Define missing macros variable in constructor

[ruudk]

When defining a macro in a template, the constructor looks like this:

    public function __construct(\Twig\Environment $env)
    {
        parent::__construct($env);
        $this->source = $this->getSourceContext();
        $this->parent = \false;
        $this->blocks = [];
        $macros["_self"] = $this->macros["_self"] = $this;
    }

The $macros variable does not exist resulting in:

Implicit array creation is not allowed - variable $macros does not exist.

/cc @fabpot Is this the best way to do it? Or would it be better to make this conditional instead?

Twig/src/Node/Expression/Variable/AssignTemplateVariable.php

Lines 31 to 36 in f3db1d1

	$compiler
	->addDebugInfo($this)
	->write('$macros[')
	->string($this->getAttribute('name'))
	->raw('] = ')
	;

[fabpot]

As $macros is not used in the constructor, I'm not sure I understand what it does/fixes.

[ruudk]

Before this PR, the compiled constructor looked like this:

    public function __construct(\Twig\Environment $env)
    {
        parent::__construct($env);
        $this->source = $this->getSourceContext();
        $this->parent = \false;
        $this->blocks = [];
        $macros["_self"] = $this->macros["_self"] = $this;
    }

Look at the last line of the method. PHPStan reports this error:

Implicit array creation is not allowed - variable $macros does not exist.

It's because by default, $macros[$name] = is prepended in

Twig/src/Node/Expression/Variable/AssignTemplateVariable.php

Lines 31 to 36 in f3db1d1

	$compiler
	->addDebugInfo($this)
	->write('$macros[')
	->string($this->getAttribute('name'))
	->raw('] = ')
	;

So we have 2 options:

1. add $macros = $this->macros; as the beginning of the constructor, just like doDisplay and block_ methods. Now PHPStan sees that $macros exists, and that adding something to it is fine.
2. remove the $macros[$name] = prefix when inside the constructor

[ruudk]

I feel option 2 makes more sense, shall I try that?

[fabpot]

This behavior comes from MacroAutoImportNodeVisitor, which has been removed in 3.15, so I don't think there is anything to fix.

[ruudk]

Ouch... then I'll wait for 3.15 to be released. Hopefully this can be done with #4415 included 🙏

[ruudk]

Closing as this will be solved with the release of 3.15 that removes MacroAutoImportNodeVisitor