Issue1395: Universal mode used to duplicate newlines when using read(1).

"Universal newline" is now an incremental decoder wrapping the initial one,
with its own additional buffer (if '\r' is seen at the end of the input).

A decoder allows the tell() funtion to record the state of the translation.
This also simplifies the readline() process.

Now test_netrc passes on Windows, as well as many new tests in test_io.py

Lib/test/test_io.py

@@ -489,6 +489,10 @@ class BufferedRandomTest(unittest.TestCase):
 
 class TextIOWrapperTest(unittest.TestCase):
 
+    def setUp(self):
+        self.testdata = b"AAA\r\nBBB\rCCC\r\nDDD\nEEE\r\n"
+        self.normalized = b"AAA\nBBB\nCCC\nDDD\nEEE\n".decode("ascii")
+
     def tearDown(self):
         test_support.unlink(test_support.TESTFN)
 
@@ -496,14 +500,14 @@ class TextIOWrapperTest(unittest.TestCase):
         testdata = b"AAA\nBBB\nCCC\rDDD\rEEE\r\nFFF\r\nGGG"
         normalized = testdata.replace(b"\r\n", b"\n").replace(b"\r", b"\n")
         for newline, expected in [
-            (None, normalized.decode("ASCII").splitlines(True)),
-            ("", testdata.decode("ASCII").splitlines(True)),
+            (None, normalized.decode("ascii").splitlines(True)),
+            ("", testdata.decode("ascii").splitlines(True)),
             ("\n", ["AAA\n", "BBB\n", "CCC\rDDD\rEEE\r\n", "FFF\r\n", "GGG"]),
             ("\r\n", ["AAA\nBBB\nCCC\rDDD\rEEE\r\n", "FFF\r\n", "GGG"]),
             ("\r",  ["AAA\nBBB\nCCC\r", "DDD\r", "EEE\r", "\nFFF\r", "\nGGG"]),
             ]:
             buf = io.BytesIO(testdata)
-            txt = io.TextIOWrapper(buf, encoding="ASCII", newline=newline)
+            txt = io.TextIOWrapper(buf, encoding="ascii", newline=newline)
             self.assertEquals(txt.readlines(), expected)
             txt.seek(0)
             self.assertEquals(txt.read(), "".join(expected))
@@ -518,7 +522,7 @@ class TextIOWrapperTest(unittest.TestCase):
         tests = [(None, testdict[os.linesep])] + sorted(testdict.items())
         for newline, expected in tests:
             buf = io.BytesIO()
-            txt = io.TextIOWrapper(buf, encoding="ASCII", newline=newline)
+            txt = io.TextIOWrapper(buf, encoding="ascii", newline=newline)
             txt.write("AAA\nB")
             txt.write("BB\nCCC\n")
             txt.write("X\rY\r\nZ")
@@ -568,14 +572,14 @@ class TextIOWrapperTest(unittest.TestCase):
         testdata = b"AAA\nBBB\nCCC\rDDD\rEEE\r\nFFF\r\nGGG"
         normalized = testdata.replace(b"\r\n", b"\n").replace(b"\r", b"\n")
         for newline, expected in [
-            (None, normalized.decode("ASCII").splitlines(True)),
-            ("", testdata.decode("ASCII").splitlines(True)),
+            (None, normalized.decode("ascii").splitlines(True)),
+            ("", testdata.decode("ascii").splitlines(True)),
             ("\n", ["AAA\n", "BBB\n", "CCC\rDDD\rEEE\r\n", "FFF\r\n", "GGG"]),
             ("\r\n", ["AAA\nBBB\nCCC\rDDD\rEEE\r\n", "FFF\r\n", "GGG"]),
             ("\r",  ["AAA\nBBB\nCCC\r", "DDD\r", "EEE\r", "\nFFF\r", "\nGGG"]),
             ]:
             buf = io.BytesIO(testdata)
-            txt = io.TextIOWrapper(buf, encoding="ASCII", newline=newline)
+            txt = io.TextIOWrapper(buf, encoding="ascii", newline=newline)
             self.assertEquals(txt.readlines(), expected)
             txt.seek(0)
             self.assertEquals(txt.read(), "".join(expected))
@@ -600,7 +604,7 @@ class TextIOWrapperTest(unittest.TestCase):
                 ("\r\n", "\r\n", data_crlf),
                 ]:
                 buf = io.BytesIO()
-                txt = io.TextIOWrapper(buf, encoding="ASCII", newline=newline)
+                txt = io.TextIOWrapper(buf, encoding="ascii", newline=newline)
                 txt.write(data)
                 txt.close()
                 self.assertEquals(buf.getvalue(), expected)
@@ -745,6 +749,114 @@ class TextIOWrapperTest(unittest.TestCase):
                 print("Reading using readline(): %6.3f seconds" % (t3-t2))
                 print("Using readline()+tell():  %6.3f seconds" % (t4-t3))
 
+    def testReadOneByOne(self):
+        txt = io.TextIOWrapper(io.BytesIO(b"AA\r\nBB"))
+        reads = ""
+        while True:
+            c = txt.read(1)
+            if not c:
+                break
+            reads += c
+        self.assertEquals(reads, "AA\nBB")
+
+    # read in amounts equal to TextIOWrapper._CHUNK_SIZE which is 128.
+    def testReadByChunk(self):
+        # make sure "\r\n" straddles 128 char boundary.
+        txt = io.TextIOWrapper(io.BytesIO(b"A" * 127 + b"\r\nB"))
+        reads = ""
+        while True:
+            c = txt.read(128)
+            if not c:
+                break
+            reads += c
+        self.assertEquals(reads, "A"*127+"\nB")
+
+    def test_issue1395_1(self):
+        txt = io.TextIOWrapper(io.BytesIO(self.testdata), encoding="ascii")
+
+        # read one char at a time
+        reads = ""
+        while True:
+            c = txt.read(1)
+            if not c:
+                break
+            reads += c
+        self.assertEquals(reads, self.normalized)
+
+    def test_issue1395_2(self):
+        txt = io.TextIOWrapper(io.BytesIO(self.testdata), encoding="ascii")
+        txt._CHUNK_SIZE = 4
+
+        reads = ""
+        while True:
+            c = txt.read(4)
+            if not c:
+                break
+            reads += c
+        self.assertEquals(reads, self.normalized)
+
+    def test_issue1395_3(self):
+        txt = io.TextIOWrapper(io.BytesIO(self.testdata), encoding="ascii")
+        txt._CHUNK_SIZE = 4
+
+        reads = txt.read(4)
+        reads += txt.read(4)
+        reads += txt.readline()
+        reads += txt.readline()
+        reads += txt.readline()
+        self.assertEquals(reads, self.normalized)
+
+    def test_issue1395_4(self):
+        txt = io.TextIOWrapper(io.BytesIO(self.testdata), encoding="ascii")
+        txt._CHUNK_SIZE = 4
+
+        reads = txt.read(4)
+        reads += txt.read()
+        self.assertEquals(reads, self.normalized)
+
+    def test_issue1395_5(self):
+        txt = io.TextIOWrapper(io.BytesIO(self.testdata), encoding="ascii")
+        txt._CHUNK_SIZE = 4
+
+        reads = txt.read(4)
+        pos = txt.tell()
+        txt.seek(0)
+        txt.seek(pos)
+        self.assertEquals(txt.read(4), "BBB\n")
+
+    def test_newline_decoder(self):
+        import codecs
+        decoder = codecs.getincrementaldecoder("utf-8")()
+        decoder = io.IncrementalNewlineDecoder(decoder, translate=True)
+
+        self.assertEquals(decoder.decode(b'\xe8\xa2\x88'), "\u8888")
+
+        self.assertEquals(decoder.decode(b'\xe8'), "")
+        self.assertEquals(decoder.decode(b'\xa2'), "")
+        self.assertEquals(decoder.decode(b'\x88'), "\u8888")
+
+        self.assertEquals(decoder.decode(b'\xe8'), "")
+        self.assertRaises(UnicodeDecodeError, decoder.decode, b'', final=True)
+
+        decoder.setstate((b'', 0))
+        self.assertEquals(decoder.decode(b'\n'), "\n")
+        self.assertEquals(decoder.decode(b'\r'), "")
+        self.assertEquals(decoder.decode(b'', final=True), "\n")
+        self.assertEquals(decoder.decode(b'\r', final=True), "\n")
+
+        self.assertEquals(decoder.decode(b'\r'), "")
+        self.assertEquals(decoder.decode(b'a'), "\na")
+
+        self.assertEquals(decoder.decode(b'\r\r\n'), "\n\n")
+        self.assertEquals(decoder.decode(b'\r'), "")
+        self.assertEquals(decoder.decode(b'\r'), "\n")
+        self.assertEquals(decoder.decode(b'\na'), "\na")
+
+        self.assertEquals(decoder.decode(b'\xe8\xa2\x88\r\n'), "\u8888\n")
+        self.assertEquals(decoder.decode(b'\xe8\xa2\x88'), "\u8888")
+        self.assertEquals(decoder.decode(b'\n'), "\n")
+        self.assertEquals(decoder.decode(b'\xe8\xa2\x88\r'), "\u8888")
+        self.assertEquals(decoder.decode(b'\n'), "\n")
 
 # XXX Tests for open()
 

Modules/_fileio.c

@@ -867,7 +867,7 @@ static PyGetSetDef fileio_getsetlist[] = {
 
 PyTypeObject PyFileIO_Type = {
 	PyVarObject_HEAD_INIT(&PyType_Type, 0)
-	"FileIO",
+	"_FileIO",
 	sizeof(PyFileIOObject),
 	0,
 	(destructor)fileio_dealloc,		/* tp_dealloc */