Internal: enabling taint/unused analysis will modify unrelated behavior when comparing types

[kkmuffme]

Union "equals" has 4 params:

psalm/src/Psalm/Type/UnionTrait.php

Line 1381 in f268dfa

public function equals(

The "parent node" is generally only set when taint/unused is enabled, which means that e.g. comparing arrays will return different results when taint/unused is on vs when it's not, bc the Atomic type only has 2 params:
https://github.com/vimeo/psalm/blob/5.x/src/Psalm/Type/Atomic.php#L776

and e.g. https://github.com/vimeo/psalm/blob/5.x/src/Psalm/Type/Atomic/TArray.php#L87 uses the Union equals, which then causes the "equals" to return different results.

This is extremely unintuitive and causes errors to be reported/missing that are unrelated to either setting.

[psalm-github-bot]

Hey @kkmuffme, can you reproduce the issue on https://psalm.dev ?