feat: Introduce reference_spaces fixer

[greew]

This pull request adds a new PhpCsFixer\Fixer\Whitespace\ReferenceSpacesFixer.

Based on #7303, this code

<?php
$bar = 'a';
$foo =& $bar;

will be changed to

<?php
$bar = 'a';
$foo = & $bar;

with a space between = and &.

This PR adds to possibility to handle the reference operator individually in the following cases:

• assignments
  • by_reference: $foo = &$bar
  • by_assign: $foo =& $bar
  • single_space: $foo = & $bar
  • no_space: $foo =&$bar
• function signatures
  • by_reference: function foo(&$bar) {...
  • single_space: function foo(& $bar) {...
• use arguments
  • by_reference: $foo = function () use (&bar) {...
  • single_space: $foo = function () use (& bar) {...

[greew]

Locally, I get the following error when running tests:

There was 1 failure:

1) PhpCsFixer\Tests\AutoReview\FixerFactoryTest::testFixerWithNoneDefaultPriorityIsTested
Fixers without default priority and without priority tests: "reference_spaces."
Failed asserting that an array is empty.

/app/tests/AutoReview/FixerFactoryTest.php:326

FAILURES!
Tests: 486, Assertions: 3918, Failures: 1.

I don't know if I should add the reference_spaces anywhere like FixerFactoryTest::getFixersPriorityGraph() or something like that?

[keradus]

what 287 stands for?
(hint: numeric value of token ID may very across different PHP versions)

use T_... constant here instead

[keradus]

the failing test that you see is because you put a non-zero priority here. it is asking you to create an explicit priority testing case in tests/Fixtures/Integration/priority/ , and entry in getFixersPriorityGraph you mentioned

[keradus]

for each of the option here - is any formatting of those preferred by PSR/PER ?

if so, is there a community using other possibilities?
if not - please drop those additional options

As PHP CS Fixer, we do not aim to cover each possible variant of style, but only the recommended / most popular ones, as each configuration option increase the maintenance cost and go against the purpose to spread the best recommendations.

[greew]

Both PSR and PER only mention the reference operator in regards to function signature. Nothing in regards to assignment. I would think that we could easily merge the function_signature and anonymous_function_use_block options into one.

After doing some searching I have not been able to find anything else than

• assignment: $foo =& $bar or $foo = &$bar
• signatures: function foo(&$bar)

I just added function signatures based on @Wirone comment in #7303

Would you say I should altogether remove the function_signature and anonymous... options and just handle assign by reference (either =& $bar or = &$bar) in this PR?

[keradus]

before we go into the new fixer, we need to acknowledge that some users will not use new feature, but instead they will use only already existing features, that will lead to confusing style format.

Can I ask you, before we proceed with this new fixer, to first work on bugfix that would prevent existing rules from applying the wrong change?
If yes, please raise that as a separated PR.

I identified those 2 rules that are doing changes, but let's have it discussed here first:
#7303 (comment)

case 1:

   1) x.php (unary_operator_spaces)
 <?php
 
-$a =& $b;
+$a =&$b;

case 2:

   1) x.php (binary_operator_spaces)
 <?php
 
-$a =& $b;
+$a = & $b;

[coveralls]

coverage: 94.616% (+0.01%) from 94.603% when pulling 184d918 on greew:add-reference-spaces-fixer into 25da939 on PHP-CS-Fixer:master.

[keradus]

this part is already covered by unary_operator_spaces rule.
Why introduce another rule doing the same? We shall avoid this.

[greew]

I'll close this PR as #7388 fixes the issue.

[Wirone]

Sorry if I wasted your time with wrong suggestion, @greew 🙁.

[greew]

I was disappointed, but it was good practice learning more about PHP-CS-Fixer internals 😊