[lang-ref] ( is_upper ) ( csharp )

    [Theory]
    [InlineData("ABC", true)]
    [InlineData("Abc", false)]
    [InlineData("abc", false)]
    [InlineData("ABC DEF", false)] // space is not upper
    [InlineData(" ", false)]
    [InlineData("", true)] // true if empty ( this is just the behavior of [].All() )
    public void TestIsUpper(string text, bool expected)
    {
        // text.All(char.IsUpper)

        bool actual = text.All(char.IsUpper);


        Assert.Equal(expected, actual);
    }
}