PHP :: Doc Bug #71746 :: UTF-8 codepoint escape sequences allow arbitrary number of leading zeros

Doc Bug #71746	UTF-8 codepoint escape sequences allow arbitrary number of leading zeros
Submitted:	2016-03-08 15:43 UTC	Modified:	2018-11-23 09:19 UTC
From:	dragondreamer at live dot com	Assigned:	salathe (profile)
Status:	Closed	Package:	Documentation problem
PHP Version:	7.0.4	OS:
Private report:	No	CVE-ID:	None

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[2016-03-08 15:43 UTC] dragondreamer at live dot com

Description:
------------
PHP documentation specifies the following format of UTF-8 codepoint escape sequences: \u{[0-9a-f]{1,6}}

However, it's currently possible to use them like this:

<?php
echo "\u{0000000000000000000000000000000000000000000000000041}"; //Works

Moreover, it's currently possible to use capital hexadecimal letters despite documentation says, that only lower-case letters are allowed:

<?php
echo "\u{AA}"; //Works

I'm not sure if these are documentation or compiler bugs.

Patches

Pull Requests

History

AllCommentsChangesGit/SVN commitsRelated reports

[2016-03-08 21:12 UTC] yohgaki@php.net

This must be fixed. Recent Unicode does not allow this kind of redundant expressions.

[2016-03-08 21:19 UTC] yohgaki@php.net

However, ES6 seems to have the same spec.

https://mathiasbynens.be/notes/javascript-escapes#unicode-code-point

IMO, this should be fixed as it only introduces complexity for validations.

[2016-03-08 21:25 UTC] ajf@php.net

-Type: Bug +Type: Documentation Problem

[2016-03-08 21:25 UTC] ajf@php.net

This is a documentation bug. It was fully my intention to allow however many leading zeros you like, and whatever capitalisation you like.

[2016-03-08 21:28 UTC] ajf@php.net

Note that the language specification is explicit here, it says "Implementations MUST support leading zeroes", and specifies that hexadecimal digits can be uppercase or lowercase: https://github.com/php/php-langspec/blob/2888f580bd887e6a37e0821beca714843fc095e1/spec/09-lexical-structure.md#double-quoted-string-literals

[2016-04-10 17:41 UTC] temp at temp dot ru

-Package: *Compile Issues +Package: Documentation problem

[2016-04-10 17:41 UTC] temp at temp dot ru

changing package to doc

[2016-04-11 07:59 UTC] salathe@php.net

Automatic comment from SVN on behalf of salathe
Revision: http://svn.php.net/viewvc/?view=revision&amp;revision=338989
Log: unicode escape sequence allows uppercase and any number of digits (doc bug #71746)

[2016-04-11 08:03 UTC] salathe@php.net

-Status: Open +Status: Closed -Assigned To: +Assigned To: salathe

[2016-04-11 08:03 UTC] salathe@php.net

This bug has been fixed in the documentation's XML sources. Since the
online and downloadable versions of the documentation need some time
to get updated, we would like to ask you to be a bit patient.

Thank you for the report, and for helping us make our documentation better.

[2018-11-23 09:19 UTC] dragondreamer at live dot com

-: temp at temp dot ru +: dragondreamer at live dot com

[2018-11-23 09:19 UTC] dragondreamer at live dot com

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