Hygiene

The hygiene section decides on code that can be written more simply with the same meaning: an alias instead of the function itself, is_null() and intval() instead of a language construct, dirname(__FILE__) instead of __DIR__, get_class() instead of ::class, call_user_func() instead of a direct call, two calls of isset() or unset() instead of one, and an argument that PHP ignores or that only repeats the default.

A language construct is always fast, and the namespace does not matter for it. Inside a namespace, these fixes are risky fixes: an unqualified is_null() can be the function App\is_null() declared by your project. Until the configuration says nameResolution: certain, they wait for your permission.

A direct call instead of call_user_func() is also risky in a file with strict_types: call_user_func() passes the arguments the way a caller without strict types would, so the direct call can throw a TypeError where the value used to be converted. This does not apply where PHP itself already turns the call into a direct one, that is, for a global function without named or unpacked arguments. A parameter passed by reference brings no risk: PHP already reports a warning for it on every call of call_user_func(), so the only code that changes is code that already does not work cleanly.

hygiene:
	aliasFunctions: [core]
	conversionFunction: forbidden
	is_null: forbidden
	dirnameOfFile: forbidden
	classNameNotation:
		object: required
	call_user_func: forbidden

$count = sizeof($items);  // The alias `sizeof()` must be written `count()`.
$id = intval($row['id']);  // The `intval()` call must be written as the `(int)` cast.
if (is_null($user)) {  // The `is_null()` call must be written as a comparison with `null`.
	$dir = dirname(__FILE__);  // The `dirname(__FILE__)` call must be written `__DIR__`.
}
$type = get_class($order);  // The class name must be obtained with `$order::class`.
$result = call_user_func($callback, $id);  // The callable must be called directly, not through `call_user_func()`.

$count = count($items);
$id = (int) $row['id'];
if ($user === null) {
	$dir = __DIR__;
}
$type = $order::class;
$result = $callback($id);

The section and the set cleanup are not the same thing: the set also makes decisions in other sections, such as unused imports or empty comments, and it takes only part of this section. In --only, fixRisky or severity, you write the section as hygiene and the set as cleanup. Only the section and the set types share a name, so where a bare types could mean either, DressCode rejects it: you write the section as types.* and the set as types.

hygiene.classNameNotation.currentClass

self::class, static::class and parent::class for get_class(), get_called_class(), get_parent_class() and __CLASS__.

• required: always there
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette required, symfony keep, laravel keep · covers SlevomatCodingStandard.Classes.ModernClassNameReference

hygiene.classNameNotation.object

$object::class for get_class($object).

• required: always there
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette required, symfony keep, laravel keep · covers get_class_to_class_keyword, SlevomatCodingStandard.Classes.ModernClassNameReference

hygiene.repeatedCatchBody

Two adjacent catches of one body, written as one catch (A|B $e).

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · PHP 7.1 · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep

hygiene.unreadCatchVariable

The variable of a catch that is never read, catch (E) written instead.

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · PHP 8.0 · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep · covers SlevomatCodingStandard.Exceptions.RequireNonCapturingCatch

hygiene.aliasFunctions

The sets of functions whose aliases are written by their canonical names.

• a list of these words:
  • all: every set below
  • core: the core functions, sizeof() is count(), join() is implode()
  • imap: imap_*
  • ldap: ldap_*
  • mysqli: mysqli_*
  • pg: pg_exec() is pg_query()
  • oci: oci_*
  • odbc: odbc_*
  • openssl: openssl_*
  • sodium: sodium_*
  • ftp: ftp_quit() is ftp_close()
  • posix: posix_errno() is posix_get_last_error()
  • pcntl: pcntl_errno() is pcntl_get_last_error()
  • time: mktime() and gmmktime() without arguments are time()
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette [core, imap, pg], symfony keep, laravel [core, imap, pg] · covers no_alias_functions

hygiene.call_user_func

call_user_func($f, $x) is $f($x), call_user_func_array($f, $a) is $f(...$a).

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · PHP 7.0 · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep · covers regular_callable_call

hygiene.call_user_funcMethods

Whether a method the callable names as [$this, 'run'], [self::class, 'make'] or 'Acme\Shop\Order::make' is called directly too.

• yes or no

Default no · PHP 7.0 · standards: perCs no, psr12 no, nette no, symfony no, laravel no

hygiene.conversionFunction

intval($x) is (int) $x; intval($x, 16) is no cast.

Not about which name of floatval() the code writes, doubleval() being an alias hygiene.aliasFunctions renames too.

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep · covers modernize_types_casting

hygiene.dirnameOfFile

dirname(__FILE__), which is __DIR__.

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep · covers PhpCsFixerCustomFixers/no_useless_dirname_call, combine_nested_dirname, dir_constant

hygiene.nestedDirname

A dirname() of a dirname(), which is one call with the levels argument.

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep

hygiene.__invokeCall

$f->__invoke($x) is $f($x).

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep · covers SlevomatCodingStandard.PHP.DisallowDirectMagicInvokeCall

hygiene.is_null

is_null($x) is $x === null.

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep · covers is_null

hygiene.strlenEmptyTest

strlen($s) === 0 is $s === ''.

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · needs types · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep · covers PhpCsFixerCustomFixers/no_useless_strlen, string_length_to_empty

hygiene.settype

settype($x, 'int') as a statement is $x = (int) $x.

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep · covers set_type_to_cast

hygiene.defaultArgument

An argument PHP ignores or that repeats the default.

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep

An argument that only repeats the default is always removed from a function call. For a method, a static method and new, DressCode needs the types of the code: it must know every class the receiver can be, and each of them must declare the same default. It ignores a child class that might change the default, because such a class would break the contract of its type. A receiver of an unknown type, or one that can be several classes with different defaults, stays as it is, and without types, methods and new stay as they are everywhere.

typeAnalysis: phpstan

hygiene:
	defaultArgument: forbidden

$json = json_encode($data, 0);  // Useless `flags` argument of `json_encode()`, because it repeats the default value.
$memcached->delete($key, 0);  // Useless `time` argument of `Memcached::delete()`, because it repeats the default value.

$json = json_encode($data);
$memcached->delete($key);

hygiene.separateIssets

isset($a) && isset($b) is isset($a, $b).

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep · covers combine_consecutive_issets

hygiene.separateUnsets

unset($a); unset($b); is unset($a, $b);.

• forbidden: never there
• keep: nothing is enforced, the code stays as it is

Default keep · standards: perCs keep, psr12 keep, nette forbidden, symfony keep, laravel keep · covers combine_consecutive_unsets