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Source file src/encoding/json/fold_test.go

Documentation: encoding/json

     1  // Copyright 2013 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  package json
     6  
     7  import (
     8  	"bytes"
     9  	"strings"
    10  	"testing"
    11  	"unicode/utf8"
    12  )
    13  
    14  var foldTests = []struct {
    15  	fn   func(s, t []byte) bool
    16  	s, t string
    17  	want bool
    18  }{
    19  	{equalFoldRight, "", "", true},
    20  	{equalFoldRight, "a", "a", true},
    21  	{equalFoldRight, "", "a", false},
    22  	{equalFoldRight, "a", "", false},
    23  	{equalFoldRight, "a", "A", true},
    24  	{equalFoldRight, "AB", "ab", true},
    25  	{equalFoldRight, "AB", "ac", false},
    26  	{equalFoldRight, "sbkKc", "ſbKKc", true},
    27  	{equalFoldRight, "SbKkc", "ſbKKc", true},
    28  	{equalFoldRight, "SbKkc", "ſbKK", false},
    29  	{equalFoldRight, "e", "é", false},
    30  	{equalFoldRight, "s", "S", true},
    31  
    32  	{simpleLetterEqualFold, "", "", true},
    33  	{simpleLetterEqualFold, "abc", "abc", true},
    34  	{simpleLetterEqualFold, "abc", "ABC", true},
    35  	{simpleLetterEqualFold, "abc", "ABCD", false},
    36  	{simpleLetterEqualFold, "abc", "xxx", false},
    37  
    38  	{asciiEqualFold, "a_B", "A_b", true},
    39  	{asciiEqualFold, "aa@", "aa`", false}, // verify 0x40 and 0x60 aren't case-equivalent
    40  }
    41  
    42  func TestFold(t *testing.T) {
    43  	for i, tt := range foldTests {
    44  		if got := tt.fn([]byte(tt.s), []byte(tt.t)); got != tt.want {
    45  			t.Errorf("%d. %q, %q = %v; want %v", i, tt.s, tt.t, got, tt.want)
    46  		}
    47  		truth := strings.EqualFold(tt.s, tt.t)
    48  		if truth != tt.want {
    49  			t.Errorf("strings.EqualFold doesn't agree with case %d", i)
    50  		}
    51  	}
    52  }
    53  
    54  func TestFoldAgainstUnicode(t *testing.T) {
    55  	const bufSize = 5
    56  	buf1 := make([]byte, 0, bufSize)
    57  	buf2 := make([]byte, 0, bufSize)
    58  	var runes []rune
    59  	for i := 0x20; i <= 0x7f; i++ {
    60  		runes = append(runes, rune(i))
    61  	}
    62  	runes = append(runes, kelvin, smallLongEss)
    63  
    64  	funcs := []struct {
    65  		name   string
    66  		fold   func(s, t []byte) bool
    67  		letter bool // must be ASCII letter
    68  		simple bool // must be simple ASCII letter (not 'S' or 'K')
    69  	}{
    70  		{
    71  			name: "equalFoldRight",
    72  			fold: equalFoldRight,
    73  		},
    74  		{
    75  			name:   "asciiEqualFold",
    76  			fold:   asciiEqualFold,
    77  			simple: true,
    78  		},
    79  		{
    80  			name:   "simpleLetterEqualFold",
    81  			fold:   simpleLetterEqualFold,
    82  			simple: true,
    83  			letter: true,
    84  		},
    85  	}
    86  
    87  	for _, ff := range funcs {
    88  		for _, r := range runes {
    89  			if r >= utf8.RuneSelf {
    90  				continue
    91  			}
    92  			if ff.letter && !isASCIILetter(byte(r)) {
    93  				continue
    94  			}
    95  			if ff.simple && (r == 's' || r == 'S' || r == 'k' || r == 'K') {
    96  				continue
    97  			}
    98  			for _, r2 := range runes {
    99  				buf1 := append(buf1[:0], 'x')
   100  				buf2 := append(buf2[:0], 'x')
   101  				buf1 = buf1[:1+utf8.EncodeRune(buf1[1:bufSize], r)]
   102  				buf2 = buf2[:1+utf8.EncodeRune(buf2[1:bufSize], r2)]
   103  				buf1 = append(buf1, 'x')
   104  				buf2 = append(buf2, 'x')
   105  				want := bytes.EqualFold(buf1, buf2)
   106  				if got := ff.fold(buf1, buf2); got != want {
   107  					t.Errorf("%s(%q, %q) = %v; want %v", ff.name, buf1, buf2, got, want)
   108  				}
   109  			}
   110  		}
   111  	}
   112  }
   113  
   114  func isASCIILetter(b byte) bool {
   115  	return ('A' <= b && b <= 'Z') || ('a' <= b && b <= 'z')
   116  }
   117  

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