https://github.com/python/cpython/commit/6d209cbb93d0871ad4a5883637a8f0aebc053f76 commit: 6d209cbb93d0871ad4a5883637a8f0aebc053f76 branch: main author: mdehoon <[email protected]> committer: serhiy-storchaka <[email protected]> date: 2026-06-29T08:42:56Z summary:
gh-140146: Fix for stdin redirection to a pipe with interactive tkinter on Windows (GH-148819) files: A Lib/test/test_tkinter/test_tkinter_pipe.py A Misc/NEWS.d/next/Windows/2026-04-21-16-07-11.gh-issue-140146.TAcUHA.rst M Modules/_tkinter.c diff --git a/Lib/test/test_tkinter/test_tkinter_pipe.py b/Lib/test/test_tkinter/test_tkinter_pipe.py new file mode 100644 index 000000000000000..775d0ff5e19b0ce --- /dev/null +++ b/Lib/test/test_tkinter/test_tkinter_pipe.py @@ -0,0 +1,55 @@ +# test_tkinter_pipe.py +import unittest +import subprocess +import sys +from test import support + + [email protected](support.has_subprocess_support, "test requires subprocess") +class TkinterPipeTest(unittest.TestCase): + + def test_tkinter_pipe_buffered(self): + args = [sys.executable, "-i"] + proc = subprocess.Popen(args, + stdin=subprocess.PIPE, + stdout=subprocess.PIPE, + stderr=subprocess.PIPE) + proc.stdin.write(b"import tkinter\n") + proc.stdin.write(b"interpreter = tkinter.Tcl()\n") + proc.stdin.write(b"print('hello')\n") + proc.stdin.write(b"print('goodbye')\n") + proc.stdin.write(b"quit()\n") + stdout, stderr = proc.communicate(timeout=support.SHORT_TIMEOUT) + stdout = stdout.decode() + self.assertEqual(stdout.split(), ['hello', 'goodbye']) + + def test_tkinter_pipe_unbuffered(self): + args = [sys.executable, "-i", "-u"] + proc = subprocess.Popen(args, + stdin=subprocess.PIPE, + stdout=subprocess.PIPE, + stderr=subprocess.PIPE) + proc.stdin.write(b"import tkinter\n") + proc.stdin.write(b"interpreter = tkinter.Tcl()\n") + + proc.stdin.write(b"print('hello')\n") + proc.stdin.flush() + stdout = proc.stdout.readline() + stdout = stdout.decode() + self.assertEqual(stdout.strip(), 'hello') + + proc.stdin.write(b"print('hello again')\n") + proc.stdin.flush() + stdout = proc.stdout.readline() + stdout = stdout.decode() + self.assertEqual(stdout.strip(), 'hello again') + + proc.stdin.write(b"print('goodbye')\n") + proc.stdin.write(b"quit()\n") + stdout, stderr = proc.communicate(timeout=support.SHORT_TIMEOUT) + stdout = stdout.decode() + self.assertEqual(stdout.strip(), 'goodbye') + + +if __name__ == "__main__": + unittest.main() diff --git a/Misc/NEWS.d/next/Windows/2026-04-21-16-07-11.gh-issue-140146.TAcUHA.rst b/Misc/NEWS.d/next/Windows/2026-04-21-16-07-11.gh-issue-140146.TAcUHA.rst new file mode 100644 index 000000000000000..2d3e42c86fd521f --- /dev/null +++ b/Misc/NEWS.d/next/Windows/2026-04-21-16-07-11.gh-issue-140146.TAcUHA.rst @@ -0,0 +1,3 @@ +Prevent :mod:`tkinter` from hanging on Windows if stdin is redirected to a pipe in an +interactive session. This is helpful for testing interactive usage of +tkinter from a script, for example as part of the cpython test suite. diff --git a/Modules/_tkinter.c b/Modules/_tkinter.c index 1f1fe4a91addf4c..62a79128d9726ca 100644 --- a/Modules/_tkinter.c +++ b/Modules/_tkinter.c @@ -3443,10 +3443,10 @@ static PyMethodDef moduleMethods[] = }; #ifdef WAIT_FOR_STDIN +#ifndef MS_WINDOWS static int stdin_ready = 0; -#ifndef MS_WINDOWS static void MyFileProc(void *clientData, int mask) { @@ -3465,22 +3465,40 @@ static PyThreadState *event_tstate = NULL; static int EventHook(void) { -#ifndef MS_WINDOWS +#ifdef MS_WINDOWS + HANDLE hStdin; + DWORD type; +#else int tfile; + stdin_ready = 0; #endif PyEval_RestoreThread(event_tstate); - stdin_ready = 0; errorInCmd = 0; -#ifndef MS_WINDOWS +#ifdef MS_WINDOWS + hStdin = GetStdHandle(STD_INPUT_HANDLE); + type = GetFileType(hStdin); + while (1) { +#else tfile = fileno(stdin); Tcl_CreateFileHandler(tfile, TCL_READABLE, MyFileProc, (void *)(Py_intptr_t)tfile); -#endif while (!stdin_ready) { +#endif int result; #ifdef MS_WINDOWS - if (_kbhit()) { - stdin_ready = 1; + if (type == FILE_TYPE_CHAR) { + if (_kbhit()) break; + } + else if (type == FILE_TYPE_PIPE) { + DWORD available; + if (PeekNamedPipe(hStdin, NULL, 0, NULL, &available, NULL)) { + if (available > 0) break; + } + else { + if (GetLastError() == ERROR_BROKEN_PIPE) break; + } + } + else if (type == FILE_TYPE_DISK) { break; } #endif _______________________________________________ Python-checkins mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3//lists/python-checkins.python.org Member address: [email protected]
