[pull] main from python:main

Include/internal/pycore_bytesobject.h

@@ -147,6 +147,15 @@ PyAPI_FUNC(void*) _PyBytesWriter_WriteBytes(_PyBytesWriter *writer,
 PyAPI_FUNC(PyBytesWriter*) _PyBytesWriter_CreateByteArray(
     Py_ssize_t size);
 
+
+struct PyBytesWriter {
+    char small_buffer[256];
+    PyObject *obj;
+    Py_ssize_t size;
+    int use_bytearray;
+    int overallocate;
+};
+
 #ifdef __cplusplus
 }
 #endif

Lib/_pydatetime.py

@@ -1072,7 +1072,11 @@ def fromisocalendar(cls, year, week, day):
 
     @classmethod
     def strptime(cls, date_string, format):
-        """Parse string according to the given date format (like time.strptime())."""
+        """Parse string according to the given date format (like time.strptime()).
+
+        For a list of supported format codes, see the documentation:
+            https://docs.python.org/3/library/datetime.html#format-codes
+        """
         import _strptime
         return _strptime._strptime_datetime_date(cls, date_string, format)
 
@@ -1109,6 +1113,8 @@ def strftime(self, format):
         Format using strftime().
 
         Example: "%d/%m/%Y, %H:%M:%S"
+        For a list of supported format codes, see the documentation:
+            https://docs.python.org/3/library/datetime.html#format-codes
         """
         return _wrap_strftime(self, format, self.timetuple())
 
@@ -1456,8 +1462,13 @@ def __new__(cls, hour=0, minute=0, second=0, microsecond=0, tzinfo=None, *, fold
         return self
 
     @classmethod
+
     def strptime(cls, date_string, format):
-        """Parse string according to the given time format (like time.strptime())."""
+        """Parse string according to the given time format (like time.strptime()).
+
+        For a list of supported format codes, see the documentation:
+            https://docs.python.org/3/library/datetime.html#format-codes
+        """
         import _strptime
         return _strptime._strptime_datetime_time(cls, date_string, format)
 
@@ -1650,6 +1661,9 @@ def fromisoformat(cls, time_string):
     def strftime(self, format):
         """Format using strftime().  The date part of the timestamp passed
         to underlying strftime should not be used.
+
+        For a list of supported format codes, see the documentation:
+            https://docs.python.org/3/library/datetime.html#format-codes
         """
         # The year must be >= 1000 else Python's strftime implementation
         # can raise a bogus exception.
@@ -2198,7 +2212,11 @@ def __str__(self):
 
     @classmethod
     def strptime(cls, date_string, format):
-        """Parse string according to the given date and time format (like time.strptime())."""
+        """Parse string according to the given time format (like time.strptime()).
+
+        For a list of supported format codes, see the documentation:
+            https://docs.python.org/3/library/datetime.html#format-codes
+        """
         import _strptime
         return _strptime._strptime_datetime_datetime(cls, date_string, format)
 

Modules/_datetimemodule.c

@@ -3468,12 +3468,15 @@ datetime.date.strptime
     /
 
 Parse string according to the given date format (like time.strptime()).
+
+For a list of supported format codes, see the documentation:
+    https://docs.python.org/3/library/datetime.html#format-codes
 [clinic start generated code]*/
 
 static PyObject *
 datetime_date_strptime_impl(PyTypeObject *type, PyObject *string,
                             PyObject *format)
-/*[clinic end generated code: output=454d473bee2d5161 input=001904ab34f594a1]*/
+/*[clinic end generated code: output=454d473bee2d5161 input=31d57bb789433e99]*/
 {
     PyObject *result;
 
@@ -3608,11 +3611,14 @@ datetime.date.strftime
 Format using strftime().
 
 Example: "%d/%m/%Y, %H:%M:%S".
+
+For a list of supported format codes, see the documentation:
+    https://docs.python.org/3/library/datetime.html#format-codes
 [clinic start generated code]*/
 
 static PyObject *
 datetime_date_strftime_impl(PyObject *self, PyObject *format)
-/*[clinic end generated code: output=6529b70095e16778 input=72af55077e606ed8]*/
+/*[clinic end generated code: output=6529b70095e16778 input=b6fd4a2ded27b557]*/
 {
     /* This method can be inherited, and needs to call the
      * timetuple() method appropriate to self's class.
@@ -4711,12 +4717,15 @@ datetime.time.strptime
     /
 
 Parse string according to the given time format (like time.strptime()).
+
+For a list of supported format codes, see the documentation:
+    https://docs.python.org/3/library/datetime.html#format-codes
 [clinic start generated code]*/
 
 static PyObject *
 datetime_time_strptime_impl(PyTypeObject *type, PyObject *string,
                             PyObject *format)
-/*[clinic end generated code: output=ae05a9bc0241d3bf input=6d0f263a5f94d78d]*/
+/*[clinic end generated code: output=ae05a9bc0241d3bf input=82ba425ecacc54aa]*/
 {
     PyObject *result;
 
@@ -4891,11 +4900,14 @@ datetime.time.strftime
 Format using strftime().
 
 The date part of the timestamp passed to underlying strftime should not be used.
+
+For a list of supported format codes, see the documentation:
+    https://docs.python.org/3/library/datetime.html#format-codes
 [clinic start generated code]*/
 
 static PyObject *
 datetime_time_strftime_impl(PyDateTime_Time *self, PyObject *format)
-/*[clinic end generated code: output=10f65af20e2a78c7 input=541934a2860f7db5]*/
+/*[clinic end generated code: output=10f65af20e2a78c7 input=c4a5bbecd798654b]*/
 {
     PyObject *result;
     PyObject *tuple;
@@ -5787,12 +5799,15 @@ datetime.datetime.strptime
     /
 
 Parse string according to the given date and time format (like time.strptime()).
+
+For a list of supported format codes, see the documentation:
+    https://docs.python.org/3/library/datetime.html#format-codes
 [clinic start generated code]*/
 
 static PyObject *
 datetime_datetime_strptime_impl(PyTypeObject *type, PyObject *string,
                                 PyObject *format)
-/*[clinic end generated code: output=af2c2d024f3203f5 input=d7597c7f5327117b]*/
+/*[clinic end generated code: output=af2c2d024f3203f5 input=ef7807589f1d50e7]*/
 {
     PyObject *result;
 

Modules/_io/bufferedio.c

@@ -1026,58 +1026,60 @@ static PyObject *
 _io__Buffered_read1_impl(buffered *self, Py_ssize_t n)
 /*[clinic end generated code: output=bcc4fb4e54d103a3 input=3d0ad241aa52b36c]*/
 {
-    Py_ssize_t have, r;
-    PyObject *res = NULL;
-
     CHECK_INITIALIZED(self)
     if (n < 0) {
         n = self->buffer_size;
     }
 
     CHECK_CLOSED(self, "read of closed file")
 
-    if (n == 0)
-        return PyBytes_FromStringAndSize(NULL, 0);
+    if (n == 0) {
+        return Py_GetConstant(Py_CONSTANT_EMPTY_BYTES);
+    }
 
     /* Return up to n bytes.  If at least one byte is buffered, we
        only return buffered bytes.  Otherwise, we do one raw read. */
 
-    have = Py_SAFE_DOWNCAST(READAHEAD(self), Py_off_t, Py_ssize_t);
+    Py_ssize_t have = Py_SAFE_DOWNCAST(READAHEAD(self), Py_off_t, Py_ssize_t);
     if (have > 0) {
         n = Py_MIN(have, n);
-        res = _bufferedreader_read_fast(self, n);
+        PyObject *res = _bufferedreader_read_fast(self, n);
         assert(res != Py_None);
         return res;
     }
-    res = PyBytes_FromStringAndSize(NULL, n);
-    if (res == NULL)
-        return NULL;
+
     if (!ENTER_BUFFERED(self)) {
-        Py_DECREF(res);
         return NULL;
     }
+
     /* Flush the write buffer if necessary */
     if (self->writable) {
-        PyObject *r = buffered_flush_and_rewind_unlocked(self);
-        if (r == NULL) {
+        PyObject *res = buffered_flush_and_rewind_unlocked(self);
+        if (res == NULL) {
             LEAVE_BUFFERED(self)
-            Py_DECREF(res);
             return NULL;
         }
-        Py_DECREF(r);
+        Py_DECREF(res);
     }
     _bufferedreader_reset_buf(self);
-    r = _bufferedreader_raw_read(self, PyBytes_AS_STRING(res), n);
+
+    PyBytesWriter *writer = PyBytesWriter_Create(n);
+    if (writer == NULL) {
+        return NULL;
+    }
+
+    Py_ssize_t r = _bufferedreader_raw_read(self,
+                                            PyBytesWriter_GetData(writer), n);
     LEAVE_BUFFERED(self)
     if (r == -1) {
-        Py_DECREF(res);
+        PyBytesWriter_Discard(writer);
         return NULL;
     }
-    if (r == -2)
+    if (r == -2) {
         r = 0;
-    if (n > r)
-        _PyBytes_Resize(&res, r);
-    return res;
+    }
+
+    return PyBytesWriter_FinishWithSize(writer, r);
 }
 
 static PyObject *

Modules/_io/fileio.c

@@ -739,7 +739,7 @@ _io_FileIO_readall_impl(fileio *self)
 /*[clinic end generated code: output=faa0292b213b4022 input=10d8b2ec403302dc]*/
 {
     Py_off_t pos, end;
-    PyObject *result;
+    PyBytesWriter *writer;
     Py_ssize_t bytes_read = 0;
     Py_ssize_t n;
     size_t bufsize;
@@ -794,10 +794,10 @@ _io_FileIO_readall_impl(fileio *self)
         }
     }
 
-
-    result = PyBytes_FromStringAndSize(NULL, bufsize);
-    if (result == NULL)
+    writer = PyBytesWriter_Create(bufsize);
+    if (writer == NULL) {
         return NULL;
+    }
 
     while (1) {
         if (bytes_read >= (Py_ssize_t)bufsize) {
@@ -806,18 +806,18 @@ _io_FileIO_readall_impl(fileio *self)
                 PyErr_SetString(PyExc_OverflowError,
                                 "unbounded read returned more bytes "
                                 "than a Python bytes object can hold");
-                Py_DECREF(result);
+                PyBytesWriter_Discard(writer);
                 return NULL;
             }
 
-            if (PyBytes_GET_SIZE(result) < (Py_ssize_t)bufsize) {
-                if (_PyBytes_Resize(&result, bufsize) < 0)
+            if (PyBytesWriter_GetSize(writer) < (Py_ssize_t)bufsize) {
+                if (PyBytesWriter_Resize(writer, bufsize) < 0)
                     return NULL;
             }
         }
 
         n = _Py_read(self->fd,
-                     PyBytes_AS_STRING(result) + bytes_read,
+                     (char*)PyBytesWriter_GetData(writer) + bytes_read,
                      bufsize - bytes_read);
 
         if (n == 0)
@@ -827,20 +827,16 @@ _io_FileIO_readall_impl(fileio *self)
                 PyErr_Clear();
                 if (bytes_read > 0)
                     break;
-                Py_DECREF(result);
+                PyBytesWriter_Discard(writer);
                 Py_RETURN_NONE;
             }
-            Py_DECREF(result);
+            PyBytesWriter_Discard(writer);
             return NULL;
         }
         bytes_read += n;
     }
 
-    if (PyBytes_GET_SIZE(result) > bytes_read) {
-        if (_PyBytes_Resize(&result, bytes_read) < 0)
-            return NULL;
-    }
-    return result;
+    return PyBytesWriter_FinishWithSize(writer, bytes_read);
 }
 
 /*[clinic input]
@@ -866,10 +862,6 @@ static PyObject *
 _io_FileIO_read_impl(fileio *self, PyTypeObject *cls, Py_ssize_t size)
 /*[clinic end generated code: output=bbd749c7c224143e input=752d1ad3db8564a5]*/
 {
-    char *ptr;
-    Py_ssize_t n;
-    PyObject *bytes;
-
     if (self->fd < 0)
         return err_closed();
     if (!self->readable) {
@@ -884,31 +876,25 @@ _io_FileIO_read_impl(fileio *self, PyTypeObject *cls, Py_ssize_t size)
         size = _PY_READ_MAX;
     }
 
-    bytes = PyBytes_FromStringAndSize(NULL, size);
-    if (bytes == NULL)
+    PyBytesWriter *writer = PyBytesWriter_Create(size);
+    if (writer == NULL) {
         return NULL;
-    ptr = PyBytes_AS_STRING(bytes);
+    }
+    char *ptr = PyBytesWriter_GetData(writer);
 
-    n = _Py_read(self->fd, ptr, size);
+    Py_ssize_t n = _Py_read(self->fd, ptr, size);
     if (n == -1) {
-        /* copy errno because Py_DECREF() can indirectly modify it */
+        // copy errno because PyBytesWriter_Discard() can indirectly modify it
         int err = errno;
-        Py_DECREF(bytes);
+        PyBytesWriter_Discard(writer);
         if (err == EAGAIN) {
             PyErr_Clear();
             Py_RETURN_NONE;
         }
         return NULL;
     }
 
-    if (n != size) {
-        if (_PyBytes_Resize(&bytes, n) < 0) {
-            Py_CLEAR(bytes);
-            return NULL;
-        }
-    }
-
-    return (PyObject *) bytes;
+    return PyBytesWriter_FinishWithSize(writer, n);
 }
 
 /*[clinic input]