potentially polymorphic call with model instance inside model function

I'm porting a CI3 app to CI4 and need to call one model method inside another model method.  Can someone tell me why this produces no warning:

PHP Code:

public function get_value(): int
 {
 $this->sale = model('Sale');
 return $this->sale->get_quote_number_for_year();
 }
} 


But if I do this:

PHP Code:

public function get_value(): int
 {
 $sale = model('Sale');
 return $sale->get_quote_number_for_year();
 }
} 


I get a warning from PhpStorm
Potentially polymorphic call. Model does not have members in its hierarchy

The function signature for get_quote_number_for_year() is
public function Sale::get_quote_number_for_year($year = '', $start_from = 0) int

What if model(Sale::class)?

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What if model(Sale::class)?

with

PHP Code:

$sale = model(Sale::class); 


The warning goes away. The puzzling thing for me is that the documentation (https://codeigniter.com/user_guide/models/model.html) doesn't give examples this way but gives examples using $modelName =

Maybe this has to do with me instantiating a model inside a model instead of a class? What is the best practice here? $this->sale = model('Sale') or $sale = model(Sale::class)?

Did you specify the type for $this->sale ?

model(Sale::class) and model('Sale') are exactly the same for CodeIgniter,
but a bit different for PHPStan.

I recommend model(Sale::class) because PHPStan knows the return value type (Sale::class).
And the type is correct more than 99%.

---

See also https://www.jetbrains.com/help/phpstorm/...-call.html

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Did you specify the type for $this->sale ?

model(Sale::class) and model('Sale') are exactly the same for CodeIgniter,
but a bit different for PHPStan.

I recommend model(Sale::class) because PHPStan knows the return value type (Sale::class).
And the type is correct more than 99%.

---

See also https://www.jetbrains.com/help/phpstorm/...-call.html

I did not specify the type for $this->sale. Just what you see in the code I posted.

I do have a use statement at the top of the file

PHP Code:

namespace App\Models\Tokens;

use app\Models\Sale; 


<?php

namespace App\Models;

I cannot reproduce the warning.
I got no warning.

PHP Code:

use CodeIgniter\Model;

class Sale extends Model
{
} 


PHP Code:

<?php

namespace App\Models;

use CodeIgniter\Model;

class Test extends Model
{
    public function get_value(): int
    {
        $sale = model('Sale');

        return $sale->get_quote_number_for_year();
    }
} 


---

I don't know why you got the warning.

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