diff options
Diffstat (limited to 'vendor/github.com/google/go-cmp/cmp/export_unsafe.go')
-rw-r--r-- | vendor/github.com/google/go-cmp/cmp/export_unsafe.go | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/vendor/github.com/google/go-cmp/cmp/export_unsafe.go b/vendor/github.com/google/go-cmp/cmp/export_unsafe.go new file mode 100644 index 000000000..e2c0f74e8 --- /dev/null +++ b/vendor/github.com/google/go-cmp/cmp/export_unsafe.go @@ -0,0 +1,36 @@ +// Copyright 2017, The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +//go:build !purego +// +build !purego + +package cmp + +import ( + "reflect" + "unsafe" +) + +const supportExporters = true + +// retrieveUnexportedField uses unsafe to forcibly retrieve any field from +// a struct such that the value has read-write permissions. +// +// The parent struct, v, must be addressable, while f must be a StructField +// describing the field to retrieve. If addr is false, +// then the returned value will be shallowed copied to be non-addressable. +func retrieveUnexportedField(v reflect.Value, f reflect.StructField, addr bool) reflect.Value { + ve := reflect.NewAt(f.Type, unsafe.Pointer(uintptr(unsafe.Pointer(v.UnsafeAddr()))+f.Offset)).Elem() + if !addr { + // A field is addressable if and only if the struct is addressable. + // If the original parent value was not addressable, shallow copy the + // value to make it non-addressable to avoid leaking an implementation + // detail of how forcibly exporting a field works. + if ve.Kind() == reflect.Interface && ve.IsNil() { + return reflect.Zero(f.Type) + } + return reflect.ValueOf(ve.Interface()).Convert(f.Type) + } + return ve +} |