mirror of
https://github.com/golang/go
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65 lines
1.2 KiB
Go
65 lines
1.2 KiB
Go
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// run
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// Copyright 2018 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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// Check all ways to compare a non-constant string to the empty string.
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package main
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import (
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"fmt"
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"os"
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)
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var (
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s = "abc"
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e = ""
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failed bool
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)
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func main() {
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want(true, "" < s, `"" < s`)
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want(false, s < "", `s < ""`)
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want(false, "" < e, `"" < e`)
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want(false, e < "", `e < ""`)
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want(true, "" <= s, `"" <= s`)
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want(false, s <= "", `s <= ""`)
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want(true, "" <= e, `"" <= e`)
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want(true, e <= "", `e <= ""`)
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want(false, "" > s, `"" > s`)
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want(true, s > "", `s > ""`)
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want(false, "" > e, `"" > e`)
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want(false, e > "", `e > ""`)
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want(false, "" >= s, `"" >= s`)
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want(true, s >= "", `s >= ""`)
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want(true, "" >= e, `"" >= e`)
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want(true, e >= "", `e >= ""`)
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want(false, "" == s, `"" == s`)
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want(false, s == "", `s == ""`)
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want(true, "" == e, `"" == e`)
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want(true, e == "", `e == ""`)
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want(true, "" != s, `"" != s`)
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want(true, s != "", `s != ""`)
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want(false, "" != e, `"" != e`)
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want(false, e != "", `e != ""`)
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if failed {
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os.Exit(1)
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}
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}
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//go:noinline
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func want(b bool, have bool, msg string) {
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if b != have {
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fmt.Println(msg)
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failed = true
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}
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}
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