Fix bug in binascii uu encoding. Pass more related unit tests. (#5160)

* Fix bug in binascii, passes more unit tests.

* Pass more additional tests due to this PR.

Lib/test/test_binascii.py

@@ -38,8 +38,6 @@ class BinASCIITest(unittest.TestCase):
             self.assertTrue(hasattr(getattr(binascii, name), '__call__'))
             self.assertRaises(TypeError, getattr(binascii, name))
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_returned_value(self):
         # Limit to the minimum of all limits (b2a_uu)
         MAX_ALL = 45
@@ -186,8 +184,6 @@ class BinASCIITest(unittest.TestCase):
         assertInvalidLength(b'a' * (4 * 87 + 1))
         assertInvalidLength(b'A\tB\nC ??DE')  # only 5 valid characters
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_uu(self):
         MAX_UU = 45
         for backtick in (True, False):
@@ -404,8 +400,6 @@ class BinASCIITest(unittest.TestCase):
         # crc_hqx needs 2 arguments
         self.assertRaises(TypeError, binascii.crc_hqx, "test", 0)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_unicode_a2b(self):
         # Unicode strings are accepted by a2b_* functions.
         MAX_ALL = 45

Lib/test/test_codecs.py

@@ -2946,8 +2946,6 @@ else:
 
 class TransformCodecTest(unittest.TestCase):
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_basics(self):
         binput = bytes(range(256))
         for encoding in bytes_transform_encodings:
@@ -2959,8 +2957,6 @@ class TransformCodecTest(unittest.TestCase):
                 self.assertEqual(size, len(o))
                 self.assertEqual(i, binput)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_read(self):
         for encoding in bytes_transform_encodings:
             with self.subTest(encoding=encoding):
@@ -2969,8 +2965,6 @@ class TransformCodecTest(unittest.TestCase):
                 sout = reader.read()
                 self.assertEqual(sout, b"\x80")
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_readline(self):
         for encoding in bytes_transform_encodings:
             with self.subTest(encoding=encoding):

Lib/test/test_uu.py

@@ -75,8 +75,6 @@ class UUTest(unittest.TestCase):
         with self.assertRaises(TypeError):
             uu.encode(inp, out, "t1", 0o644, True)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_decode(self):
         for backtick in True, False:
             inp = io.BytesIO(encodedtextwrapped(0o666, "t1", backtick=backtick))
@@ -110,8 +108,6 @@ class UUTest(unittest.TestCase):
         except uu.Error as e:
             self.assertEqual(str(e), "No valid begin line found in input file")
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_garbage_padding(self):
         # Issue #22406
         encodedtext1 = (
@@ -163,8 +159,6 @@ class UUStdIOTest(unittest.TestCase):
         sys.stdin = self.stdin
         sys.stdout = self.stdout
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_encode(self):
         sys.stdin = FakeIO(plaintext.decode("ascii"))
         sys.stdout = FakeIO()
@@ -172,8 +166,6 @@ class UUStdIOTest(unittest.TestCase):
         self.assertEqual(sys.stdout.getvalue(),
                          encodedtextwrapped(0o666, "t1").decode("ascii"))
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_decode(self):
         sys.stdin = FakeIO(encodedtextwrapped(0o666, "t1").decode("ascii"))
         sys.stdout = FakeIO()
@@ -192,8 +184,6 @@ class UUFileTest(unittest.TestCase):
         self.addCleanup(os_helper.unlink, self.tmpin)
         self.addCleanup(os_helper.unlink, self.tmpout)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_encode(self):
         with open(self.tmpin, 'wb') as fin:
             fin.write(plaintext)
@@ -212,8 +202,6 @@ class UUFileTest(unittest.TestCase):
             s = fout.read()
         self.assertEqual(s, encodedtextwrapped(0o644, self.tmpin))
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_decode(self):
         with open(self.tmpin, 'wb') as f:
             f.write(encodedtextwrapped(0o644, self.tmpout))
@@ -226,8 +214,6 @@ class UUFileTest(unittest.TestCase):
         self.assertEqual(s, plaintext)
         # XXX is there an xp way to verify the mode?
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_decode_filename(self):
         with open(self.tmpin, 'wb') as f:
             f.write(encodedtextwrapped(0o644, self.tmpout))

stdlib/src/binascii.rs

@@ -289,7 +289,7 @@ mod decl {
             if [b'\r', b'\n'].contains(c) {
                 return Ok(0);
             }
-            return Err(vm.new_value_error("Illegal char".to_string()));
+            return Err(super::new_binascii_error("Illegal char".to_owned(), vm));
         }
         Ok((*c - b' ') & 0x3f)
     }
@@ -645,7 +645,8 @@ mod decl {
 
             // Allocate the buffer
             let mut res = Vec::<u8>::with_capacity(length);
-            let trailing_garbage_error = || Err(vm.new_value_error("Trailing garbage".to_string()));
+            let trailing_garbage_error =
+                || Err(super::new_binascii_error("Trailing garbage".to_owned(), vm));
 
             for chunk in b.get(1..).unwrap_or_default().chunks(4) {
                 let (char_a, char_b, char_c, char_d) = {
@@ -666,7 +667,7 @@ mod decl {
                 }
 
                 if res.len() < length {
-                    res.push((char_b & 0xf) | char_c >> 2);
+                    res.push((char_b & 0xf) << 4 | char_c >> 2);
                 } else if char_c != 0 {
                     return trailing_garbage_error();
                 }
@@ -688,7 +689,7 @@ mod decl {
 
     #[derive(FromArgs)]
     struct BacktickArg {
-        #[pyarg(named, default = "true")]
+        #[pyarg(named, default = "false")]
         backtick: bool,
     }
 
@@ -700,7 +701,7 @@ mod decl {
     ) -> PyResult<Vec<u8>> {
         #[inline]
         fn uu_b2a(num: u8, backtick: bool) -> u8 {
-            if backtick && num != 0 {
+            if backtick && num == 0 {
                 0x60
             } else {
                 b' ' + num
@@ -710,7 +711,10 @@ mod decl {
         data.with_ref(|b| {
             let length = b.len();
             if length > 45 {
-                return Err(vm.new_value_error("At most 45 bytes at once".to_string()));
+                return Err(super::new_binascii_error(
+                    "At most 45 bytes at once".to_owned(),
+                    vm,
+                ));
             }
             let mut res = Vec::<u8>::with_capacity(2 + ((length + 2) / 3) * 4);
             res.push(uu_b2a(length as u8, backtick));