Enum: cases are constants

[weirdan]

Psalm should

• flag clashes between constants and cases: https://psalm.dev/r/30e59100be?php=8.1 , https://3v4l.org/fKOs6/rfc#vgit.master
• include cases into const wildcards: https://psalm.dev/r/838acc5287?php=8.1
• Support enum references in class constants: https://psalm.dev/r/d0b73490ba?php=8.1, https://3v4l.org/VlWW3/rfc#vgit.master

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/30e59100be

<?php

enum E {
    const A = 1;
    case A;
}

Psalm output (using commit f496cca):

No issues!

https://psalm.dev/r/838acc5287

<?php

enum E {
    const A = 1;
    case B;
}

/** @return E::* */
function f(): mixed {
    return E::B;
}

Psalm output (using commit f496cca):

ERROR: InvalidReturnStatement - 10:12 - The inferred type 'enum(E::B)' does not match the declared return type '1' for f

ERROR: InvalidReturnType - 8:13 - The declared return type '1' for f is incorrect, got 'enum(E::B)'