75 lines
2.1 KiB
Go
75 lines
2.1 KiB
Go
// Copyright 2019 Google Inc. All rights reserved.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package proptools
|
|
|
|
import (
|
|
"fmt"
|
|
"reflect"
|
|
"strings"
|
|
)
|
|
|
|
// HasTag returns true if a StructField has a tag in the form `name:"foo,value"`.
|
|
func HasTag(field reflect.StructField, name, value string) bool {
|
|
tag := field.Tag.Get(name)
|
|
for len(tag) > 0 {
|
|
idx := strings.Index(tag, ",")
|
|
|
|
if idx < 0 {
|
|
return tag == value
|
|
}
|
|
if tag[:idx] == value {
|
|
return true
|
|
}
|
|
|
|
tag = tag[idx+1:]
|
|
}
|
|
|
|
return false
|
|
}
|
|
|
|
// PropertyIndexesWithTag returns the indexes of all properties (in the form used by reflect.Value.FieldByIndex) that
|
|
// are tagged with the given key and value, including ones found in embedded structs or pointers to structs.
|
|
func PropertyIndexesWithTag(ps interface{}, key, value string) [][]int {
|
|
t := reflect.TypeOf(ps)
|
|
if !isStructPtr(t) {
|
|
panic(fmt.Errorf("type %s is not a pointer to a struct", t))
|
|
}
|
|
t = t.Elem()
|
|
|
|
return propertyIndexesWithTag(t, key, value)
|
|
}
|
|
func propertyIndexesWithTag(t reflect.Type, key, value string) [][]int {
|
|
var indexes [][]int
|
|
|
|
for i := 0; i < t.NumField(); i++ {
|
|
field := t.Field(i)
|
|
ft := field.Type
|
|
if isStruct(ft) || isStructPtr(ft) || isSliceOfStruct(ft) {
|
|
if ft.Kind() == reflect.Ptr || ft.Kind() == reflect.Slice || ft.Kind() == reflect.Map {
|
|
ft = ft.Elem()
|
|
}
|
|
subIndexes := propertyIndexesWithTag(ft, key, value)
|
|
for _, sub := range subIndexes {
|
|
sub = append([]int{i}, sub...)
|
|
indexes = append(indexes, sub)
|
|
}
|
|
} else if HasTag(field, key, value) {
|
|
indexes = append(indexes, field.Index)
|
|
}
|
|
}
|
|
|
|
return indexes
|
|
}
|