Source: export_unsafe.go in package github.com/google/go-cmp/cmp

Source File
	export_unsafe.go

Belonging Package
	github.com/google/go-cmp/cmp

+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()

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


The pages are generated with Golds v0.3.2-preview. (GOOS=darwin GOARCH=amd64)
Golds is a Go 101 project developed by Tapir Liu.
PR and bug reports are welcome and can be submitted to the issue list.
Please follow @Go100and1 (reachable from the left QR code) to get the latest news of Golds.