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// run -goexperiment fieldtrack
// Copyright 2021 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.
// Test that generics, promoted methods, and //go:nointerface
// interoperate as expected.
package main
import (
"reflect"
)
func TypeString[T any]() string {
return reflect.TypeOf(new(T)).Elem().String()
}
func Test[T, Bad, Good any]() {
switch interface{}(new(T)).(type) {
case Bad:
println("FAIL:", TypeString[T](), "matched", TypeString[Bad]())
case Good:
// ok
default:
println("FAIL:", TypeString[T](), "did not match", TypeString[Good]())
}
}
func TestE[T any]() { Test[T, interface{ EBad() }, interface{ EGood() }]() }
func TestX[T any]() { Test[T, interface{ XBad() }, interface{ XGood() }]() }
type E struct{}
//go:nointerface
func (E) EBad() {}
func (E) EGood() {}
type X[T any] struct{ E }
//go:nointerface
func (X[T]) XBad() {}
func (X[T]) XGood() {}
type W struct{ X[int] }
func main() {
_ = E.EGood
_ = E.EBad
TestE[E]()
_ = X[int].EGood
_ = X[int].EBad
_ = X[int].XGood
_ = X[int].XBad
TestE[X[int]]()
TestX[X[int]]()
_ = W.EGood
_ = W.EBad
_ = W.XGood
_ = W.XBad
TestE[W]()
TestX[W]()
}
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