ArgumentTypeCoercion for typecasted variables

[kkmuffme]

When a variable is typecasted and clearly is a positive int, psalm thinks it's generic int:

https://psalm.dev/r/c1e0a9efd4

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/c1e0a9efd4

<?php

$time = (int) round( 1.23 );
sleep( $time );

$time = (int) '123';
sleep( $time );

Psalm output (using commit 9943efb):

ERROR: ArgumentTypeCoercion - 4:8 - Argument 1 of sleep expects 0|positive-int, parent type int provided

ERROR: ArgumentTypeCoercion - 7:8 - Argument 1 of sleep expects 0|positive-int, parent type int provided

[orklah]

These are two easy issues.

The one with round must be fixed by a return type provider. We already have a few of them, they're easy to create. You can look at https://github.com/vimeo/psalm/blob/6abce3525ac34f815aaa3b7953739b744ca5c39e/src/Psalm/Internal/Provider/ReturnTypeProvider/StrReplaceReturnTypeProvider.php for an example

The one with just the case must be fixed in CastAnalyzer. Most specifically, in this condition:

psalm/src/Psalm/Internal/Analyzer/Statements/Expression/CastAnalyzer.php

Line 43 in bf99345

if ($stmt instanceof PhpParser\Node\Expr\Cast\Int_) {

Here, we could look at the Union content, if we have a single string and if it's a numeric, we could just cast to int in Psalm and return a literal int with this value instead of returning the generic int

[orklah]

Half of the issue was resolved

[kkmuffme]

Second half has PR created, #8366