PHP 8.0: add support for attributes

[jrfnl]

PHP 8.0 | BCFile/FunctionDeclarations::get[Method]Parameters(): sync with upstream / bug fix for attributes leaking into type hint

This commit adds handling of parameter attributes to the File::getMethodParameters() method as per option [2] discussed in issue squizlabs/PHP_CodeSniffer#3298.

In practice this means that:

• [New] A new has_attributes index is introduced into the returned array which will hold a boolean value indicating whether attributes are attached to the parameter.
• [Unchanged] The content index in the returned array includes the textual representation of any attributes attached to a parameter.
• [Fixed] The type_hint and type_hint_token indexes will no longer be polluted (set incorrectly) with information belonging to the attribute(s) instead of to the type declaration.

Includes minor efficiency fix for handling of parenthesis and brackets in default values.

Includes dedicated unit test.

Refs:

• PHP 8.0 | File::getMethodParameters() needs to support attributes squizlabs/PHP_CodeSniffer#3298
• PHP 8.0 | File::getMethodParameters(): bug fix for attributes leaking into typehint squizlabs/PHP_CodeSniffer#3320

PHP 8.0 | Arrays::getDoubleArrowPtr(): handle attributes

As of PHP 8.0, attributes can be attached to functions, closures, arrow functions, classes, interfaces, traits, class constants, properties, methods and method parameters.

Attributes effectively instantiate a new instance of the class being referenced and can pass arguments to the constructor of that class.

As, while uncommon, closures or arrow functions could be used in an array key, there could be an attribute attached to these.

This adjusts the method to skip over attributes to prevent them confusing the double arrow pointer determination.

Includes tests.

Refs:

• https://wiki.php.net/rfc/attributes_v2

PHP 8.0 | Namespaces::determineNamespace(): skip over attributes

Efficiency tweak: skip over potentially large attribute declarations when walking up to find a namespace declaration.

Includes test.

Refs:

• https://wiki.php.net/rfc/attributes_v2

PHP 8.0 | PassedParameters::getParameters(): handle attributes

As of PHP 8.0, attributes can be attached to functions, closures, arrow functions, classes, interfaces, traits, class constants, properties, methods and method parameters.

Attributes effectively instantiate a new instance of the class being referenced and can pass arguments to the constructor of that class.

This has two implications for the PassedParameters::getParameters() method:

1. The class instantiation function call within an attribute should be handled by the method same as other class instantiation calls.
2. Attributes may, in select circumstances, be encountered within "parameters" and for efficiency and to prevent incorrect parsing, we should skip over them.

This commit adds a test confirming that situation [1] is already handled correctly.

Additionally, this commit adds the code to skip over attributes within parameters and adds a test covering that as well.

Refs:

• https://wiki.php.net/rfc/attributes_v2

PHP 8.0 | Variables::getMemberProperties(): correctly handle attributes

Sync with upstream PR squizlabs/PHP_CodeSniffer#3203 which ensures that attributes for properties are correctly regarded as "stop points" for gathering property information.

Ref:

• Tokenizer: add support for PHP8 attributes squizlabs/PHP_CodeSniffer#3203