bpo-39674: Revert "bpo-37330: open() no longer accept 'U' in file mode (GH-16959)" by vstinner · Pull Request #18767 · python/cpython

Expand Up @@ -138,6 +138,7 @@ Character Meaning 'b' binary mode 't' text mode (default) '+' open a disk file for updating (reading and writing) 'U' universal newline mode (deprecated) ========= ===============================================================
The default mode is 'rt' (open for reading text). For binary random Expand All @@ -153,6 +154,10 @@ bytes objects without any decoding. In text mode (the default, or when returned as strings, the bytes having been first decoded using a platform-dependent encoding or using the specified encoding if given.
'U' mode is deprecated and will raise an exception in future versions of Python. It has no effect in Python 3. Use newline to control universal newlines mode.
buffering is an optional integer used to set the buffering policy. Pass 0 to switch buffering off (only allowed in binary mode), 1 to select line buffering (only usable in text mode), and an integer > 1 to indicate Expand Down Expand Up @@ -228,12 +233,12 @@ static PyObject * _io_open_impl(PyObject *module, PyObject *file, const char *mode, int buffering, const char *encoding, const char *errors, const char *newline, int closefd, PyObject *opener) /*[clinic end generated code: output=aefafc4ce2b46dc0 input=1543f4511d2356a5]*/ /*[clinic end generated code: output=aefafc4ce2b46dc0 input=7295902222e6b311]*/ { unsigned i;
int creating = 0, reading = 0, writing = 0, appending = 0, updating = 0; int text = 0, binary = 0; int text = 0, binary = 0, universal = 0;
char rawmode[6], *m; int line_buffering, is_number; Expand Down Expand Up @@ -291,6 +296,10 @@ _io_open_impl(PyObject *module, PyObject *file, const char *mode, case 'b': binary = 1; break; case 'U': universal = 1; reading = 1; break; default: goto invalid_mode; } Expand All @@ -313,6 +322,18 @@ _io_open_impl(PyObject *module, PyObject *file, const char *mode, *m = '\0';
/* Parameters validation */ if (universal) { if (creating || writing || appending || updating) { PyErr_SetString(PyExc_ValueError, "mode U cannot be combined with 'x', 'w', 'a', or '+'"); goto error; } if (PyErr_WarnEx(PyExc_DeprecationWarning, "'U' mode is deprecated", 1) < 0) goto error; reading = 1; }
if (text && binary) { PyErr_SetString(PyExc_ValueError, "can't have text and binary mode at once"); Expand Down