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Doc Bug #71892 substr: returns false if len === start, not just len < start
Submitted: 2016-03-24 17:24 UTC Modified: 2016-04-03 04:22 UTC
From: fredemmott@php.net Assigned:
Status: No Feedback Package: Strings related
PHP Version: 7.0.5RC1 OS: n/a
Private report: No CVE-ID: None
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 [2016-03-24 17:24 UTC] fredemmott@php.net 
Description:
------------
"If string is less than start characters long, FALSE will be returned." - 'less than' should be 'less than or equal to'

Test script:
---------------
<?php

var_dump(substr('a', 0, 2)); // string(1) "a"
var_dump(substr('', 0, 2)); // bool(false)
var_dump(substr('a', 1)); // bool(false)

Expected result:
----------------
Based on the documentation, string(1) "a", string(0) "", string(0) ""

Actual result:
--------------
string(1) "a"
bool(false)
bool(false)

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AllCommentsChangesGit/SVN commitsRelated reports
 [2016-03-24 17:26 UTC] fredemmott@php.net 
The documentation does explicitly describe the empty string as a special case, however it isn't, given the last example, which is not documented.
 [2016-03-25 01:21 UTC] requinix@php.net
-Status: Open +Status: Feedback -Package: Documentation problem +Package: Strings related
 [2016-03-25 01:21 UTC] requinix@php.net 
Sure you're testing with PHP 7? https://3v4l.org/lNZ3N
 [2016-03-25 21:43 UTC] bwoebi@php.net 
Note the changelog section:

7.0.0	If string is equal to start characters long, an empty string will be returned. Prior to this version, FALSE was returned in this case.
 [2016-04-03 04:22 UTC] php-bugs at lists dot php dot net 
No feedback was provided. The bug is being suspended because
we assume that you are no longer experiencing the problem.
If this is not the case and you are able to provide the
information that was requested earlier, please do so and
change the status of the bug back to "Re-Opened". Thank you.
 
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