Add scoped everywhere

[Joy-less]

Adds the scoped keyword everywhere to ensure that stackalloc is always able to be used. This is especially relevant fo ValueStringBuilder(ReadOnlySpan<char> initialText).

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[linkdotnet]

Adds the scoped keyword everywhere to ensure that stackalloc is always able to be used. This is especially relevant fo ValueStringBuilder(ReadOnlySpan<char> initialText).

Wouldn't stackalloc be more prone to Span<char>? Where this isn't needed.

Therefore, which scenarios would we enable with that change?

[Joy-less]

Adds the scoped keyword everywhere to ensure that stackalloc is always able to be used. This is especially relevant fo ValueStringBuilder(ReadOnlySpan<char> initialText).

Wouldn't stackalloc be more prone to Span<char>? Where this isn't needed.

Therefore, which scenarios would we enable with that change?

I've played around and I'm not really sure what the purpose of the scoped keyword is. It seems like in many cases the compiler just allows stackalloc anyway. It's not really clear, but it seems like it's necessary in some situations.

Nevertheless, I noticed that scoped was used intermittently in the code base so I decided to use it absolutely everywhere where it's possible. I thought if we are using [MethodImpl.AggressiveInlining] everywhere we might as well use scoped everywhere as well. It doesn't hurt and it's a free optimisation wherever it is needed.

It's honestly up to you if you accept this.

[linkdotnet]

Imagine a function like:

public void Append(Span<char> str)

In theory we could do something inside like

public void Append(Span<char> str)
{
    this.buffer = str;

So now we have a function that calls that:

public void Append(Rune value)
{
    Span<char> valueChars = stackalloc char[2];
    var valueCharsWritten = value.EncodeToUtf16(valueChars);
    ReadOnlySpan<char> valueCharsSlice = valueChars[..valueCharsWritten];

    Append(valueCharsSlice);
}

Now the valueCharsSlice could potentially outlive the function (as we assign it to buffer), which will result in undefined/unsafe behavior. Basically, scoped will guarantee that we don't assign/outlive the scope.

So we could add this everywhere, as it doesn't "destroy" anything. Have to think about that.

[linkdotnet]

I do thunk it is absolutely fine to "decorate" the methods, that don't capture the context