perl - 当我使用 JSON::decode_json 时，Test::Deep::cmp_deeply 中 unicode 字符串的比较失败

Question

在 Perl v5.10.1 中，我需要将带有 unicode 字符的 native Perl 结构与 JSON::decode_json 创建的类似结构进行比较。

示例:

use strict; use warnings;
#use utf8;
use JSON;
use Test::Deep qw(cmp_deeply);
cmp_deeply(["1"], JSON::decode_json('["1"]'), 'utf8 test 11'); # will pass
cmp_deeply(["≥"], JSON::decode_json('["1"]'), 'utf8 test ≥1'); # will fail
cmp_deeply(["1"], JSON::decode_json('["≥"]'), 'utf8 test 1≥'); # will fail
cmp_deeply(["≥"], JSON::decode_json('["≥"]'), 'utf8 test ≥≥'); # should pass

我无法解释最后一个案例发生了什么，为什么这两个结构不相等？我尝试过了 R T F M这并没有真正提高我对这个问题的理解。

这是输出(由于 TAP 太冗长而稍作编辑):

ok 1 - utf8 test 11
not ok 2 - utf8 test ≥1
# Compared $data->[0]
#    got : '≥'
# expect : '1'
not ok 3 - utf8 test 1≥
Wide character in print at Test/Builder.pm line 1698.
# Compared $data->[0]
#    got : '1'
# expect : '≥'
not ok 4 - utf8 test ≥≥
Wide character in print at Test/Builder.pm line 1698.
# Compared $data->[0]
#    got : 'â¥'
# expect : '≥'

<小时/>

当我使用 use utf8; 尝试时，情况更糟(脚本在第二次测试后死亡):

ok 1 - utf8 test 11
not ok 2 - utf8 test ≥1
Wide character in print at Test/Builder.pm line 1698.
Wide character in print at Test/Builder.pm line 1698.
Wide character in print at Test/Builder.pm line 1698.
# Compared $data->[0]
#    got : '≥'
# expect : '1'
Wide character in subroutine entry at ...
# Tests were run but no plan was declared and done_testing() was not seen.

我还尝试了一种适用于比较的解决方法..

use utf8;
cmp_deeply(["≥"], JSON->new->utf8(0)->decode('["≥"]'), 'utf8 test ≥≥');

...但我仍然收到愚蠢的警告:

ok 1 - utf8 test ≥≥
Wide character in print at Test/Builder.pm line 1698.

有没有办法让它工作 - 比如 use magic_unicode_solution;？

或者也许我应该以不同的方式进行测试以使其与 Unicode 兼容？

Answer 1

此测试将通过:

use Encode;
cmp_deeply( [ Encode::decode("utf8","≥") ],
    JSON::decode_json('["≥"]'), 'utf8 test ≥≥');

JSON 解码器将输入视为 UTF-8 编码并返回解码后的字符串。您的原始测试(测试 4)将 UTF-8 编码的字符串(两个八位字节)与解码的字符串(单个宽字符)进行比较。