Issue #28217: Adds _testconsole module to test console input. Fixes some issues found by the tests.

Author: zooba

Lib/test/test_winconsoleio.py

@@ -1,12 +1,4 @@
 '''Tests for WindowsConsoleIO
-
-Unfortunately, most testing requires interactive use, since we have no
-API to read back from a real console, and this class is only for use
-with real consoles.
-
-Instead, we validate that basic functionality such as opening, closing
-and in particular fileno() work, but are forced to leave real testing
-to real people with real keyborads.
 '''
 
 import io
@@ -16,6 +8,8 @@
 if sys.platform != 'win32':
     raise unittest.SkipTest("test only relevant on win32")
 
+from _testconsole import write_input
+
 ConIO = io._WindowsConsoleIO
 
 class WindowsConsoleIOTests(unittest.TestCase):
@@ -83,5 +77,65 @@ def test_open_name(self):
         f.close()
         f.close()
 
+    def assertStdinRoundTrip(self, text):
+        stdin = open('CONIN$', 'r')
+        old_stdin = sys.stdin
+        try:
+            sys.stdin = stdin
+            write_input(
+                stdin.buffer.raw,
+                (text + '\r\n').encode('utf-16-le', 'surrogatepass')
+            )
+            actual = input()
+        finally:
+            sys.stdin = old_stdin
+        self.assertEqual(actual, text)
+
+    def test_input(self):
+        # ASCII
+        self.assertStdinRoundTrip('abc123')
+        # Non-ASCII
+        self.assertStdinRoundTrip('ϼўТλФЙ')
+        # Combining characters
+        self.assertStdinRoundTrip('A͏B ﬖ̳AA̝')
+        # Non-BMP
+        self.assertStdinRoundTrip('\U00100000\U0010ffff\U0010fffd')
+
+    def test_partial_reads(self):
+        # Test that reading less than 1 full character works when stdin
+        # contains multibyte UTF-8 sequences
+        source = 'ϼўТλФЙ\r\n'.encode('utf-16-le')
+        expected = 'ϼўТλФЙ\r\n'.encode('utf-8')
+        for read_count in range(1, 16):
+            stdin = open('CONIN$', 'rb', buffering=0)
+            write_input(stdin, source)
+
+            actual = b''
+            while not actual.endswith(b'\n'):
+                b = stdin.read(read_count)
+                actual += b
+
+            self.assertEqual(actual, expected, 'stdin.read({})'.format(read_count))
+            stdin.close()
+
+    def test_partial_surrogate_reads(self):
+        # Test that reading less than 1 full character works when stdin
+        # contains surrogate pairs that cannot be decoded to UTF-8 without
+        # reading an extra character.
+        source = '\U00101FFF\U00101001\r\n'.encode('utf-16-le')
+        expected = '\U00101FFF\U00101001\r\n'.encode('utf-8')
+        for read_count in range(1, 16):
+            stdin = open('CONIN$', 'rb', buffering=0)
+            write_input(stdin, source)
+
+            actual = b''
+            while not actual.endswith(b'\n'):
+                b = stdin.read(read_count)
+                actual += b
+
+            self.assertEqual(actual, expected, 'stdin.read({})'.format(read_count))
+            stdin.close()
+
+
 if __name__ == "__main__":
     unittest.main()

Misc/NEWS

@@ -186,6 +186,10 @@ Build
 - Issue #15819: Remove redundant include search directory option for building
   outside the source tree.
 
+Tests
+-----
+
+- Issue #28217: Adds _testconsole module to test console input.
 
 What's New in Python 3.6.0 beta 1
 =================================

Modules/_io/_iomodule.h

@@ -22,7 +22,8 @@ extern PyTypeObject PyIncrementalNewlineDecoder_Type;
 #ifndef Py_LIMITED_API
 #ifdef MS_WINDOWS
 extern PyTypeObject PyWindowsConsoleIO_Type;
-#define PyWindowsConsoleIO_Check(op) (PyObject_TypeCheck((op), &PyWindowsConsoleIO_Type))
+PyAPI_DATA(PyObject *) _PyWindowsConsoleIO_Type;
+#define PyWindowsConsoleIO_Check(op) (PyObject_TypeCheck((op), (PyTypeObject*)_PyWindowsConsoleIO_Type))
 #endif /* MS_WINDOWS */
 #endif /* Py_LIMITED_API */
 

Modules/_io/winconsoleio.c

@@ -39,6 +39,11 @@
 /* BUFMAX determines how many bytes can be read in one go. */
 #define BUFMAX (32*1024*1024)
 
+/* SMALLBUF determines how many utf-8 characters will be
+   buffered within the stream, in order to support reads
+   of less than one character */
+#define SMALLBUF 4
+
 char _get_console_type(HANDLE handle) {
     DWORD mode, peek_count;
 
@@ -125,7 +130,8 @@ typedef struct {
     unsigned int blksize;
     PyObject *weakreflist;
     PyObject *dict;
-    char buf[4];
+    char buf[SMALLBUF];
+    wchar_t wbuf;
 } winconsoleio;
 
 PyTypeObject PyWindowsConsoleIO_Type;
@@ -500,11 +506,11 @@ _io__WindowsConsoleIO_writable_impl(winconsoleio *self)
 static DWORD
 _buflen(winconsoleio *self)
 {
-    for (DWORD i = 0; i < 4; ++i) {
+    for (DWORD i = 0; i < SMALLBUF; ++i) {
         if (!self->buf[i])
             return i;
     }
-    return 4;
+    return SMALLBUF;
 }
 
 static DWORD
@@ -513,12 +519,10 @@ _copyfrombuf(winconsoleio *self, char *buf, DWORD len)
     DWORD n = 0;
 
     while (self->buf[0] && len--) {
-        n += 1;
-        buf[0] = self->buf[0];
-        self->buf[0] = self->buf[1];
-        self->buf[1] = self->buf[2];
-        self->buf[2] = self->buf[3];
-        self->buf[3] = 0;
+        buf[n++] = self->buf[0];
+        for (int i = 1; i < SMALLBUF; ++i)
+            self->buf[i - 1] = self->buf[i];
+        self->buf[SMALLBUF - 1] = 0;
     }
 
     return n;
@@ -531,10 +535,13 @@ read_console_w(HANDLE handle, DWORD maxlen, DWORD *readlen) {
     wchar_t *buf = (wchar_t*)PyMem_Malloc(maxlen * sizeof(wchar_t));
     if (!buf)
         goto error;
+
     *readlen = 0;
 
+    //DebugBreak();
     Py_BEGIN_ALLOW_THREADS
-    for (DWORD off = 0; off < maxlen; off += BUFSIZ) {
+    DWORD off = 0;
+    while (off < maxlen) {
         DWORD n, len = min(maxlen - off, BUFSIZ);
         SetLastError(0);
         BOOL res = ReadConsoleW(handle, &buf[off], len, &n, NULL);
@@ -550,7 +557,7 @@ read_console_w(HANDLE handle, DWORD maxlen, DWORD *readlen) {
             err = 0;
             HANDLE hInterruptEvent = _PyOS_SigintEvent();
             if (WaitForSingleObjectEx(hInterruptEvent, 100, FALSE)
-                == WAIT_OBJECT_0) {
+                    == WAIT_OBJECT_0) {
                 ResetEvent(hInterruptEvent);
                 Py_BLOCK_THREADS
                 sig = PyErr_CheckSignals();
@@ -568,7 +575,30 @@ read_console_w(HANDLE handle, DWORD maxlen, DWORD *readlen) {
         /* If the buffer ended with a newline, break out */
         if (buf[*readlen - 1] == '\n')
             break;
+        /* If the buffer ends with a high surrogate, expand the
+           buffer and read an extra character. */
+        WORD char_type;
+        if (off + BUFSIZ >= maxlen &&
+            GetStringTypeW(CT_CTYPE3, &buf[*readlen - 1], 1, &char_type) &&
+            char_type == C3_HIGHSURROGATE) {
+            wchar_t *newbuf;
+            maxlen += 1;
+            Py_BLOCK_THREADS
+            newbuf = (wchar_t*)PyMem_Realloc(buf, maxlen * sizeof(wchar_t));
+            Py_UNBLOCK_THREADS
+            if (!newbuf) {
+                sig = -1;
+                break;
+            }
+            buf = newbuf;
+            /* Only advance by n and not BUFSIZ in this case */
+            off += n;
+            continue;
+        }
+
+        off += BUFSIZ;
     }
+
     Py_END_ALLOW_THREADS
 
     if (sig)
@@ -1110,4 +1140,6 @@ PyTypeObject PyWindowsConsoleIO_Type = {
     0,                                          /* tp_finalize */
 };
 
+PyAPI_DATA(PyObject *) _PyWindowsConsoleIO_Type = (PyObject*)&PyWindowsConsoleIO_Type;
+
 #endif /* MS_WINDOWS */

PC/_testconsole.c

@@ -0,0 +1,131 @@
+
+/* Testing module for multi-phase initialization of extension modules (PEP 489)
+ */
+
+#include "Python.h"
+
+#ifdef MS_WINDOWS
+
+#include "..\modules\_io\_iomodule.h"
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <fcntl.h>
+
+ /* The full definition is in iomodule. We reproduce
+ enough here to get the handle, which is all we want. */
+typedef struct {
+    PyObject_HEAD
+    HANDLE handle;
+} winconsoleio;
+
+
+static int execfunc(PyObject *m)
+{
+    return 0;
+}
+
+PyModuleDef_Slot testconsole_slots[] = {
+    {Py_mod_exec, execfunc},
+    {0, NULL},
+};
+
+/*[clinic input]
+module _testconsole
+
+_testconsole.write_input
+    file: object
+    s: PyBytesObject
+
+Writes UTF-16-LE encoded bytes to the console as if typed by a user.
+[clinic start generated code]*/
+
+static PyObject *
+_testconsole_write_input_impl(PyObject *module, PyObject *file,
+                              PyBytesObject *s)
+/*[clinic end generated code: output=48f9563db34aedb3 input=4c774f2d05770bc6]*/
+{
+    INPUT_RECORD *rec = NULL;
+    
+    if (!PyWindowsConsoleIO_Check(file)) {
+        PyErr_SetString(PyExc_TypeError, "expected raw console object");
+        return NULL;
+    }
+
+    const wchar_t *p = (const wchar_t *)PyBytes_AS_STRING(s);
+    DWORD size = (DWORD)PyBytes_GET_SIZE(s) / sizeof(wchar_t);
+
+    rec = (INPUT_RECORD*)PyMem_Malloc(sizeof(INPUT_RECORD) * size);
+    if (!rec)
+        goto error;
+    memset(rec, 0, sizeof(INPUT_RECORD) * size);
+    
+    INPUT_RECORD *prec = rec;
+    for (DWORD i = 0; i < size; ++i, ++p, ++prec) {
+        prec->EventType = KEY_EVENT;
+        prec->Event.KeyEvent.bKeyDown = TRUE;
+        prec->Event.KeyEvent.wRepeatCount = 10;
+        prec->Event.KeyEvent.uChar.UnicodeChar = *p;
+    }
+
+    HANDLE hInput = ((winconsoleio*)file)->handle;
+    DWORD total = 0;
+    while (total < size) {
+        DWORD wrote;
+        if (!WriteConsoleInputW(hInput, &rec[total], (size - total), &wrote)) {
+            PyErr_SetFromWindowsErr(0);
+            goto error;
+        }
+        total += wrote;
+    }
+
+    PyMem_Free((void*)rec);
+    
+    Py_RETURN_NONE;
+error:
+    if (rec)
+        PyMem_Free((void*)rec);
+    return NULL;
+}
+
+/*[clinic input]
+_testconsole.read_output
+    file: object
+
+Reads a str from the console as written to stdout.
+[clinic start generated code]*/
+
+static PyObject *
+_testconsole_read_output_impl(PyObject *module, PyObject *file)
+/*[clinic end generated code: output=876310d81a73e6d2 input=b3521f64b1b558e3]*/
+{
+    Py_RETURN_NONE;
+}
+
+#include "clinic\_testconsole.c.h"
+
+PyMethodDef testconsole_methods[] = {
+    _TESTCONSOLE_WRITE_INPUT_METHODDEF
+    _TESTCONSOLE_READ_OUTPUT_METHODDEF
+    {NULL, NULL}
+};
+
+static PyModuleDef testconsole_def = {
+    PyModuleDef_HEAD_INIT,                      /* m_base */
+    "_testconsole",                             /* m_name */
+    PyDoc_STR("Test module for the Windows console"), /* m_doc */
+    0,                                          /* m_size */
+    testconsole_methods,                        /* m_methods */
+    testconsole_slots,                          /* m_slots */
+    NULL,                                       /* m_traverse */
+    NULL,                                       /* m_clear */
+    NULL,                                       /* m_free */
+};
+
+PyMODINIT_FUNC
+PyInit__testconsole(PyObject *spec)
+{
+    return PyModuleDef_Init(&testconsole_def);
+}
+
+#endif /* MS_WINDOWS */