mirror of
https://github.com/golang/go
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54 lines
867 B
Go
54 lines
867 B
Go
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// run
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// Copyright 2017 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// This test makes sure that itabs are unique.
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// More explicitly, we require that only one itab structure exists for the pair of
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// a given compile-time interface type and underlying concrete type.
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// Ensuring this invariant enables fixes for 18492 (improve type switch code).
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package main
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type I interface {
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M()
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}
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type J interface {
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M()
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}
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type T struct{}
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func (*T) M() {}
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func main() {
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test1()
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test2()
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}
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func test1() {
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t := new(T)
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var i1, i2 I
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var j interface {
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M()
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}
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i1 = t
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j = t
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i2 = j
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if i1 != i2 {
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panic("interfaces not equal")
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}
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}
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func test2() {
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t := new(T)
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i1 := (I)(t)
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i2 := (I)((interface {
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M()
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})((J)(t)))
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if i1 != i2 {
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panic("interfaces not equal")
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}
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}
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