := got.(time.Time); !ok {
				t.Errorf("UnixSecondSerializer.Value() returned %T, expected time.Time", got)
			} else if !tt.want.(time.Time).Equal(gotTime) {
				t.Errorf("UnixSecondSerializer.Value() = %v, want %v", got, tt.want)
			}
		})
	}

	if info.Free > info.Total {
		return info, fmt.Errorf("detected free space (%d) > total drive space (%d), fs corruption at (%s). please run 'fsck'", info.Free, info.Total, path)
	}
	info.Used = info.Total - info.Free
	return info, nil
}

// GetDriveStats returns IO stats of the drive by its major:minor
func GetDriveStats(major, minor uint32) (iostats IOStats, err error) {
	return IOStats{}, errors.New("operation unsupported")

				schema.err = fmt.Errorf("failed to parse %s as default value for uint, got error: %v", field.DefaultValue, err)
			}
		}
	case reflect.Float32, reflect.Float64:
		field.DataType = Float
		if field.HasDefaultValue && !skipParseDefaultValue {
			if field.DefaultValueInterface, err = strconv.ParseFloat(field.DefaultValue, 64); err != nil {

	if info.Free > info.Total {
		return info, fmt.Errorf("detected free space (%d) > total drive space (%d), fs corruption at (%s). please run 'fsck'", info.Free, info.Total, path)
	}
	info.Used = info.Total - info.Free
	return info, nil
}

// GetDriveStats returns IO stats of the drive by its major:minor
func GetDriveStats(major, minor uint32) (iostats IOStats, err error) {
	return IOStats{}, errors.New("operation unsupported")

			if testCase.expectedErr {
				t.Log(err)
			}
			if err != nil && !testCase.expectedErr {
				t.Errorf("Expected success, but found %s", err)
			}
			if err == nil && testCase.expectedErr {
				t.Error("Expected error, but got `nil`")
			}
			if update != testCase.expectedUpdate {
				t.Errorf("Expected %t, got %t", testCase.expectedUpdate, update)
			}
		})
	}

		Ffree:  s.Ffree,
		FSType: getFSType(s.Type),
	}
	// Check for overflows.
	// https://github.com/minio/minio/issues/8035
	// XFS can show wrong values at times error out
	// in such scenarios.
	if info.Free > info.Total {
		return info, fmt.Errorf("detected free space (%d) > total drive space (%d), fs corruption at (%s). please run 'fsck'", info.Free, info.Total, path)
	}
	info.Used = info.Total - info.Free
	return info, nil
}

	expected := true
	if locked != expected {
		t.Errorf("TestSimpleWriteLockAcquired(): \nexpected %#v\ngot      %#v", expected, locked)
	}
}

func TestSimpleWriteLockTimedOut(t *testing.T) {
	locked := testSimpleWriteLock(t, testDrwMutexAcquireTimeout)

	expected := false
	if locked != expected {
		t.Errorf("TestSimpleWriteLockTimedOut(): \nexpected %#v\ngot      %#v", expected, locked)
	}
}

		resExpected string
		errExpected error
	}{
		{"abcd", 1, 1, "a", nil},
		{"abcd", -1, 1, "a", nil},
		{"abcd", 999, 999, "", nil},
		{"", 999, 999, "", nil},
		{"测试abc", 1, 1, "测", nil},
		{"测试abc", 5, 5, "c", nil},
	}

	for i, tc := range evalCases {
		res, err := evalSQLSubstring(tc.s, tc.startIdx, tc.length)
		if res != tc.resExpected || err != tc.errExpected {
			t.Errorf("Eval Case %d failed: %v %v", i, res, err)
		}