phpstan: PHPDoc block is ignored for closures/anonymous functions

Bug report

spl_autoload_register(
    /**
     * @param class-string $class_name The fully-qualified class name.
     * @return void
     */
    static function ($class_name) {

Parameter #1 $autoload_function of function spl_autoload_register expects callable(string): void, Closure(mixed): mixed given.

Code snippet that reproduces the problem

https://phpstan.org/r/56909d36-0d70-4c8d-990a-be01e822c572

Expected output

No error.

About this issue

Original URL
State: open
Created 4 years ago
Reactions: 11
Comments: 16 (11 by maintainers)

Commits related to this issue

Add a note and TODO about phpstan/phpstan#3770. — committed to loophp/collection by drupol 3 years ago
Update Span and Partition operations. (#148) * show partition failure (cherry picked from commit 9eaf340cc37746f65d6626559e76be4336f50c14) * Another example (cherry picked from commit 5afe28... — committed to loophp/collection by drupol 3 years ago

Most upvoted comments

This feature isn’t hard but there’s quite a few places we need to think of. I made a list of points that we need to keep track of during development:

Implement this for both Closure and ArrowFunction expressions.
The PHPDoc needs to be read when entering the closure. For functions and class methods, this is done in places where NodeScopeResolver::getPhpDocs() is called: https://github.com/phpstan/phpstan-src/blob/6506d876ed0cfb625af3d749a19270706df7640b/src/Analyser/NodeScopeResolver.php#L3820
- When a closure is passed to a precise callable signature, the parameters are inferred based on that signature: https://github.com/phpstan/phpstan-src/blob/6506d876ed0cfb625af3d749a19270706df7640b/src/Analyser/NodeScopeResolver.php#L2931-L2946
- When a closure is passed to array_map, the first parameter type is inferred from the array passed to array_map (for the purpose of analysing the closure body): https://github.com/phpstan/phpstan-src/blob/6506d876ed0cfb625af3d749a19270706df7640b/src/Reflection/ParametersAcceptorSelector.php#L74-L106
- When a closure is passed to array_filter, the first parameter type is inferred from the array passed to array_filter (for the purpose of analysing the closure body): https://github.com/phpstan/phpstan-src/blob/6506d876ed0cfb625af3d749a19270706df7640b/src/Reflection/ParametersAcceptorSelector.php#L108-L150
The PHPDoc needs to be read when inferring the type of the Closure and ArrowFunction expressions: https://github.com/phpstan/phpstan-src/blob/6506d876ed0cfb625af3d749a19270706df7640b/src/Analyser/MutatingScope.php#L1616-L1773.
- The closure body is read to figure out the return type. When @return is present in the PHPDoc, we probably don’t need to do this inference.
- For array_map call this is used to figure out the return type of the array_map call.

The extra features mentioned in the list subitems should probably be turned off when PHPDoc is present.

Additionally, there should be new rules:

Similar rule to IncompatiblePhpDocTypeRule - about nonexistent parameter names, about incompatible types like string in @param but for native type int etc.
Similar rule to InvalidPhpDocTagValueRule for PHPDoc parse errors
FunctionDefinitionCheck::checkAnonymousFunction also needs to be updated to read the PHPDocs
We also need to make sure that generics work and add a rule for that like FunctionTemplateTypeRule.

This should be done over multiple small PRs which is the way I like to work.

I also offer to implement this for a fee paid against an invoice I’d issue. My estimate as what this would cost to have this developed by myself is 1500-2000 EUR. Feel free to reach out if you’re interested 😃

ondrejmirtes on Apr 21, 2022