void AssertPreviewText(string path, string expected)
{
var previewer = new PlainTextPreviewer();
var buffer = new byte[16 * 1024];
string actual;
int nread;
Assert.AreEqual(TextFormat.Plain, previewer.InputFormat);
using (var stream = File.OpenRead(path))
nread = stream.Read(buffer, 0, buffer.Length);
var text = Encoding.UTF8.GetString(buffer, 0, nread);
actual = previewer.GetPreviewText(text);
Assert.AreEqual(expected, actual, "GetPreviewText(string)");
using (var stream = new MemoryStream(buffer, 0, nread, false)) {
actual = previewer.GetPreviewText(stream, "utf-8");
Assert.AreEqual(expected, actual, "GetPreviewText(Stream, string)");
stream.Position = 0;
actual = previewer.GetPreviewText(stream, Encoding.UTF8);
Assert.AreEqual(expected, actual, "GetPreviewText(Stream, Encoding)");
stream.Position = 0;
using (var reader = new StreamReader(stream, Encoding.UTF8, false, 4096, true)) {
actual = previewer.GetPreviewText(stream, Encoding.UTF8);
Assert.AreEqual(expected, actual, "GetPreviewText(TextReader)");
}
}
}
public void TestEmptyText()
{
var previewer = new PlainTextPreviewer();
Assert.AreEqual(string.Empty, previewer.GetPreviewText(string.Empty), "string");
using (var reader = new StringReader(string.Empty))
Assert.AreEqual(string.Empty, previewer.GetPreviewText(reader), "TextReader");
using (var stream = new MemoryStream(new byte[0], false)) {
Assert.AreEqual(string.Empty, previewer.GetPreviewText(stream, "x-unknown"), "Stream, string");
Assert.AreEqual(string.Empty, previewer.GetPreviewText(stream, Encoding.UTF8), "Stream, Encoding");
}
}
public void TestArgumentExceptions()
{
var previewer = new PlainTextPreviewer();
Assert.Throws <ArgumentOutOfRangeException> (() => previewer.MaximumPreviewLength = 0);
Assert.Throws <ArgumentOutOfRangeException> (() => previewer.MaximumPreviewLength = 1025);
Assert.Throws <ArgumentNullException> (() => previewer.GetPreviewText((string)null));
Assert.Throws <ArgumentNullException> (() => previewer.GetPreviewText((TextReader)null));
Assert.Throws <ArgumentNullException> (() => previewer.GetPreviewText((Stream)null, "charset"));
Assert.Throws <ArgumentNullException> (() => previewer.GetPreviewText(Stream.Null, (string)null));
Assert.Throws <ArgumentNullException> (() => previewer.GetPreviewText((Stream)null, Encoding.ASCII));
Assert.Throws <ArgumentNullException> (() => previewer.GetPreviewText(Stream.Null, (Encoding)null));
}
