IDE0290 code fix is invalid in ref struct

[meziantou]

Version Used: '4.11.0-1.24229.8 (28985c0)'. Language version: 12.0

Steps to Reproduce:

https://sharplab.io/#v2:EYLgtghglgdgPgAQEwEYCwAoTAnApgMwAIBnAF2wFcBjUwgZQjAAcAbXTAb00J8KeygA3CKVyEASrggATAPIwWATzpMIMADxUAFhGwA+QgH0y2ANyZuvBAGZ6jVrgAUkmfKUq1mnfpLkAlJY8XBi8oUYmhAC8vmaBhAC+FiFWtggALIQAsgD2grgAcrgAHqSOAclBcaHC2CSqMFHh5OYVCZiJGEA

ref struct Sample
{
    private ReadOnlySpan<char> _str;

    public Sample(ReadOnlySpan<char> str)
    {
        _str = str;
    }

    public void MoveNext()
    {
        var span = _str;
    }
}

Use the fix to convert to primary constructor and remove field

ref struct Sample(ReadOnlySpan<char> str)
{
    public void MoveNext()
    {
        // ❌ CS9110 Cannot use primary constructor parameter 'str' that has ref-like type inside an instance member
        var span = str;
    }
}

Diagnostic Id: IDE0290 Use primary Constructor

Expected Behavior: The code fix is not suggested

Actual Behavior: The code fix is suggested

[GiovanniBraconi]

If nobody is working on this issue, i'll happily take a look at it 😃

[CyrusNajmabadi]

@GiovanniBraconi Absolutely!