Hi Nikita

Yes that would be nice, if it's not too much of a hassle. I'm only able to test 
this in one or two large Laravel projects, so it would still be a limited test.

Kind regards
Brent

> On 15 Jul 2020, at 10:53, Nikita Popov <nikita....@gmail.com> wrote:
> 
> On Wed, Jul 15, 2020 at 10:49 AM Brent Roose <bre...@stitcher.io 
> <mailto:bre...@stitcher.io>> wrote:
> Hi Nikita
> 
> Is the ini setting available in current 7.4 builds? Is it documented 
> somewhere? I'd like to test this change in some of our projects.
> 
> We did not introduce an ini setting in PHP 7.4, I only used it for my own 
> experiments. The implementation is available at 
> https://github.com/php/php-src/pull/3917 
> <https://github.com/php/php-src/pull/3917>. I could rebase that to current 
> 7.4 if that would be useful.
> 
> Nikita
>> On 15 Jul 2020, at 10:28, Nikita Popov <nikita....@gmail.com 
>> <mailto:nikita....@gmail.com>> wrote:
>> 
>> On Tue, Jul 14, 2020 at 11:47 PM Björn Larsson <bjorn.x.lars...@telia.com 
>> <mailto:bjorn.x.lars...@telia.com>>
>> wrote:
>> 
>>> Den 2020-07-14 kl. 15:48, skrev Nikita Popov:
>>>> On Thu, Jul 2, 2020 at 10:09 AM Nikita Popov <nikita....@gmail.com 
>>>> <mailto:nikita....@gmail.com>>
>>> wrote:
>>>> 
>>>>> On Mon, Mar 4, 2019 at 6:00 PM Nikita Popov <nikita....@gmail.com 
>>>>> <mailto:nikita....@gmail.com>>
>>> wrote:
>>>>> 
>>>>>> On Wed, Feb 27, 2019 at 10:23 AM Zeev Suraski <z...@php.net 
>>>>>> <mailto:z...@php.net>> wrote:
>>>>>> 
>>>>>>> 
>>>>>>> On Tue, Feb 26, 2019 at 2:27 PM Nikita Popov <nikita....@gmail.com 
>>>>>>> <mailto:nikita....@gmail.com>>
>>>>>>> wrote:
>>>>>>> 
>>>>>>>> Hi internals,
>>>>>>>> 
>>>>>>>> I think it is well known that == in PHP is a pretty big footgun. It
>>>>>>>> doesn't
>>>>>>>> have to be. I think that type juggling comparisons in a language like
>>>>>>>> PHP
>>>>>>>> have some merit, it's just that the particular semantics of == in PHP
>>>>>>>> make
>>>>>>>> it so dangerous. The biggest WTF factor is probably that 0 ==
>>> "foobar"
>>>>>>>> returns true.
>>>>>>>> 
>>>>>>>> I'd like to bring forward an RFC for PHP 8 to change the semantics
>>> of ==
>>>>>>>> and other non-strict comparisons, when used between a number and a
>>>>>>>> string:
>>>>>>>> 
>>>>>>>> https://wiki.php.net/rfc/string_to_number_comparison 
>>>>>>>> <https://wiki.php.net/rfc/string_to_number_comparison>
>>>>>>>> 
>>>>>>>> The tl;dr is that if you compare a number and a numeric string,
>>> they'll
>>>>>>>> be
>>>>>>>> compared as numbers. Otherwise, the number is converted into a string
>>>>>>>> and
>>>>>>>> they'll be compared as strings.
>>>>>>>> 
>>>>>>>> This is a very significant change -- not so much because the actual
>>> BC
>>>>>>>> breakage is expected to be particularly large, but because it is a
>>>>>>>> silent
>>>>>>>> change in core language semantics, which makes it hard to determine
>>>>>>>> whether
>>>>>>>> or not code is affected by the change. There are things we can do
>>> about
>>>>>>>> this, for example the RFC suggests that we might want to have a
>>>>>>>> transition
>>>>>>>> mode where we perform the comparison using both the old and the new
>>>>>>>> semantics and warn if the result differs.
>>>>>>>> 
>>>>>>>> I think we should give serious consideration to making such a change.
>>>>>>>> I'd
>>>>>>>> be interested to hear whether other people think this is worthwhile,
>>> and
>>>>>>>> how we could go about doing it, while minimizing breakage.
>>>>>>>> 
>>>>>>> I generally like the direction and think we should seriously consider
>>> it.
>>>>>>> 
>>>>>>> I think that before we make any decisions on this, or even dive too
>>> deep
>>>>>>> into the discussion - we actually need to implement this behavior,
>>>>>>> including the proposed INI setting you mentioned we might add in 7.4
>>> - and
>>>>>>> see what happens in some real world apps, at least in terms of
>>> potential
>>>>>>> danger (as you say, figuring out whether there's actual breakage would
>>>>>>> require a full audit of every potentially problematic sample.
>>> Ultimately,
>>>>>>> I think there's no question that if we were to start from scratch,
>>> we'd be
>>>>>>> going for something along these lines.  But since we're not starting
>>> from
>>>>>>> scratch - scoping the level of breakage is key here.
>>>>>>> 
>>>>>>> Zeev
>>>>>>> 
>>>>>> Totally agree that assessing the amount of breakage in real code is key
>>>>>> here. I have now implemented a warning for PHP 7.4 (for now
>>> unconditional,
>>>>>> no ini setting) that is thrown whenever the result of a comparison is
>>> going
>>>>>> to change under the currently proposed rules:
>>>>>> https://github.com/php/php-src/pull/3917 
>>>>>> <https://github.com/php/php-src/pull/3917>
>>>>>> 
>>>>>> I've done a few initial tests by running this against the Laravel,
>>>>>> Symfony and pear-core. The warning was thrown 2 times for Laravel, 1
>>> times
>>>>>> for Symfony and 2 times for pear-core. (See PR for the results.)
>>>>>> 
>>>>>> Both of the warnings in pear-core pointed to implementation bugs. The
>>>>>> Symfony warning was due to trailing whitespace not being allowed in
>>> numeric
>>>>>> strings (something we should definitely change). One of the Laravel
>>>>>> warnings is ultimately a false-positive (does not change behavior),
>>> though
>>>>>> code could be improved to avoid it. I wasn't able to tell whether the
>>> other
>>>>>> one is problematic, as it affects sorting order.
>>>>>> 
>>>>>> I have to say that this is a lot less warnings than I expected. Makes
>>> me
>>>>>> wonder if I didn't make an implementation mistake ^^
>>>>>> 
>>>>>> Regards,
>>>>>> Nikita
>>>>>> 
>>>>> As we're moving closer to PHP 8 feature freeze, I want to give this RFC
>>> a
>>>>> bump. I've updated the text to account for some changes that have
>>> happened
>>>>> in the meantime, such as the removal of locale-sensitivity for float to
>>>>> string conversions.
>>>>> 
>>>>> It's been quite a while since we discussed this last, and back then the
>>>>> discussion was fairly positive. Some experiments with a warning mode
>>> also
>>>>> showed that the impact, at least in framework/library code, appears to
>>> be
>>>>> fairly low in practice, contrary to what one might intuitively expect.
>>>>> 
>>>>> Now would be the time to decide whether or not we want to pursue this
>>>>> change for PHP 8.
>>>>> 
>>>> And then there was silence...
>>>> 
>>>> I think I'll just put this up for vote on Friday, and we'll see what
>>> people
>>>> think :)
>>>> 
>>>> Nikita
>>> 
>>> Seems like a very good idea!! Especially in conjunction with the RFC:
>>> - https://wiki.php.net/rfc/saner-numeric-strings 
>>> <https://wiki.php.net/rfc/saner-numeric-strings>
>>> 
>>> Btw, in the RFC there is a reference to the "Trailing whitespace in numeric
>>> strings" RFC. Update to reference "Saner numeric strings" RFC instead?
>>> 
>> 
>> Thanks, I've updated the link to point to the new proposal!
>> 
>> Nikita
> 

Reply via email to