// Unit testing class PythonSurrogateEscapeEncoding

[TestFixture(Category = "IronPython")]

public class SurrogateEscapeTest {

#region Round-trip tests

// Test 256 bytes sequence

public class Bytes256Test {

private byte[] _bytes;

[SetUp]

public void SetUp() {

_bytes = Enumerable.Range(0, 256).Select(c => (byte)c).ToArray();

}

[Test] public void Test256WithAscii() => TestRoundTrip(Encoding.ASCII, _bytes);

[Test] public void Test256WithPythonAscii() => TestRoundTrip(PythonAsciiEncoding.Instance, _bytes);

[Test] public void Test256WithUtf8() => TestRoundTrip(Encoding.UTF8, _bytes);

[Test] public void Test256WithDefault() => TestRoundTrip(Encoding.Default, _bytes);

[Test] public void Test256WithUnicode() => TestRoundTrip(Encoding.Unicode, _bytes);

[Test] public void Test256WithBigEndianUnicode() => TestRoundTrip(Encoding.BigEndianUnicode, _bytes);

[Test] public void Test256WithUtf32() => TestRoundTrip(Encoding.UTF32, _bytes);

[Test] public void Test256WithUtf32BE() => TestRoundTrip(new UTF32Encoding(bigEndian: true, byteOrderMark: false), _bytes);

}

// Test decoding/encoding a valid UTF-8 sequence

public class Utf8Test {

private byte[] _bytes;

[SetUp]

public void SetUp() {

// 12 bytes, rounded to multiply of 4 for the sake of UTF-32 test

_bytes = "\xd0\x9f\xd0\xb8\xd1\x82\xd0\xbe\xd0\xbd!!".AsBytes();

}

[Test] public void TestValidUtf8WithAscii() => TestRoundTrip(Encoding.ASCII, _bytes);

[Test] public void TestValidUtf8WithPythonAscii() => TestRoundTrip(PythonAsciiEncoding.Instance, _bytes);

[Test] public void TestValidUtf8WithUtf8() => TestRoundTrip(Encoding.UTF8, _bytes);

[Test] public void TestValidUtf8WithDefault() => TestRoundTrip(Encoding.Default, _bytes);

[Test] public void TestValidUtf8WithUnicode() => TestRoundTrip(Encoding.Unicode, _bytes);

[Test] public void TestValidUtf8WithBigEndianUnicode() => TestRoundTrip(Encoding.BigEndianUnicode, _bytes);

[Test] public void TestValidUtf8WithUtf32() => TestRoundTrip(Encoding.UTF32, _bytes);

[Test] public void TestValidUtf8WithUtf32BE() => TestRoundTrip(new UTF32Encoding(bigEndian: true, byteOrderMark: false), _bytes);

}

// Test decoding/encoding an invalid UTF-8 sequence

public class Utf8BrokenTest {

private byte[] _bytes;

[SetUp]

public void SetUp() {

// 12 bytes: two valid UTF-8 2-byte chars, one non-decodable byte,

// one UTF-8 2-byte char with a non-decodable byte inserted in between the UTF-8 bytes

// and final valid UTF-8 2-byte char

_bytes = "\xd0\x9f\xd0\xb8\x80\xd1\x20\x82\xd0\xbe\xd0\xbd".AsBytes();

}

[Test] public void TestBrokenUtf8WithAscii() => TestRoundTrip(Encoding.ASCII, _bytes);

[Test] public void TestBrokenUtf8WithPythonAscii() => TestRoundTrip(PythonAsciiEncoding.Instance, _bytes);

[Test] public void TestBrokenUtf8WithUtf8() => TestRoundTrip(Encoding.UTF8, _bytes);

[Test] public void TestBrokenUtf8WithDefault() => TestRoundTrip(Encoding.Default, _bytes);

[Test] public void TestBrokenUtf8WithUnicode() => TestRoundTrip(Encoding.Unicode, _bytes);

[Test] public void TestBrokenUtf8WithBigEndianUnicode() => TestRoundTrip(Encoding.BigEndianUnicode, _bytes);

[Test] public void TestBrokenUtf8WithUtf32() => TestRoundTrip(Encoding.UTF32, _bytes);

[Test] public void TestBrokenUtf8WithUtf32BE() => TestRoundTrip(new UTF32Encoding(bigEndian: true, byteOrderMark: false), _bytes);

}

// Note: UTF-7 is not round-trip safe in general

private static void TestRoundTrip(Encoding enc, byte[] bytes) {

Encoding penc = new PythonSurrogateEscapeEncoding(enc);

char[] chars1 = new char[penc.GetCharCount(bytes)];

penc.GetChars(bytes, 0, bytes.Length, chars1, 0);

char[] chars2 = penc.GetChars(bytes);

Assert.AreEqual(chars1, chars2);

byte[] bytes1 = penc.GetBytes(chars1);

byte[] bytes2 = new byte[penc.GetByteCount(chars1, 0, chars1.Length)];

penc.GetBytes(chars1, 0, chars1.Length, bytes2, 0);

Assert.AreEqual(bytes1, bytes2);

Assert.AreEqual(bytes, bytes1);

}

#endregion

#region Tests comparing with CPython results

// Test 256 bytes sequence

public class CPythonCompare256Tests {

private byte[] bytes;

[OneTimeSetUp]

public void OneTimeSetUp() {

#if NETCOREAPP

Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);

#endif

}

[SetUp]

public void SetUp() {

bytes = Enumerable.Range(0, 256).Select(c => (byte)c).ToArray();

}

// Compare ASCII handling with CPython results

[Test]

public void TestCompare256WithAscii() {

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.ASCII);

char[] chars = penc.GetChars(bytes);

string python_chars = "\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\x7f\udc80\udc81\udc82\udc83\udc84\udc85\udc86\udc87\udc88\udc89\udc8a\udc8b\udc8c\udc8d\udc8e\udc8f\udc90\udc91\udc92\udc93\udc94\udc95\udc96\udc97\udc98\udc99\udc9a\udc9b\udc9c\udc9d\udc9e\udc9f\udca0\udca1\udca2\udca3\udca4\udca5\udca6\udca7\udca8\udca9\udcaa\udcab\udcac\udcad\udcae\udcaf\udcb0\udcb1\udcb2\udcb3\udcb4\udcb5\udcb6\udcb7\udcb8\udcb9\udcba\udcbb\udcbc\udcbd\udcbe\udcbf\udcc0\udcc1\udcc2\udcc3\udcc4\udcc5\udcc6\udcc7\udcc8\udcc9\udcca\udccb\udccc\udccd\udcce\udccf\udcd0\udcd1\udcd2\udcd3\udcd4\udcd5\udcd6\udcd7\udcd8\udcd9\udcda\udcdb\udcdc\udcdd\udcde\udcdf\udce0\udce1\udce2\udce3\udce4\udce5\udce6\udce7\udce8\udce9\udcea\udceb\udcec\udced\udcee\udcef\udcf0\udcf1\udcf2\udcf3\udcf4\udcf5\udcf6\udcf7\udcf8\udcf9\udcfa\udcfb\udcfc\udcfd\udcfe\udcff";

Assert.AreEqual(python_chars, chars);

}

[Test]

public void TestCompare256WithPythonAscii() {

Encoding penc = new PythonSurrogateEscapeEncoding(PythonAsciiEncoding.Instance);

char[] chars = penc.GetChars(bytes);

string python_chars = "\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\x7f\udc80\udc81\udc82\udc83\udc84\udc85\udc86\udc87\udc88\udc89\udc8a\udc8b\udc8c\udc8d\udc8e\udc8f\udc90\udc91\udc92\udc93\udc94\udc95\udc96\udc97\udc98\udc99\udc9a\udc9b\udc9c\udc9d\udc9e\udc9f\udca0\udca1\udca2\udca3\udca4\udca5\udca6\udca7\udca8\udca9\udcaa\udcab\udcac\udcad\udcae\udcaf\udcb0\udcb1\udcb2\udcb3\udcb4\udcb5\udcb6\udcb7\udcb8\udcb9\udcba\udcbb\udcbc\udcbd\udcbe\udcbf\udcc0\udcc1\udcc2\udcc3\udcc4\udcc5\udcc6\udcc7\udcc8\udcc9\udcca\udccb\udccc\udccd\udcce\udccf\udcd0\udcd1\udcd2\udcd3\udcd4\udcd5\udcd6\udcd7\udcd8\udcd9\udcda\udcdb\udcdc\udcdd\udcde\udcdf\udce0\udce1\udce2\udce3\udce4\udce5\udce6\udce7\udce8\udce9\udcea\udceb\udcec\udced\udcee\udcef\udcf0\udcf1\udcf2\udcf3\udcf4\udcf5\udcf6\udcf7\udcf8\udcf9\udcfa\udcfb\udcfc\udcfd\udcfe\udcff";

Assert.AreEqual(python_chars, chars);

}

// Compare UTF-8 handling with CPython results

[Test]

public void TestCompare256WithUtf8() {

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.UTF8);

char[] chars = penc.GetChars(bytes);

string python_chars = "\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\x7f\udc80\udc81\udc82\udc83\udc84\udc85\udc86\udc87\udc88\udc89\udc8a\udc8b\udc8c\udc8d\udc8e\udc8f\udc90\udc91\udc92\udc93\udc94\udc95\udc96\udc97\udc98\udc99\udc9a\udc9b\udc9c\udc9d\udc9e\udc9f\udca0\udca1\udca2\udca3\udca4\udca5\udca6\udca7\udca8\udca9\udcaa\udcab\udcac\udcad\udcae\udcaf\udcb0\udcb1\udcb2\udcb3\udcb4\udcb5\udcb6\udcb7\udcb8\udcb9\udcba\udcbb\udcbc\udcbd\udcbe\udcbf\udcc0\udcc1\udcc2\udcc3\udcc4\udcc5\udcc6\udcc7\udcc8\udcc9\udcca\udccb\udccc\udccd\udcce\udccf\udcd0\udcd1\udcd2\udcd3\udcd4\udcd5\udcd6\udcd7\udcd8\udcd9\udcda\udcdb\udcdc\udcdd\udcde\udcdf\udce0\udce1\udce2\udce3\udce4\udce5\udce6\udce7\udce8\udce9\udcea\udceb\udcec\udced\udcee\udcef\udcf0\udcf1\udcf2\udcf3\udcf4\udcf5\udcf6\udcf7\udcf8\udcf9\udcfa\udcfb\udcfc\udcfd\udcfe\udcff";

Assert.AreEqual(python_chars, chars);

}

// Compare Windows-1252 (Western European Windows, variant of ISO-8859-1) handling with CPython results

[Test]

public void TestCompare256WithWindows1252() {

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.GetEncoding(1252));

Assert.AreEqual("windows-1252", penc.WebName.ToLowerInvariant());

char[] chars = penc.GetChars(bytes);

string python_chars = "\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\x7f€\udc81‚ƒ„…†‡ˆ‰Š‹Œ\udc8dŽ\udc8f\udc90‘’“”•–—˜™š›œ\udc9džŸ\xa0¡¢£¤¥¦§¨©ª«¬\xad®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ";

string encoded = new string(chars);

Assert.AreEqual(python_chars.Length, encoded.Length);

for (int i = 0; i < encoded.Length; i++) {

if (encoded[i] != python_chars[i]) {

// Known differences between Windows and Python (Unicode) implementation of Windows-1252

// https://en.wikipedia.org/wiki/Windows-1252

CollectionAssert.Contains(new[] { 0x81, 0x8d, 0x8f, 0x90, 0x9d }, i);

}

}

}

// Compare ISO-8859-1 (Western European) handling with CPython results

[Test]

public void TestCompare256WithIso8859_1() {

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.GetEncoding(28591));

Assert.AreEqual("iso-8859-1", penc.WebName);

char[] chars = penc.GetChars(bytes);

string python_chars = "\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\x7f\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f\x90\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f\xa0¡¢£¤¥¦§¨©ª«¬\xad®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ";

string encoded = new string(chars);

Assert.AreEqual(python_chars, encoded);

}

// Compare UTF-7 handling with CPython results

[Test]

public void TestCompare256WithUtf7() {

Encoding utf7 = new UTF7Encoding(allowOptionals: true);

Encoding penc = new PythonSurrogateEscapeEncoding(utf7);

// The following Python output is produced with python 3.4 but is not correct: it is missing the '+' character

string python_chars = "\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f !\"#$%&'()*,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\x7f\udc80\udc81\udc82\udc83\udc84\udc85\udc86\udc87\udc88\udc89\udc8a\udc8b\udc8c\udc8d\udc8e\udc8f\udc90\udc91\udc92\udc93\udc94\udc95\udc96\udc97\udc98\udc99\udc9a\udc9b\udc9c\udc9d\udc9e\udc9f\udca0\udca1\udca2\udca3\udca4\udca5\udca6\udca7\udca8\udca9\udcaa\udcab\udcac\udcad\udcae\udcaf\udcb0\udcb1\udcb2\udcb3\udcb4\udcb5\udcb6\udcb7\udcb8\udcb9\udcba\udcbb\udcbc\udcbd\udcbe\udcbf\udcc0\udcc1\udcc2\udcc3\udcc4\udcc5\udcc6\udcc7\udcc8\udcc9\udcca\udccb\udccc\udccd\udcce\udccf\udcd0\udcd1\udcd2\udcd3\udcd4\udcd5\udcd6\udcd7\udcd8\udcd9\udcda\udcdb\udcdc\udcdd\udcde\udcdf\udce0\udce1\udce2\udce3\udce4\udce5\udce6\udce7\udce8\udce9\udcea\udceb\udcec\udced\udcee\udcef\udcf0\udcf1\udcf2\udcf3\udcf4\udcf5\udcf6\udcf7\udcf8\udcf9\udcfa\udcfb\udcfc\udcfd\udcfe\udcff";

// Our implementation will refuse (correctly) to decode because the ',' after '+' is not valid thus requires escaping,

// but escaping of chars under 128 is not allowed.

Assert.Throws<DecoderFallbackException>(() => penc.GetChars(bytes));

// Let's try again without the '+'

bytes = bytes.Where(i => i != (byte)'+').ToArray();

char[] chars = penc.GetChars(bytes);

Assert.AreEqual(python_chars, chars);

// Now the encoding part

byte[] encoded_bytes = penc.GetBytes(chars);

byte[] expected_bytes = "+AAAAAQACAAMABAAFAAYABwAI-\t\n+AAsADA-\r+AA4ADwAQABEAEgATABQAFQAWABcAGAAZABoAGwAcAB0AHgAf- !\"#$%&'()*,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[+AFw-]^_`abcdefghijklmnopqrstuvwxyz{|}+AH4Af9yA3IHcgtyD3ITchdyG3IfciNyJ3Irci9yM3I3cjtyP3JDckdyS3JPclNyV3Jbcl9yY3Jncmtyb3Jzcndye3J/coNyh3KLco9yk3KXcptyn3Kjcqdyq3KvcrNyt3K7cr9yw3LHcstyz3LTctdy23LfcuNy53Lrcu9y83L3cvty/3MDcwdzC3MPcxNzF3Mbcx9zI3MncytzL3MzczdzO3M/c0NzR3NLc09zU3NXc1tzX3Njc2dza3Nvc3Nzd3N7c39zg3OHc4tzj3OTc5dzm3Ofc6Nzp3Orc69zs3O3c7tzv3PDc8dzy3PPc9Nz13Pbc99z43Pnc+tz73Pzc/dz+3P8-"

.Select(c => (byte)c).ToArray();

Assert.AreEqual(expected_bytes, encoded_bytes);

// Encoding the given chars with CPython produces the following byte string

byte[] python_bytes = "+AAAAAQACAAMABAAFAAYABwAI\t\n+AAsADA\r+AA4ADwAQABEAEgATABQAFQAWABcAGAAZABoAGwAcAB0AHgAf !\"#$%&'()*,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[+AFw]^_`abcdefghijklmnopqrstuvwxyz{|}+AH4Af9yA3IHcgtyD3ITchdyG3IfciNyJ3Irci9yM3I3cjtyP3JDckdyS3JPclNyV3Jbcl9yY3Jncmtyb3Jzcndye3J/coNyh3KLco9yk3KXcptyn3Kjcqdyq3KvcrNyt3K7cr9yw3LHcstyz3LTctdy23LfcuNy53Lrcu9y83L3cvty/3MDcwdzC3MPcxNzF3Mbcx9zI3MncytzL3MzczdzO3M/c0NzR3NLc09zU3NXc1tzX3Njc2dza3Nvc3Nzd3N7c39zg3OHc4tzj3OTc5dzm3Ofc6Nzp3Orc69zs3O3c7tzv3PDc8dzy3PPc9Nz13Pbc99z43Pnc+tz73Pzc/dz+3P8-"

.Select(c => (byte)c).ToArray();

// The sequences expected_bytes and python_bytes are NOT equal: .NET ends encoded blocks (starting with '+') with '-'

// Terminating encoded blocks with '-' is optional if not ambiguous.

// CPython doesn't terminate blocks with '-' if not mandatory, resulting in a more compact encoding.

// However, they both decode to the same text, although, again, CPython's version cannot be decoded using surrogateescape

char[] dotnet_decoded = penc.GetChars(encoded_bytes);

char[] python_decoded = utf7.GetChars(python_bytes);

Assert.AreEqual(chars, python_decoded);

Assert.AreEqual(chars, dotnet_decoded);

dotnet_decoded = utf7.GetChars(encoded_bytes);

Assert.AreEqual(chars, dotnet_decoded);

}

// Compare UTF-16 handling with CPython results

[Test]

public void TestCompare256Utf16() {

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.Unicode);

char[] chars = penc.GetChars(bytes);

char[] python_chars = (new[] { 0x0100, 0x0302, 0x0504, 0x0706, 0x0908, 0x0b0a, 0x0d0c, 0x0f0e, 0x1110, 0x1312, 0x1514, 0x1716, 0x1918, 0x1b1a, 0x1d1c, 0x1f1e, 0x2120, 0x2322, 0x2524, 0x2726, 0x2928, 0x2b2a, 0x2d2c, 0x2f2e, 0x3130, 0x3332, 0x3534, 0x3736, 0x3938, 0x3b3a, 0x3d3c, 0x3f3e, 0x4140, 0x4342, 0x4544, 0x4746, 0x4948, 0x4b4a, 0x4d4c, 0x4f4e, 0x5150, 0x5352, 0x5554, 0x5756, 0x5958, 0x5b5a, 0x5d5c, 0x5f5e, 0x6160, 0x6362, 0x6564, 0x6766, 0x6968, 0x6b6a, 0x6d6c, 0x6f6e, 0x7170, 0x7372, 0x7574, 0x7776, 0x7978, 0x7b7a, 0x7d7c, 0x7f7e, 0x8180, 0x8382, 0x8584, 0x8786, 0x8988, 0x8b8a, 0x8d8c, 0x8f8e, 0x9190, 0x9392, 0x9594, 0x9796, 0x9998, 0x9b9a, 0x9d9c, 0x9f9e, 0xa1a0, 0xa3a2, 0xa5a4, 0xa7a6, 0xa9a8, 0xabaa, 0xadac, 0xafae, 0xb1b0, 0xb3b2, 0xb5b4, 0xb7b6, 0xb9b8, 0xbbba, 0xbdbc, 0xbfbe, 0xc1c0, 0xc3c2, 0xc5c4, 0xc7c6, 0xc9c8, 0xcbca, 0xcdcc, 0xcfce, 0xd1d0, 0xd3d2, 0xd5d4, 0xd7d6, 0xdcd8, 0xdcd9, 0x1069dc, 0xdcde, 0xdcdf, 0xe1e0, 0xe3e2, 0xe5e4, 0xe7e6, 0xe9e8, 0xebea, 0xedec, 0xefee, 0xf1f0, 0xf3f2, 0xf5f4, 0xf7f6, 0xf9f8, 0xfbfa, 0xfdfc, 0xfffe })

.SelectMany(i => i <= 0xffff ? ((char)i).ToString() : char.ConvertFromUtf32(i)).ToArray();

Assert.AreEqual(python_chars, chars);

// byte[] python_bytes = ??? - CPython fails to encode the string it decoded itself; a bug in CPython?

byte[] bytes1 = penc.GetBytes(chars);

Assert.AreEqual(bytes, bytes1);

}

}

// Test sequence with surrogates

public class CPythonCompareSurrogateTests {

private byte[] bytes;

[SetUp]

public void SetUp() {

// In UTF-16LE: Lone high surrogate (invalid), surrogate pair: high-low (valid), lone low surrogate (invalid)

bytes = new byte[] { 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf };

}

[Test]

public void TesWithtUtf16() {

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.Unicode);

char[] chars = penc.GetChars(bytes);

char[] python_chars = (new[] { 0x0000dcd8, 0x0000dcd9, 0x001069dc, 0x0000dcde, 0x0000dcdf })

.SelectMany(i => i <= 0xffff ? ((char)i).ToString() : char.ConvertFromUtf32(i)).ToArray();

Assert.AreEqual(python_chars, chars);

// byte[] python_bytes = ??? - CPython fails on encoding the string it decoded itself; a bug in CPython?

byte[] bytes1 = penc.GetBytes(chars);

Assert.AreEqual(bytes, bytes1);

}

[Test]

public void TestWithUtf32() {

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.UTF32);

char[] chars = penc.GetChars(bytes);

char[] python_chars = (new[] { 0x0000dcd8, 0x0000dcd9, 0x0000dcda, 0x0000dcdb, 0x0000dcdc, 0x0000dcdd, 0x0000dcde, 0x0000dcdf })

.SelectMany(i => i <= 0xffff ? ((char)i).ToString() : char.ConvertFromUtf32(i)).ToArray();

Assert.AreEqual(python_chars, chars);

// byte[] python_bytes = ??? - CPython fails on encoding the string it decoded itself; a bug in CPython?

byte[] bytes1 = penc.GetBytes(chars);

Assert.AreEqual(bytes, bytes1);

}

}

#endregion

// Test incremental (block-wise) decoding/encoding

public class IncrementalTests {

private byte[] _bytes;

[SetUp]

public void SetUp() {

// In UTF-16LE: Lone high surrogate (invalid), surrogate pair: high-low (valid), lone low surrogate (invalid)

_bytes = new byte[] { 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf };

}

[Test]

public void TestIncrementalWithtAscii() {

// intersperse with ASCII letters

_bytes = _bytes.SelectMany((b, i) => new[] { (byte)('A' + i), b }).Concat(new[] { (byte)'Z' }).ToArray();

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.ASCII);

SurrogateTestHelpers.IncrementalTest(penc, _bytes, roundTrip: true);

}

[Test]

public void TestIncrementalWithtPythonAscii() {

// intersperse with ASCII letters

_bytes = _bytes.SelectMany((b, i) => new[] { (byte)('A' + i), b }).Concat(new[] { (byte)'Z' }).ToArray();

Encoding penc = new PythonSurrogateEscapeEncoding(PythonAsciiEncoding.Instance);

SurrogateTestHelpers.IncrementalTest(penc, _bytes, roundTrip: true);

}

[Test]

public void TestIncrementalWithtUtf16() {

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.Unicode);

SurrogateTestHelpers.IncrementalTest(penc, _bytes, roundTrip: true);

}

[Test]

public void TestIncrementalWithUtf32() {

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.UTF32);

SurrogateTestHelpers.IncrementalTest(penc, _bytes, roundTrip: true);

}

[Test]

public void TestIncrementalWithUtf8() {

// In UTF-8: Lone high surrogate (invalid), surrogate pair: high-low (valid), lone low surrogate (invalid)

_bytes = new byte[] { 0xed, 0xa7, 0x98, 0xed, 0xaf, 0x9a, 0xed, 0xb7, 0x9c, 0xed, 0xbf, 0x9e };

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.UTF8);

SurrogateTestHelpers.IncrementalTest(penc, _bytes, roundTrip: true);

}

}

public class EndiannessTests {

private byte[] _bytes1, _bytes2;

// U+0A00 is an unassigned character, U+000A is LF

[SetUp]

public void SetUp() {

_bytes1 = new byte[] { 0x0a, 0x00, 0x00, 0x00 };

_bytes2 = _bytes1.Reverse().ToArray();

}

[Test]

public void TestEndiannessWithtUtf16LE() {

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.Unicode);

Assert.AreEqual("\u000a\u0000", penc.GetChars(_bytes1));

Assert.AreEqual("\u0000\u0a00", penc.GetChars(_bytes2));

}

[Test]

public void TestEndiannessWithtUtf16BE() {

Encoding penc = new PythonSurrogateEscapeEncoding(Encoding.BigEndianUnicode);

Assert.AreEqual("\u0a00\u0000", penc.GetChars(_bytes1));

Assert.AreEqual("\u0000\u000a", penc.GetChars(_bytes2));

}

[Test]

public void TestEndiannessWithtUtf32LE() {

Encoding penc = new PythonSurrogateEscapeEncoding(new UTF32Encoding(bigEndian: false, byteOrderMark: false));

Assert.AreEqual("\u000a", penc.GetChars(_bytes1));

Assert.AreEqual("\udc00\udc00\udc00\udc0a", penc.GetChars(_bytes2));

}

[Test]

public void TestEndiannessWithtUtf32BE() {

Encoding penc = new PythonSurrogateEscapeEncoding(new UTF32Encoding(bigEndian: true, byteOrderMark: false));

Assert.AreEqual("\udc0a\udc00\udc00\udc00", penc.GetChars(_bytes1));

Assert.AreEqual("\u000a", penc.GetChars(_bytes2));

}

}

public class IncompleteSequenceTests {

private char[] _chars;

[SetUp]

public void SetUp() {

// one surrogate escape is not enough for wide-char encodings

_chars = "+++\udc41++".ToCharArray();

}

[Test] public void TestIncompleteSequenceWithtUtf16LE() => TestIncompleteSequence(Encoding.Unicode, 2);

[Test] public void TestIncompleteSequenceWithtUtf16BE() => TestIncompleteSequence(Encoding.BigEndianUnicode, 2);

[Test] public void TestIncompleteSequenceWithtUtf32LE() => TestIncompleteSequence(new UTF32Encoding(bigEndian: false, byteOrderMark: false), 4);

[Test] public void TestIncompleteSequenceWithtUtf32BE() => TestIncompleteSequence(new UTF32Encoding(bigEndian: true, byteOrderMark: false), 4);

public void TestIncompleteSequence(Encoding codec, int charWidth) {

Encoding penc = new PythonSurrogateEscapeEncoding(codec);

Assert.That(() => penc.GetBytes(_chars),

Throws.TypeOf<EncoderFallbackException>()

.With.Property("Index").EqualTo(3)

.And.Property("CharUnknown").EqualTo(_chars[3]));

var enc = penc.GetEncoder();

var bytes = new byte[_chars.Length * charWidth];

Assert.That(enc.GetByteCount(_chars, 0, 3, flush: false), Is.EqualTo(3 * charWidth));

Assert.That(() => enc.GetBytes(_chars, 0, 3, bytes, 0, flush: false), Throws.Nothing);

Assert.That(() => enc.GetBytes(_chars, 3, 2, bytes, 3 * charWidth, flush: false),

Throws.TypeOf<EncoderFallbackException>()

.With.Property("Index").EqualTo(0)

.And.Property("CharUnknown").EqualTo(_chars[3]));

enc.Reset();

Assert.That(enc.GetByteCount(_chars, 0, 4, flush: false), Is.EqualTo(3 * charWidth));

Assert.That(() => enc.GetBytes(_chars, 0, 4, bytes, 0, flush: false), Throws.Nothing);

Assert.That(() => enc.GetByteCount(_chars, 4, 1, flush: false),

Throws.TypeOf<EncoderFallbackException>()

.With.Property("Index").EqualTo(-1) // last char from previous increment

.And.Property("CharUnknown").EqualTo(_chars[3]));

}

}

}

// Unit testing class PythonSurrogatePassEncoding

[TestFixture(Category = "IronPython")]

public class SurrogatePassTest {

public class EncodingTests {

[Test]

public void TestAscii() {

// 'surrogatepass' is supported only for UTF-8, UTF-16LE, UTF-16BE, UTF-32LE, and UTF-32BE

// nevertheless, it can be used with other encodings as long as there are no encoding errors

Encoding penc = new PythonSurrogatePassEncoding(Encoding.ASCII);

// clean ASCII

Assert.AreEqual("abc".AsBytes(), penc.GetBytes("abc"));

// Attempting to encode surrogates to ASCII will throw an exception.

// Note that this is CPython 3.5 behaviour, CPython 3.4 will happily contaminate ASCII with UTF-8 encoded surrogates.

// lone high surrogate

Assert.Throws<EncoderFallbackException>(() => penc.GetBytes("\ud810"));

// lone low surrogate

Assert.Throws<EncoderFallbackException>(() => penc.GetBytes("\udc0a"));

// invalid surrogate pair (low, high)

Assert.Throws<EncoderFallbackException>(() => penc.GetBytes("\ude51\uda2f"));

}

[Test]

public void TestUtf7() {

// "surrogatepass" is not supported for UTF-7 per se,

// but UTF-7 is supposed to encode any surogate characters into its ASCII mangled form

// without requiring any fallback support

Encoding penc = new PythonSurrogatePassEncoding(new UTF7Encoding(allowOptionals: true));

// lone high surrogate

Assert.AreEqual("abc+2BA-xyz".AsBytes(), penc.GetBytes("abc\ud810xyz"));

// lone low surrogate

Assert.AreEqual("abc+3Ao-xyz".AsBytes(), penc.GetBytes("abc\udc0axyz"));

// invalid surrogate pair (low, high)

Assert.AreEqual("abc+3lHaLw-xyz".AsBytes(), penc.GetBytes("abc\ude51\uda2fxyz"));

}

[Test]

public void TestUtf8() {

Encoding penc = new PythonSurrogatePassEncoding(Encoding.UTF8);

// lone high surrogate

Assert.AreEqual("abc\xed\xa0\x90xyz".AsBytes(), penc.GetBytes("abc\ud810xyz"));

// lone low surrogate

Assert.AreEqual("abc\xed\xb0\x8axyz".AsBytes(), penc.GetBytes("abc\udc0axyz"));

// invalid surrogate pair (low, high)

Assert.AreEqual("abc\xed\xb9\x91\xed\xa8\xafxyz".AsBytes(), penc.GetBytes("abc\ude51\uda2fxyz"));

}

[Test]

public void TestUtf16LE() {

Encoding penc = new PythonSurrogatePassEncoding(Encoding.Unicode);

// lone high surrogate

Assert.AreEqual("\x10\xd8".AsBytes(), penc.GetBytes("\ud810"));

// lone low surrogate

Assert.AreEqual("\n\xdc".AsBytes(), penc.GetBytes("\udc0a"));

// invalid surrogate pair (low, high)

Assert.AreEqual("Q\xde/\xda".AsBytes(), penc.GetBytes("\ude51\uda2f"));

}

[Test]

public void TestUtf16BE() {

Encoding penc = new PythonSurrogatePassEncoding(Encoding.BigEndianUnicode);

// lone high surrogate

Assert.AreEqual("\xd8\x10".AsBytes(), penc.GetBytes("\ud810"));

// lone low surrogate

Assert.AreEqual("\xdc\n".AsBytes(), penc.GetBytes("\udc0a"));

// invalid surrogate pair (low, high)

Assert.AreEqual("\xdeQ\xda/".AsBytes(), penc.GetBytes("\ude51\uda2f"));

}

[Test]

public void TestUtf32LE() {

Encoding penc = new PythonSurrogatePassEncoding(new UTF32Encoding(bigEndian: false, byteOrderMark: false));

// lone high surrogate

Assert.AreEqual("\x10\xd8\x00\x00".AsBytes(), penc.GetBytes("\ud810"));

// lone low surrogate

Assert.AreEqual("\n\xdc\x00\x00".AsBytes(), penc.GetBytes("\udc0a"));

// invalid surrogate pair (low, high)

Assert.AreEqual("Q\xde\x00\x00/\xda\x00\x00".AsBytes(), penc.GetBytes("\ude51\uda2f"));

}

[Test]

public void TestUtf32BE() {

Encoding penc = new PythonSurrogatePassEncoding(new UTF32Encoding(bigEndian: true, byteOrderMark: false));

// lone high surrogate

Assert.AreEqual("\x00\x00\xd8\x10".AsBytes(), penc.GetBytes("\ud810"));

// lone low surrogate

Assert.AreEqual("\x00\x00\xdc\n".AsBytes(), penc.GetBytes("\udc0a"));

// invalid surrogate pair (low, high)

Assert.AreEqual("\x00\x00\xdeQ\x00\x00\xda/".AsBytes(), penc.GetBytes("\ude51\uda2f"));

}

}

public class DecodingTests {

[Test]

public void TestAscii() {

// 'surrogatepass' is supported only for UTF-8, UTF-16LE, UTF-16BE, UTF-32LE, and UTF-32BE

// nevertheless, it can be used with other encodings as long as there are no encoding errors

Encoding penc = new PythonSurrogatePassEncoding(Encoding.ASCII);

// clean ASCII

Assert.AreEqual("abc", penc.GetChars("abc".AsBytes()));

// Attempting to decode surrogates from ASCII will throw an exception.

// Note that this is CPython 3.5 behaviour, CPython 3.4 will will blindly extract UTF-8 encoded surrogates from ASCII.

// lone high surrogate in UTF-8

Assert.Throws<DecoderFallbackException>(() => penc.GetChars("\xed\xa0\x90".AsBytes()));

// lone low surrogate in UTF-8

Assert.Throws<DecoderFallbackException>(() => penc.GetChars("\xed\xb0\x8a".AsBytes()));

// invalid surrogate pair (low, high) in UTF-8

Assert.Throws<DecoderFallbackException>(() => penc.GetChars("\xed\xb9\x91\xed\xa8\xaf".AsBytes()));

}

[Test]

public void TestUtf7() {

// "surrogatepass" is not supported for UTF-7 per se,

// but UTF-7 is supposed to decode any surogate characters from its ASCII mangled form

// without requiring any fallback support

Encoding penc = new PythonSurrogatePassEncoding(new UTF7Encoding(allowOptionals: true));

// lone high surrogate

Assert.AreEqual("abc\ud810xyz", penc.GetChars("abc+2BA-xyz".AsBytes()));

// lone low surrogate

Assert.AreEqual("abc\udc0axyz", penc.GetChars("abc+3Ao-xyz".AsBytes()));

// invalid surrogate pair (low, high)

Assert.AreEqual("abc\ude51\uda2fxyz", penc.GetChars("abc+3lHaLw-xyz".AsBytes()));

}

[Test]

public void TestUtf8() {

Encoding penc = new PythonSurrogatePassEncoding(Encoding.UTF8);

// lone high surrogate

Assert.AreEqual("abc\ud810xyz", penc.GetChars("abc\xed\xa0\x90xyz".AsBytes()));

// lone low surrogate

Assert.AreEqual("abc\udc0axyz", penc.GetChars("abc\xed\xb0\x8axyz".AsBytes()));

// invalid surrogate pair (low, high)

Assert.AreEqual("abc\ude51\uda2fxyz", penc.GetChars("abc\xed\xb9\x91\xed\xa8\xafxyz".AsBytes()));

// valid surrogate pair (high, low)

Assert.AreEqual("abc\uda2f\ude51xyz", penc.GetChars("abc\xed\xa8\xaf\xed\xb9\x91xyz".AsBytes()));

var chars = new char[9];

// broken lone high surrogate

var bytes = "abc\xed-\xa0\x90xyz".AsBytes();

Assert.That(() => penc.GetChars(bytes),

Throws.TypeOf<DecoderFallbackException>()