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正则表达式压缩换行符不转换为PHP

regex php

0

Ben · 技术社区 · 8 年前

我试图降低标记(从HTML生成)并去掉HTML中仅用于格式化的额外换行。我有一个关于正则表达式的工作示例 https://regex101.com/r/dEhyN3/1 但当我把它转换成PHP时,它不起作用,我很难理解为什么。

public function squashEmptyLineBreaks(string $markdown) : string
{
    return preg_replace('/\n{2,}/', '\n\n', $markdown);
}

测试:

    /** @test */
    public function verifySquashEmptyLineBreaks()
    {
        $original = <<<EOF
**Language**

 - Added four languages: Italian, Portuguese (Brazil), Spanish (Mexico) and Chinese (Traditional)





**Bug fixes**


 - Fixed camera jittering for passenger sitting on the back of a motorcycle with sidecar
EOF;
        $expected = <<<EOF
**Language**

 - Added four languages: Italian, Portuguese (Brazil), Spanish (Mexico) and Chinese (Traditional)

**Bug fixes**

 - Fixed camera jittering for passenger sitting on the back of a motorcycle with sidecar
EOF;

        $this->assertEquals($expected, $this->parsesMarkdown->headersNeverAtEndOfLine($original));
    }

此测试继续失败,输出未修改。 我疯了还是忽略了什么?

1 回复 | 直到 8 年前

1

Jirka Hrazdil 8 年前

注意,在单引号字符串中,序列如 \n 未处理。请改用双引号字符串。

public function squashEmptyLineBreaks(string $markdown) : string
{
    return preg_replace("/\n{2,}/", "\n\n", $markdown);
}