1 // errorcheck 2 3 // Copyright 2011 The Go Authors. All rights reserved. 4 // Use of this source code is governed by a BSD-style 5 // license that can be found in the LICENSE file. 6 7 // Verify that erroneous switch statements are detected by the compiler. 8 // Does not compile. 9 10 package main 11 12 type I interface { 13 M() 14 } 15 16 func bad() { 17 var i I 18 var s string 19 20 switch i { 21 case s: // ERROR "mismatched types string and I|incompatible types" 22 } 23 24 switch s { 25 case i: // ERROR "mismatched types I and string|incompatible types" 26 } 27 28 var m, m1 map[int]int 29 switch m { 30 case nil: 31 case m1: // ERROR "can only compare map m to nil|map can only be compared to nil" 32 default: 33 } 34 35 var a, a1 []int 36 switch a { 37 case nil: 38 case a1: // ERROR "can only compare slice a to nil|slice can only be compared to nil" 39 default: 40 } 41 42 var f, f1 func() 43 switch f { 44 case nil: 45 case f1: // ERROR "can only compare func f to nil|func can only be compared to nil" 46 default: 47 } 48 49 var ar, ar1 [4]func() 50 switch ar { // ERROR "cannot switch on" 51 case ar1: 52 default: 53 } 54 55 var st, st1 struct{ f func() } 56 switch st { // ERROR "cannot switch on" 57 case st1: 58 } 59 } 60 61 func good() { 62 var i interface{} 63 var s string 64 65 switch i { 66 case s: 67 } 68 69 switch s { 70 case i: 71 } 72 } 73
