mirror of
https://github.com/golang/go
synced 2024-11-02 05:32:33 +00:00
f4f1ba2b1e
The compiler is incorrectly rejecting switches on arrays of comparable types. It also doesn't catch incomparable structs when typechecking the switch, leading to unreadable errors during typechecking of the generated code. Fixes #3894. R=rsc CC=gobot, golang-dev, r, remy https://golang.org/cl/6442074
72 lines
1.2 KiB
Go
72 lines
1.2 KiB
Go
// errorcheck
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// Copyright 2011 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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// Verify that erroneous switch statements are detected by the compiler.
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// Does not compile.
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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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func bad() {
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var i I
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var s string
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switch i {
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case s: // ERROR "mismatched types string and I|incompatible types"
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}
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switch s {
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case i: // ERROR "mismatched types I and string|incompatible types"
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}
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var m, m1 map[int]int
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switch m {
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case nil:
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case m1: // ERROR "can only compare map m to nil|map can only be compared to nil"
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default:
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}
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var a, a1 []int
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switch a {
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case nil:
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case a1: // ERROR "can only compare slice a to nil|slice can only be compared to nil"
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default:
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}
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var f, f1 func()
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switch f {
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case nil:
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case f1: // ERROR "can only compare func f to nil|func can only be compared to nil"
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default:
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}
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var ar, ar1 [4]func()
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switch ar { // ERROR "cannot switch on"
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case ar1:
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default:
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}
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var st, st1 struct{ f func() }
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switch st { // ERROR "cannot switch on"
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case st1:
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}
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}
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func good() {
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var i interface{}
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var s string
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switch i {
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case s:
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}
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switch s {
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case i:
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}
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}
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