ExtensionsTests.cs

public class ExtensionsTests
{
    [Test]
    public void IsText()
    {
        #region IsText

        True(FileExtensions.IsTextFile("file.txt"));
        False(FileExtensions.IsTextFile("file.bin"));
        True(FileExtensions.IsTextExtension(".txt"));
        False(FileExtensions.IsTextExtension(".bin"));
        True(FileExtensions.IsTextExtension("txt"));
        False(FileExtensions.IsTextExtension("bin"));

        #endregion
    }

    [Test]
    public void IsTextLegacy()
    {
#pragma warning disable CS0618 // Type or member is obsolete
        True(FileExtensions.IsText("file.txt"));
        False(FileExtensions.IsText("file.bin"));
        True(FileExtensions.IsText("c:/file.txt"));
        False(FileExtensions.IsText("c:/file.bin"));
        True(FileExtensions.IsText(".txt"));
        True(FileExtensions.IsText("txt"));
        False(FileExtensions.IsText(".bin"));
        False(FileExtensions.IsText("bin"));
#pragma warning restore CS0618 // Type or member is obsolete
    }

    [Test]
    public void AddTextExtension()
    {
        #region AddTextExtension

        FileExtensions.AddTextExtension(".ext1");
        True(FileExtensions.IsTextExtension(".ext1"));
        True(FileExtensions.IsTextFile("file.ext1"));

        #endregion

        FileExtensions.AddTextExtension("ext2");
        True(FileExtensions.IsTextExtension("ext2"));
        True(FileExtensions.IsTextFile("file.ext2"));
    }

    [Test]
    public void RemoveTextExtension()
    {
        #region RemoveTextExtension

        FileExtensions.AddTextExtension(".ext1");
        True(FileExtensions.IsTextExtension(".ext1"));
        FileExtensions.RemoveTextExtension(".ext1");
        False(FileExtensions.IsTextExtension(".ext1"));

        #endregion

        FileExtensions.AddTextExtension("ext1");
        True(FileExtensions.IsTextExtension("ext1"));
        FileExtensions.RemoveTextExtension("ext1");
        False(FileExtensions.IsTextExtension("ext1"));
    }
}