public void CanEnumerateReadonlySpan()
{
// Test example taken from.
// https://docs.microsoft.com/en-us/dotnet/api/system.text.rune?view=net-5.0#when-to-use-the-rune-type
const string text = "𐓏𐓘𐓻𐓘𐓻𐓟 𐒻𐓟";
int letterCount = 0;
foreach (CodePoint codePoint in text.AsSpan().EnumerateCodePoints())
{
if (CodePoint.IsLetter(codePoint))
{
letterCount++;
}
}
Assert.Equal(8, letterCount);
}
public void CanEnumerateInvalidReadonlySpan()
{
// The string below contains 2 combining characters then
// a single high surrogate code unit, then 2 more sets or combining characters.
// 'ā̈' 'b' '�' 'ç'
const string text = "a\u0304\u0308b\ud800c\u0327";
int letterCount = 0;
int codePointCount = 0;
foreach (CodePoint codePoint in text.AsSpan().EnumerateCodePoints())
{
if (CodePoint.IsLetter(codePoint))
{
letterCount++;
}
codePointCount++;
}
Assert.Equal(3, letterCount);
Assert.Equal(7, codePointCount);
}
public static void CodePointIsLetter(UnicodeInfoTestData testData) => Assert.Equal(testData.IsLetter, CodePoint.IsLetter(testData.ScalarValue));