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List of Available Rules

Alias

• array_push (risky)

  Converts simple usages of array_push($x, $y); to $x[] = $y;.

• backtick_to_shell_exec

  Converts backtick operators to shell_exec calls.

• ereg_to_preg (risky)

  Replace deprecated ereg regular expression functions with preg.

• mb_str_functions (risky)

  Replace non multibyte-safe functions with corresponding mb function.

• modernize_strpos (risky)

  Replace strpos() and stripos() calls with str_starts_with() or str_contains() if possible.

• no_alias_functions (risky)

  Master functions shall be used instead of aliases.

• no_alias_language_construct_call

  Master language constructs shall be used instead of aliases.

• no_mixed_echo_print

  Either language construct print or echo should be used.

• pow_to_exponentiation (risky)

  Converts pow to the ** operator.

• random_api_migration (risky)

  Replaces rand, srand, getrandmax functions calls with their mt_* analogs or random_int.

• set_type_to_cast (risky)

  Cast shall be used, not settype.

Array Notation

• array_syntax

  PHP arrays should be declared using the configured syntax.

• no_multiline_whitespace_around_double_arrow

  Operator => should not be surrounded by multi-line whitespaces.

• no_trailing_comma_in_singleline_array (deprecated)

  PHP single-line arrays should not have trailing comma.

• no_whitespace_before_comma_in_array

  In array declaration, there MUST NOT be a whitespace before each comma.

• normalize_index_brace

  Array index should always be written by using square braces.

• return_to_yield_from

  If the function explicitly returns an array, and has the return type iterable, then yield from must be used instead of return.

• trim_array_spaces

  Arrays should be formatted like function/method arguments, without leading or trailing single line space.

• whitespace_after_comma_in_array

  In array declaration, there MUST be a whitespace after each comma.

• yield_from_array_to_yields (risky)

  Yield from array must be unpacked to series of yields.

Attribute Notation

• attribute_empty_parentheses

  PHP attributes declared without arguments must (not) be followed by empty parentheses.

• general_attribute_remove

  Removes configured attributes by their respective FQN.

• ordered_attributes

  Sorts attributes using the configured sort algorithm.

Basic

• braces (deprecated)

  The body of each structure MUST be enclosed by braces. Braces should be properly placed. Body of braces should be properly indented.

• braces_position

  Braces must be placed as configured.

• curly_braces_position (deprecated)

  Curly braces must be placed as configured.

• encoding

  PHP code MUST use only UTF-8 without BOM (remove BOM).

• no_multiple_statements_per_line

  There must not be more than one statement per line.

• no_trailing_comma_in_singleline

  If a list of values separated by a comma is contained on a single line, then the last item MUST NOT have a trailing comma.

• non_printable_character (risky)

  Remove Zero-width space (ZWSP), Non-breaking space (NBSP) and other invisible unicode symbols.

• numeric_literal_separator

  Adds separators to numeric literals of any kind.

• octal_notation

  Literal octal must be in 0o notation.

• psr_autoloading (risky)

  Classes must be in a path that matches their namespace, be at least one namespace deep and the class name should match the file name.

• single_line_empty_body

  Empty body of class, interface, trait, enum or function must be abbreviated as {} and placed on the same line as the previous symbol, separated by a single space.

Casing

• class_reference_name_casing

  When referencing an internal class it must be written using the correct casing.

• constant_case

  The PHP constants true, false, and null MUST be written using the correct casing.

• integer_literal_case

  Integer literals must be in correct case.

• lowercase_keywords

  PHP keywords MUST be in lower case.

• lowercase_static_reference

  Class static references self, static and parent MUST be in lower case.

• magic_constant_casing

  Magic constants should be referred to using the correct casing.

• magic_method_casing

  Magic method definitions and calls must be using the correct casing.

• native_function_casing

  Function defined by PHP should be called using the correct casing.

• native_function_type_declaration_casing (deprecated)

  Native type declarations for functions should use the correct case.

• native_type_declaration_casing

  Native type declarations should be used in the correct case.

Cast Notation

• cast_spaces

  A single space or none should be between cast and variable.

• lowercase_cast

  Cast should be written in lower case.

• modernize_types_casting (risky)

  Replaces intval, floatval, doubleval, strval and boolval function calls with according type casting operator.

• no_short_bool_cast

  Short cast bool using double exclamation mark should not be used.

• no_unset_cast

  Variables must be set null instead of using (unset) casting.

• short_scalar_cast

  Cast (boolean) and (integer) should be written as (bool) and (int), (double) and (real) as (float), (binary) as (string).

Class Notation

• class_attributes_separation

  Class, trait and interface elements must be separated with one or none blank line.

• class_definition

  Whitespace around the keywords of a class, trait, enum or interfaces definition should be one space.

• final_class (risky)

  All classes must be final, except abstract ones and Doctrine entities.

• final_internal_class (risky)

  Internal classes should be final.

• final_public_method_for_abstract_class (risky)

  All public methods of abstract classes should be final.

• no_blank_lines_after_class_opening

  There should be no empty lines after class opening brace.

• no_null_property_initialization

  Properties MUST not be explicitly initialized with null except when they have a type declaration (PHP 7.4).

• no_php4_constructor (risky)

  Convert PHP4-style constructors to __construct.

• no_unneeded_final_method (risky)

  Removes final from methods where possible.

• ordered_class_elements

  Orders the elements of classes/interfaces/traits/enums.

• ordered_interfaces

  Orders the interfaces in an implements or interface extends clause.

• ordered_traits (risky)

  Trait use statements must be sorted alphabetically.

• ordered_types

  Sort union types and intersection types using configured order.

• phpdoc_readonly_class_comment_to_keyword (risky)

  Converts readonly comment on classes to the readonly keyword.

• protected_to_private

  Converts protected variables and methods to private where possible.

• self_accessor (risky)

  Inside class or interface element self should be preferred to the class name itself.

• self_static_accessor

  Inside an enum or final/anonymous class, self should be preferred over static.

• single_class_element_per_statement

  There MUST NOT be more than one property or constant declared per statement.

• single_trait_insert_per_statement

  Each trait use must be done as single statement.

• static_private_method (risky)

  Converts private methods to static where possible.

• visibility_required

  Classes, constants, properties, and methods MUST have visibility declared, and keyword modifiers MUST be in the following order: inheritance modifier (abstract or final), visibility modifier (public, protected, or private), set-visibility modifier (public(set), protected(set), or private(set)), scope modifier (static), mutation modifier (readonly), type declaration, name.

Class Usage

• date_time_immutable (risky)

  Class DateTimeImmutable should be used instead of DateTime.

Comment

• comment_to_phpdoc (risky)

  Comments with annotation should be docblock when used on structural elements.

• header_comment

  Add, replace or remove header comment.

• multiline_comment_opening_closing

  DocBlocks must start with two asterisks, multiline comments must start with a single asterisk, after the opening slash. Both must end with a single asterisk before the closing slash.

• no_empty_comment

  There should not be any empty comments.

• no_trailing_whitespace_in_comment

  There MUST be no trailing spaces inside comment or PHPDoc.

• single_line_comment_spacing

  Single-line comments must have proper spacing.

• single_line_comment_style

  Single-line comments and multi-line comments with only one line of actual content should use the // syntax.

Constant Notation

• native_constant_invocation (risky)

  Add leading \ before constant invocation of internal constant to speed up resolving. Constant name match is case-sensitive, except for null, false and true.

Control Structure

• control_structure_braces

  The body of each control structure MUST be enclosed within braces.

• control_structure_continuation_position

  Control structure continuation keyword must be on the configured line.

• elseif

  The keyword elseif should be used instead of else if so that all control keywords look like single words.

• empty_loop_body

  Empty loop-body must be in configured style.

• empty_loop_condition

  Empty loop-condition must be in configured style.

• include

  Include/Require and file path should be divided with a single space. File path should not be placed within parentheses.

• no_alternative_syntax

  Replace control structure alternative syntax to use braces.

• no_break_comment

  There must be a comment when fall-through is intentional in a non-empty case body.

• no_superfluous_elseif

  Replaces superfluous elseif with if.

• no_trailing_comma_in_list_call (deprecated)

  Remove trailing commas in list function calls.

• no_unneeded_braces

  Removes unneeded braces that are superfluous and aren’t part of a control structure’s body.

• no_unneeded_control_parentheses

  Removes unneeded parentheses around control statements.

• no_unneeded_curly_braces (deprecated)

  Removes unneeded curly braces that are superfluous and aren’t part of a control structure’s body.

• no_useless_else

  There should not be useless else cases.

• simplified_if_return

  Simplify if control structures that return the boolean result of their condition.

• switch_case_semicolon_to_colon

  A case should be followed by a colon and not a semicolon.

• switch_case_space

  Removes extra spaces between colon and case value.

• switch_continue_to_break

  Switch case must not be ended with continue but with break.

• trailing_comma_in_multiline

  Arguments lists, array destructuring lists, arrays that are multi-line, match-lines and parameters lists must have a trailing comma.

• yoda_style

  Write conditions in Yoda style (true), non-Yoda style (['equal' => false, 'identical' => false, 'less_and_greater' => false]) or ignore those conditions (null) based on configuration.

Doctrine Annotation

• doctrine_annotation_array_assignment

  Doctrine annotations must use configured operator for assignment in arrays.

• doctrine_annotation_braces

  Doctrine annotations without arguments must use the configured syntax.

• doctrine_annotation_indentation

  Doctrine annotations must be indented with four spaces.

• doctrine_annotation_spaces

  Fixes spaces in Doctrine annotations.

Function Notation

• combine_nested_dirname (risky)

  Replace multiple nested calls of dirname by only one call with second $level parameter.

• date_time_create_from_format_call (risky)

  The first argument of DateTime::createFromFormat method must start with !.

• fopen_flag_order (risky)

  Order the flags in fopen calls, b and t must be last.

• fopen_flags (risky)

  The flags in fopen calls must omit t, and b must be omitted or included consistently.

• function_declaration

  Spaces should be properly placed in a function declaration.

• function_typehint_space (deprecated)

  Ensure single space between function’s argument and its typehint.

• implode_call (risky)

  Function implode must be called with 2 arguments in the documented order.

• lambda_not_used_import

  Lambda must not import variables it doesn’t use.

• method_argument_space

  In method arguments and method call, there MUST NOT be a space before each comma and there MUST be one space after each comma. Argument lists MAY be split across multiple lines, where each subsequent line is indented once. When doing so, the first item in the list MUST be on the next line, and there MUST be only one argument per line.

• multiline_promoted_properties (experimental)

  Promoted properties must be on separate lines.

• native_function_invocation (risky)

  Add leading \ before function invocation to speed up resolving.

• no_spaces_after_function_name

  When making a method or function call, there MUST NOT be a space between the method or function name and the opening parenthesis.

• no_trailing_comma_in_singleline_function_call (deprecated)

  When making a method or function call on a single line there MUST NOT be a trailing comma after the last argument.

• no_unreachable_default_argument_value (risky)

  In function arguments there must not be arguments with default values before non-default ones.

• no_useless_sprintf (risky)

  There must be no sprintf calls with only the first argument.

• nullable_type_declaration_for_default_null_value

  Adds or removes ? before single type declarations or |null at the end of union types when parameters have a default null value.

• phpdoc_to_param_type (experimental, risky)

  Takes @param annotations of non-mixed types and adjusts accordingly the function signature.

• phpdoc_to_property_type (experimental, risky)

  Takes @var annotation of non-mixed types and adjusts accordingly the property signature..

• phpdoc_to_return_type (experimental, risky)

  Takes @return annotation of non-mixed types and adjusts accordingly the function signature.

• regular_callable_call (risky)

  Callables must be called without using call_user_func* when possible.

• return_type_declaration

  Adjust spacing around colon in return type declarations and backed enum types.

• single_line_throw

  Throwing exception must be done in single line.

• static_lambda (risky)

  Lambdas not (indirectly) referencing $this must be declared static.

• use_arrow_functions (risky)

  Anonymous functions with return as the only statement must use arrow functions.

• void_return (risky)

  Add void return type to functions with missing or empty return statements, but priority is given to @return annotations.

Import

• fully_qualified_strict_types

  Removes the leading part of fully qualified symbol references if a given symbol is imported or belongs to the current namespace.

• global_namespace_import

  Imports or fully qualifies global classes/functions/constants.

• group_import

  There MUST be group use for the same namespaces.

• no_leading_import_slash

  Remove leading slashes in use clauses.

• no_unneeded_import_alias

  Imports should not be aliased as the same name.

• no_unused_imports

  Unused use statements must be removed.

• ordered_imports

  Ordering use statements.

• single_import_per_statement

  There MUST be one use keyword per declaration.

• single_line_after_imports

  Each namespace use MUST go on its own line and there MUST be one blank line after the use statements block.

Language Construct

• class_keyword (experimental, risky)

  Converts FQCN strings to *::class keywords.

• class_keyword_remove (deprecated)

  Converts ::class keywords to FQCN strings.

• combine_consecutive_issets

  Using isset($var) && multiple times should be done in one call.

• combine_consecutive_unsets

  Calling unset on multiple items should be done in one call.

• declare_equal_normalize

  Equal sign in declare statement should be surrounded by spaces or not following configuration.

• declare_parentheses

  There must not be spaces around declare statement parentheses.

• dir_constant (risky)

  Replaces dirname(__FILE__) expression with equivalent __DIR__ constant.

• error_suppression (risky)

  Error control operator should be added to deprecation notices and/or removed from other cases.

• explicit_indirect_variable

  Add curly braces to indirect variables to make them clear to understand.

• function_to_constant (risky)

  Replace core functions calls returning constants with the constants.

• get_class_to_class_keyword (risky)

  Replace get_class calls on object variables with class keyword syntax.

• is_null (risky)

  Replaces is_null($var) expression with null === $var.

• no_unset_on_property (risky)

  Properties should be set to null instead of using unset.

• nullable_type_declaration

  Nullable single type declaration should be standardised using configured syntax.

• single_space_after_construct (deprecated)

  Ensures a single space after language constructs.

• single_space_around_construct

  Ensures a single space after language constructs.

List Notation

• list_syntax

  List (array destructuring) assignment should be declared using the configured syntax.

Namespace Notation

• blank_line_after_namespace

  There MUST be one blank line after the namespace declaration.

• blank_lines_before_namespace

  Controls blank lines before a namespace declaration.

• clean_namespace

  Namespace must not contain spacing, comments or PHPDoc.

• no_blank_lines_before_namespace (deprecated)

  There should be no blank lines before a namespace declaration.

• no_leading_namespace_whitespace

  The namespace declaration line shouldn’t contain leading whitespace.

• single_blank_line_before_namespace (deprecated)

  There should be exactly one blank line before a namespace declaration.

Naming

• no_homoglyph_names (risky)

  Replace accidental usage of homoglyphs (non ascii characters) in names.

Operator

• assign_null_coalescing_to_coalesce_equal

  Use the null coalescing assignment operator ??= where possible.

• binary_operator_spaces

  Binary operators should be surrounded by space as configured.

• concat_space

  Concatenation should be spaced according to configuration.

• increment_style

  Pre- or post-increment and decrement operators should be used if possible.

• logical_operators (risky)

  Use && and || logical operators instead of and and or.

• long_to_shorthand_operator (risky)

  Shorthand notation for operators should be used if possible.

• new_expression_parentheses

  All new expressions with a further call must (not) be wrapped in parentheses.

• new_with_braces (deprecated)

  All instances created with new keyword must (not) be followed by braces.

• new_with_parentheses

  All instances created with new keyword must (not) be followed by parentheses.

• no_space_around_double_colon

  There must be no space around double colons (also called Scope Resolution Operator or Paamayim Nekudotayim).

• no_useless_concat_operator

  There should not be useless concat operations.

• no_useless_nullsafe_operator

  There should not be useless Null-safe operator ?-> used.

• not_operator_with_space

  Logical NOT operators (!) should have leading and trailing whitespaces.

• not_operator_with_successor_space

  Logical NOT operators (!) should have one trailing whitespace.

• object_operator_without_whitespace

  There should not be space before or after object operators -> and ?->.

• operator_linebreak

  Operators - when multiline - must always be at the beginning or at the end of the line.

• standardize_increment

  Increment and decrement operators should be used if possible.

• standardize_not_equals

  Replace all <> with !=.

• ternary_operator_spaces

  Standardize spaces around ternary operator.

• ternary_to_elvis_operator (risky)

  Use the Elvis operator ?: where possible.

• ternary_to_null_coalescing

  Use null coalescing operator ?? where possible.

• unary_operator_spaces

  Unary operators should be placed adjacent to their operands.

PHP Tag

• blank_line_after_opening_tag

  Ensure there is no code on the same line as the PHP open tag and it is followed by a blank line.

• echo_tag_syntax

  Replaces short-echo <?= with long format <?php echo/<?php print syntax, or vice-versa.

• full_opening_tag

  PHP code must use the long <?php tags or short-echo <?= tags and not other tag variations.

• linebreak_after_opening_tag

  Ensure there is no code on the same line as the PHP open tag.

• no_closing_tag

  The closing ?> tag MUST be omitted from files containing only PHP.

PHPUnit

• php_unit_assert_new_names (risky)

  Rename deprecated PHPUnit assertions like assertFileNotExists to new methods like assertFileDoesNotExist.

• php_unit_attributes

  PHPUnit attributes must be used over their respective PHPDoc-based annotations.

• php_unit_construct (risky)

  PHPUnit assertion method calls like ->assertSame(true, $foo) should be written with dedicated method like ->assertTrue($foo).

• php_unit_data_provider_method_order

  Data provider method must be placed after/before the last/first test where used.

• php_unit_data_provider_name (risky)

  Data provider names must match the name of the test.

• php_unit_data_provider_return_type (risky)

  The return type of PHPUnit data provider must be iterable.

• php_unit_data_provider_static (risky)

  Data providers must be static.

• php_unit_dedicate_assert (risky)

  PHPUnit assertions like assertInternalType, assertFileExists, should be used over assertTrue.

• php_unit_dedicate_assert_internal_type (risky)

  PHPUnit assertions like assertIsArray should be used over assertInternalType.

• php_unit_expectation (risky)

  Usages of ->setExpectedException* methods MUST be replaced by ->expectException* methods.

• php_unit_fqcn_annotation

  PHPUnit annotations should be a FQCNs including a root namespace.

• php_unit_internal_class

  All PHPUnit test classes should be marked as internal.

• php_unit_method_casing

  Enforce camel (or snake) case for PHPUnit test methods, following configuration.

• php_unit_mock (risky)

  Usages of ->getMock and ->getMockWithoutInvokingTheOriginalConstructor methods MUST be replaced by ->createMock or ->createPartialMock methods.

• php_unit_mock_short_will_return (risky)

  Usage of PHPUnit’s mock e.g. ->will($this->returnValue(..)) must be replaced by its shorter equivalent such as ->willReturn(...).

• php_unit_namespaced (risky)

  PHPUnit classes MUST be used in namespaced version, e.g. \PHPUnit\Framework\TestCase instead of \PHPUnit_Framework_TestCase.

• php_unit_no_expectation_annotation (risky)

  Usages of @expectedException* annotations MUST be replaced by ->setExpectedException* methods.

• php_unit_set_up_tear_down_visibility (risky)

  Changes the visibility of the setUp() and tearDown() functions of PHPUnit to protected, to match the PHPUnit TestCase.

• php_unit_size_class

  All PHPUnit test cases should have @small, @medium or @large annotation to enable run time limits.

• php_unit_strict (risky)

  PHPUnit methods like assertSame should be used instead of assertEquals.

• php_unit_test_annotation (risky)

  Adds or removes @test annotations from tests, following configuration.

• php_unit_test_case_static_method_calls (risky)

  Calls to PHPUnit\Framework\TestCase static methods must all be of the same type, either $this->, self:: or static::.

• php_unit_test_class_requires_covers

  Adds a default @coversNothing annotation to PHPUnit test classes that have no @covers* annotation.

PHPDoc

• align_multiline_comment

  Each line of multi-line DocComments must have an asterisk [PSR-5] and must be aligned with the first one.

• general_phpdoc_annotation_remove

  Removes configured annotations from PHPDoc.

• general_phpdoc_tag_rename

  Renames PHPDoc tags.

• no_blank_lines_after_phpdoc

  There should not be blank lines between docblock and the documented element.

• no_empty_phpdoc

  There should not be empty PHPDoc blocks.

• no_superfluous_phpdoc_tags

  Removes @param, @return and @var tags that don’t provide any useful information.

• phpdoc_add_missing_param_annotation

  PHPDoc should contain @param for all params.

• phpdoc_align

  All items of the given PHPDoc tags must be either left-aligned or (by default) aligned vertically.

• phpdoc_annotation_without_dot

  PHPDoc annotation descriptions should not be a sentence.

• phpdoc_array_type (risky)

  PHPDoc array<T> type must be used instead of T[].

• phpdoc_indent

  Docblocks should have the same indentation as the documented subject.

• phpdoc_inline_tag_normalizer

  Fixes PHPDoc inline tags.

• phpdoc_line_span

  Changes doc blocks from single to multi line, or reversed. Works for class constants, properties and methods only.

• phpdoc_list_type (risky)

  PHPDoc list type must be used instead of array without a key.

• phpdoc_no_access

  @access annotations must be removed from PHPDoc.

• phpdoc_no_alias_tag

  No alias PHPDoc tags should be used.

• phpdoc_no_empty_return

  @return void and @return null annotations must be removed from PHPDoc.

• phpdoc_no_package

  @package and @subpackage annotations must be removed from PHPDoc.

• phpdoc_no_useless_inheritdoc

  Classy that does not inherit must not have @inheritdoc tags.

• phpdoc_order_by_value

  Order PHPDoc tags by value.

• phpdoc_order

  Annotations in PHPDoc should be ordered in defined sequence.

• phpdoc_param_order

  Orders all @param annotations in DocBlocks according to method signature.

• phpdoc_return_self_reference

  The type of @return annotations of methods returning a reference to itself must the configured one.

• phpdoc_scalar

  Scalar types should always be written in the same form. int not integer, bool not boolean, float not real or double.

• phpdoc_separation

  Annotations in PHPDoc should be grouped together so that annotations of the same type immediately follow each other. Annotations of a different type are separated by a single blank line.

• phpdoc_single_line_var_spacing

  Single line @var PHPDoc should have proper spacing.

• phpdoc_summary

  PHPDoc summary should end in either a full stop, exclamation mark, or question mark.

• phpdoc_tag_casing

  Fixes casing of PHPDoc tags.

• phpdoc_tag_type

  Forces PHPDoc tags to be either regular annotations or inline.

• phpdoc_to_comment

  Docblocks should only be used on structural elements.

• phpdoc_trim_consecutive_blank_line_separation

  Removes extra blank lines after summary and after description in PHPDoc.

• phpdoc_trim

  PHPDoc should start and end with content, excluding the very first and last line of the docblocks.

• phpdoc_types

  The correct case must be used for standard PHP types in PHPDoc.

• phpdoc_types_order

  Sorts PHPDoc types.

• phpdoc_var_annotation_correct_order

  @var and @type annotations must have type and name in the correct order.

• phpdoc_var_without_name

  @var and @type annotations of classy properties should not contain the name.

Return Notation

• no_useless_return

  There should not be an empty return statement at the end of a function.

• return_assignment

  Local, dynamic and directly referenced variables should not be assigned and directly returned by a function or method.

• simplified_null_return

  A return statement wishing to return void should not return null.

Semicolon

• multiline_whitespace_before_semicolons

  Forbid multi-line whitespace before the closing semicolon or move the semicolon to the new line for chained calls.

• no_empty_statement

  Remove useless (semicolon) statements.

• no_singleline_whitespace_before_semicolons

  Single-line whitespace before closing semicolon are prohibited.

• semicolon_after_instruction

  Instructions must be terminated with a semicolon.

• space_after_semicolon

  Fix whitespace after a semicolon.

Strict

• declare_strict_types (risky)

  Force strict types declaration in all files.

• strict_comparison (risky)

  Comparisons should be strict.

• strict_param (risky)

  Functions should be used with $strict param set to true.

String Notation

• escape_implicit_backslashes (deprecated)

  Escape implicit backslashes in strings and heredocs to ease the understanding of which are special chars interpreted by PHP and which not.

• explicit_string_variable

  Converts implicit variables into explicit ones in double-quoted strings or heredoc syntax.

• heredoc_closing_marker

  Unify heredoc or nowdoc closing marker.

• heredoc_to_nowdoc

  Convert heredoc to nowdoc where possible.

• multiline_string_to_heredoc

  Convert multiline string to heredoc or nowdoc.

• no_binary_string

  There should not be a binary flag before strings.

• no_trailing_whitespace_in_string (risky)

  There must be no trailing whitespace in strings.

• simple_to_complex_string_variable

  Converts explicit variables in double-quoted strings and heredoc syntax from simple to complex format (${ to {$).

• single_quote

  Convert double quotes to single quotes for simple strings.

• string_implicit_backslashes

  Handles implicit backslashes in strings and heredocs. Depending on the chosen strategy, it can escape implicit backslashes to ease the understanding of which are special chars interpreted by PHP and which not (escape), or it can remove these additional backslashes if you find them superfluous (unescape). You can also leave them as-is using ignore strategy.

• string_length_to_empty (risky)

  String tests for empty must be done against '', not with strlen.

• string_line_ending (risky)

  All multi-line strings must use correct line ending.

Whitespace

• array_indentation

  Each element of an array must be indented exactly once.

• blank_line_before_statement

  An empty line feed must precede any configured statement.

• blank_line_between_import_groups

  Putting blank lines between use statement groups.

• compact_nullable_type_declaration

  Remove extra spaces in a nullable type declaration.

• compact_nullable_typehint (deprecated)

  Remove extra spaces in a nullable typehint.

• heredoc_indentation

  Heredoc/nowdoc content must be properly indented.

• indentation_type

  Code MUST use configured indentation type.

• line_ending

  All PHP files must use same line ending.

• method_chaining_indentation

  Method chaining MUST be properly indented. Method chaining with different levels of indentation is not supported.

• no_extra_blank_lines

  Removes extra blank lines and/or blank lines following configuration.

• no_spaces_around_offset

  There MUST NOT be spaces around offset braces.

• no_spaces_inside_parenthesis (deprecated)

  There MUST NOT be a space after the opening parenthesis. There MUST NOT be a space before the closing parenthesis.

• no_trailing_whitespace

  Remove trailing whitespace at the end of non-blank lines.

• no_whitespace_in_blank_line

  Remove trailing whitespace at the end of blank lines.

• single_blank_line_at_eof

  A PHP file without end tag must always end with a single empty line feed.

• spaces_inside_parentheses

  Parentheses must be declared using the configured whitespace.

• statement_indentation

  Each statement must be indented.

• type_declaration_spaces

  Ensure single space between a variable and its type declaration in function arguments and properties.

• types_spaces

  A single space or none should be around union type and intersection type operators.