github.com/bytedance/mockey@v1.2.10/mock_generics.go (about)

     1  /*
     2   * Copyright 2022 ByteDance Inc.
     3   *
     4   * Licensed under the Apache License, Version 2.0 (the "License");
     5   * you may not use this file except in compliance with the License.
     6   * You may obtain a copy of the License at
     7   *
     8   *     http://www.apache.org/licenses/LICENSE-2.0
     9   *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  
    17  package mockey
    18  
    19  import (
    20  	"reflect"
    21  	"unsafe"
    22  )
    23  
    24  // MockGeneric mocks generic function
    25  //
    26  // Target must be generic method or method of generic types
    27  func MockGeneric(target interface{}) *MockBuilder {
    28  	return Mock(target, OptGeneric)
    29  }
    30  
    31  type GenericInfo uintptr
    32  
    33  var genericInfoType = reflect.TypeOf(GenericInfo(0))
    34  
    35  func (g GenericInfo) Equal(other GenericInfo) bool {
    36  	return g == other
    37  }
    38  
    39  // UsedParamType get the type of used parameter in generic function/struct
    40  //
    41  // For example: assume we have generic function "f[int, float64](x int, y T1) T2" and derived type f[int, float64]:
    42  //
    43  //	UsedParamType(0) == reflect.TypeOf(int(0))
    44  //	UsedParamType(1) == reflect.TypeOf(float64(0))
    45  //
    46  // If index n is out of range, or the derived types have more complex structure(for example: define an generic struct
    47  // in a generic function using generic types, unused parameterized type etc.), this function may return unexpected value
    48  // or cause unrecoverable runtime error . So it is NOT RECOMMENDED to use this function unless you actually knows what
    49  // you are doing.
    50  func (g GenericInfo) UsedParamType(n uintptr) reflect.Type {
    51  	var vt interface{}
    52  	*(*uintptr)(unsafe.Pointer(&vt)) = *(*uintptr)(unsafe.Pointer(uintptr(g) + 8*n))
    53  	return reflect.TypeOf(vt)
    54  }