Str::headline does not work with umlauts

[cemrich]

• Laravel Version: 8.78.1
• PHP Version: 8.1.1
• Database Driver & Version:

Description:

Illuminate\Support\Str::headline does not support umlauts (like ö,ä,ü). There are two related bugs I can see:

1. Uppercase umlauts are not detected as uppercase.
2. Umlauts at the beginning of a word do not get capitalized.

Steps To Reproduce:

Umlauts at the beginning of a word do not get capitalized

public function test_make_umlauts_uppercase() {
    $input = 'ärmere-öffentliche-überraschungen-sind-öde';
    $expected = 'Ärmere Öffentliche Überraschungen Sind Öde';
    $output = Str::headline($input);
    $this->assertEquals($expected, $output);
}

Yields the output:

Failed asserting that two strings are equal.
Expected :'Ärmere Öffentliche Überraschungen Sind Öde'
Actual   :'ärmereöffentlicheüberraschungen Sindöde'

Uppercase umlauts are not detected as uppercase

public function test_detect_uppercase_umlauts() {
    $input = 'sindÖdeUndSo';
    $expected = 'Sind Öde Und So';
    $output = Str::headline($input);
    $this->assertEquals($expected, $output);
}

Yields the output:

Failed asserting that two strings are equal.
Expected :'Sind Öde Und So'
Actual   :'SindÖde Und So'

[foremtehan]

@stevebauman

[driesvints]

We'd welcome PR's for this, thank you.

[stevebauman]

This is because ucwords() doesn't handle unicode characters:

// ärmere öffentliche
echo ucwords('ärmere öffentliche');

This means Str::studly() or anything relying on that method also does not work with unicode characters.

We'll have to be crafty and use mb_convert_case(). I'll see if I can come up with something 👍