gui-cs.Terminal.Gui/UnitTests/Text/StringTests.cs

namespace Terminal.Gui.TextTests;

#nullable enable

public class StringTests
{
    [Fact]
    public void TestGetColumns_Empty ()
    {
        var str = string.Empty;
        Assert.Equal (0, str.GetColumns ());
    }

    [Theory]
    [InlineData ("a", 1)]
    [InlineData ("á", 1)]
    [InlineData ("ab", 2)]
    [InlineData ("áé", 2)]
    [InlineData ("abc", 3)]
    [InlineData ("áéí", 3)]
    [InlineData ("abcd", 4)]
    public void TestGetColumns_MultiRune (string str, int expected) { Assert.Equal (expected, str.GetColumns ()); }

    // Test non-BMP codepoints 
    // Face with Tears of Joy Emoji (😂), Unicode U+1F602 is 2 columns wide
    [Theory]
    [InlineData ("😂", 2)]
    [InlineData ("😂😂", 4)]
    public void TestGetColumns_MultiRune_NonBMP (string str, int expected) { Assert.Equal (expected, str.GetColumns ()); }

    // Test known wide codepoints
    [Theory]
    [InlineData ("🙂", 2)]
    [InlineData ("a🙂", 3)]
    [InlineData ("🙂a", 3)]
    [InlineData ("👨‍👩‍👦‍👦", 8)]
    [InlineData ("👨‍👩‍👦‍👦🙂", 10)]
    [InlineData ("👨‍👩‍👦‍👦🙂a", 11)]
    [InlineData ("👨‍👩‍👦‍👦a🙂", 11)]
    [InlineData ("👨‍👩‍👦‍👦👨‍👩‍👦‍👦", 16)]
    [InlineData ("山", 2)] // The character for "mountain" in Chinese/Japanese/Korean (山), Unicode U+5C71
    [InlineData ("山🙂", 4)] // The character for "mountain" in Chinese/Japanese/Korean (山), Unicode U+5C71
    //[InlineData ("\ufe20\ufe21", 2)] // Combining Ligature Left Half ︠ - U+fe20 -https://github.com/microsoft/terminal/blob/main/src/types/unicode_width_overrides.xml
    //				 // Combining Ligature Right Half - U+fe21 -https://github.com/microsoft/terminal/blob/main/src/types/unicode_width_overrides.xml
    public void TestGetColumns_MultiRune_WideBMP (string str, int expected) { Assert.Equal (expected, str.GetColumns ()); }

    [Fact]
    public void TestGetColumns_Null ()
    {
        string? str = null;
        Assert.Equal (0, str!.GetColumns ());
    }

    [Fact]
    public void TestGetColumns_SingleRune ()
    {
        var str = "a";
        Assert.Equal (1, str.GetColumns ());
    }
}