github.com/pingcap/tiflow@v0.0.0-20240520035814-5bf52d54e205/dm/pkg/helper/value.go (about)

     1  // Copyright 2019 PingCAP, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package helper
    15  
    16  import "reflect"
    17  
    18  // IsNil tests whether the passed in value is nil.
    19  // ref https://github.com/golang/go/blob/87113f7eadf6d8b12279709f05c0359b54b194ea/src/reflect/value.go#L1049.
    20  func IsNil(vi interface{}) (result bool) {
    21  	if vi == nil {
    22  		result = true
    23  	} else {
    24  		switch v := reflect.ValueOf(vi); v.Kind() {
    25  		case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Ptr, reflect.UnsafePointer, reflect.Slice:
    26  			return v.IsNil()
    27  		}
    28  	}
    29  	return
    30  }