| 1 | // Copyright 2020 The Go Authors. All rights reserved. |
|---|---|
| 2 | // Use of this source code is governed by a BSD-style |
| 3 | // license that can be found in the LICENSE file. |
| 4 | |
| 5 | // This file contains tests for the ifaceassert checker. |
| 6 | |
| 7 | package a |
| 8 | |
| 9 | import "io" |
| 10 | |
| 11 | func InterfaceAssertionTest() { |
| 12 | var ( |
| 13 | a io.ReadWriteSeeker |
| 14 | b interface { |
| 15 | Read() |
| 16 | Write() |
| 17 | } |
| 18 | ) |
| 19 | _ = a.(io.Reader) |
| 20 | _ = a.(io.ReadWriter) |
| 21 | _ = b.(io.Reader) // want `^impossible type assertion: no type can implement both interface{Read\(\); Write\(\)} and io.Reader \(conflicting types for Read method\)$` |
| 22 | _ = b.(interface { // want `^impossible type assertion: no type can implement both interface{Read\(\); Write\(\)} and interface{Read\(p \[\]byte\) \(n int, err error\)} \(conflicting types for Read method\)$` |
| 23 | Read(p []byte) (n int, err error) |
| 24 | }) |
| 25 | |
| 26 | switch a.(type) { |
| 27 | case io.ReadWriter: |
| 28 | case interface { // want `^impossible type assertion: no type can implement both io.ReadWriteSeeker and interface{Write\(\)} \(conflicting types for Write method\)$` |
| 29 | Write() |
| 30 | }: |
| 31 | default: |
| 32 | } |
| 33 | |
| 34 | switch b := b.(type) { |
| 35 | case io.ReadWriter, interface{ Read() }: // want `^impossible type assertion: no type can implement both interface{Read\(\); Write\(\)} and io.ReadWriter \(conflicting types for Read method\)$` |
| 36 | case io.Writer: // want `^impossible type assertion: no type can implement both interface{Read\(\); Write\(\)} and io.Writer \(conflicting types for Write method\)$` |
| 37 | default: |
| 38 | _ = b |
| 39 | } |
| 40 | } |
| 41 |