github.com/code-reading/golang@v0.0.0-20220303082512-ba5bc0e589a3/go/src/net/dnsname_test.go (about)

     1  // Copyright 2009 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  //go:build !js
     6  // +build !js
     7  
     8  package net
     9  
    10  import (
    11  	"strings"
    12  	"testing"
    13  )
    14  
    15  type dnsNameTest struct {
    16  	name   string
    17  	result bool
    18  }
    19  
    20  var dnsNameTests = []dnsNameTest{
    21  	// RFC 2181, section 11.
    22  	{"_xmpp-server._tcp.google.com", true},
    23  	{"foo.com", true},
    24  	{"1foo.com", true},
    25  	{"26.0.0.73.com", true},
    26  	{"10-0-0-1", true},
    27  	{"fo-o.com", true},
    28  	{"fo1o.com", true},
    29  	{"foo1.com", true},
    30  	{"a.b..com", false},
    31  	{"a.b-.com", false},
    32  	{"a.b.com-", false},
    33  	{"a.b..", false},
    34  	{"b.com.", true},
    35  }
    36  
    37  func emitDNSNameTest(ch chan<- dnsNameTest) {
    38  	defer close(ch)
    39  	var char63 = ""
    40  	for i := 0; i < 63; i++ {
    41  		char63 += "a"
    42  	}
    43  	char64 := char63 + "a"
    44  	longDomain := strings.Repeat(char63+".", 5) + "example"
    45  
    46  	for _, tc := range dnsNameTests {
    47  		ch <- tc
    48  	}
    49  
    50  	ch <- dnsNameTest{char63 + ".com", true}
    51  	ch <- dnsNameTest{char64 + ".com", false}
    52  
    53  	// Remember: wire format is two octets longer than presentation
    54  	// (length octets for the first and [root] last labels).
    55  	// 253 is fine:
    56  	ch <- dnsNameTest{longDomain[len(longDomain)-253:], true}
    57  	// A terminal dot doesn't contribute to length:
    58  	ch <- dnsNameTest{longDomain[len(longDomain)-253:] + ".", true}
    59  	// 254 is bad:
    60  	ch <- dnsNameTest{longDomain[len(longDomain)-254:], false}
    61  }
    62  
    63  func TestDNSName(t *testing.T) {
    64  	ch := make(chan dnsNameTest)
    65  	go emitDNSNameTest(ch)
    66  	for tc := range ch {
    67  		if isDomainName(tc.name) != tc.result {
    68  			t.Errorf("isDomainName(%q) = %v; want %v", tc.name, !tc.result, tc.result)
    69  		}
    70  	}
    71  }
    72  
    73  func BenchmarkDNSName(b *testing.B) {
    74  	testHookUninstaller.Do(uninstallTestHooks)
    75  
    76  	benchmarks := append(dnsNameTests, []dnsNameTest{
    77  		{strings.Repeat("a", 63), true},
    78  		{strings.Repeat("a", 64), false},
    79  	}...)
    80  	for n := 0; n < b.N; n++ {
    81  		for _, tc := range benchmarks {
    82  			if isDomainName(tc.name) != tc.result {
    83  				b.Errorf("isDomainName(%q) = %v; want %v", tc.name, !tc.result, tc.result)
    84  			}
    85  		}
    86  	}
    87  }