[Python-checkins] cpython: Issue #23171: csv.Writer.writerow() now supports arbitrary iterables.
serhiy.storchaka
python-checkins at python.org
Mon Mar 30 08:22:02 CEST 2015
https://hg.python.org/cpython/rev/cf5b62036445
changeset: 95275:cf5b62036445
user: Serhiy Storchaka <storchaka at gmail.com>
date: Mon Mar 30 09:09:54 2015 +0300
summary:
Issue #23171: csv.Writer.writerow() now supports arbitrary iterables.
files:
Doc/library/csv.rst | 4 +-
Lib/csv.py | 7 +--
Lib/test/test_csv.py | 8 +++
Misc/NEWS | 2 +
Modules/_csv.c | 79 +++++++++++++++----------------
5 files changed, 54 insertions(+), 46 deletions(-)
diff --git a/Doc/library/csv.rst b/Doc/library/csv.rst
--- a/Doc/library/csv.rst
+++ b/Doc/library/csv.rst
@@ -419,7 +419,7 @@
:class:`Writer` objects (:class:`DictWriter` instances and objects returned by
the :func:`writer` function) have the following public methods. A *row* must be
-a sequence of strings or numbers for :class:`Writer` objects and a dictionary
+an iterable of strings or numbers for :class:`Writer` objects and a dictionary
mapping fieldnames to strings or numbers (by passing them through :func:`str`
first) for :class:`DictWriter` objects. Note that complex numbers are written
out surrounded by parens. This may cause some problems for other programs which
@@ -431,6 +431,8 @@
Write the *row* parameter to the writer's file object, formatted according to
the current dialect.
+ .. versionchanged:: 3.5
+ Added support of arbitrary iterables.
.. method:: csvwriter.writerows(rows)
diff --git a/Lib/csv.py b/Lib/csv.py
--- a/Lib/csv.py
+++ b/Lib/csv.py
@@ -147,16 +147,13 @@
if wrong_fields:
raise ValueError("dict contains fields not in fieldnames: "
+ ", ".join([repr(x) for x in wrong_fields]))
- return [rowdict.get(key, self.restval) for key in self.fieldnames]
+ return (rowdict.get(key, self.restval) for key in self.fieldnames)
def writerow(self, rowdict):
return self.writer.writerow(self._dict_to_list(rowdict))
def writerows(self, rowdicts):
- rows = []
- for rowdict in rowdicts:
- rows.append(self._dict_to_list(rowdict))
- return self.writer.writerows(rows)
+ return self.writer.writerows(map(self._dict_to_list, rowdicts))
# Guard Sniffer's type checking against builds that exclude complex()
try:
diff --git a/Lib/test/test_csv.py b/Lib/test/test_csv.py
--- a/Lib/test/test_csv.py
+++ b/Lib/test/test_csv.py
@@ -186,6 +186,14 @@
self._write_test(['a',1,'p,q'], 'a,1,p\\,q',
escapechar='\\', quoting = csv.QUOTE_NONE)
+ def test_write_iterable(self):
+ self._write_test(iter(['a', 1, 'p,q']), 'a,1,"p,q"')
+ self._write_test(iter(['a', 1, None]), 'a,1,')
+ self._write_test(iter([]), '')
+ self._write_test(iter([None]), '""')
+ self._write_error_test(csv.Error, iter([None]), quoting=csv.QUOTE_NONE)
+ self._write_test(iter([None, None]), ',')
+
def test_writerows(self):
class BrokenFile:
def write(self, buf):
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -56,6 +56,8 @@
Library
-------
+- Issue #23171: csv.Writer.writerow() now supports arbitrary iterables.
+
- Issue #23745: The new email header parser now handles duplicate MIME
parameter names without error, similar to how get_param behaves.
diff --git a/Modules/_csv.c b/Modules/_csv.c
--- a/Modules/_csv.c
+++ b/Modules/_csv.c
@@ -1009,7 +1009,7 @@
*/
static Py_ssize_t
join_append_data(WriterObj *self, unsigned int field_kind, void *field_data,
- Py_ssize_t field_len, int quote_empty, int *quoted,
+ Py_ssize_t field_len, int *quoted,
int copy_phase)
{
DialectObj *dialect = self->dialect;
@@ -1071,18 +1071,6 @@
ADDCH(c);
}
- /* If field is empty check if it needs to be quoted.
- */
- if (i == 0 && quote_empty) {
- if (dialect->quoting == QUOTE_NONE) {
- PyErr_Format(_csvstate_global->error_obj,
- "single empty field record must be quoted");
- return -1;
- }
- else
- *quoted = 1;
- }
-
if (*quoted) {
if (copy_phase)
ADDCH(dialect->quotechar);
@@ -1126,7 +1114,7 @@
}
static int
-join_append(WriterObj *self, PyObject *field, int *quoted, int quote_empty)
+join_append(WriterObj *self, PyObject *field, int quoted)
{
unsigned int field_kind = -1;
void *field_data = NULL;
@@ -1141,7 +1129,7 @@
field_len = PyUnicode_GET_LENGTH(field);
}
rec_len = join_append_data(self, field_kind, field_data, field_len,
- quote_empty, quoted, 0);
+ "ed, 0);
if (rec_len < 0)
return 0;
@@ -1150,7 +1138,7 @@
return 0;
self->rec_len = join_append_data(self, field_kind, field_data, field_len,
- quote_empty, quoted, 1);
+ "ed, 1);
self->num_fields++;
return 1;
@@ -1181,37 +1169,30 @@
}
PyDoc_STRVAR(csv_writerow_doc,
-"writerow(sequence)\n"
+"writerow(iterable)\n"
"\n"
-"Construct and write a CSV record from a sequence of fields. Non-string\n"
+"Construct and write a CSV record from an iterable of fields. Non-string\n"
"elements will be converted to string.");
static PyObject *
csv_writerow(WriterObj *self, PyObject *seq)
{
DialectObj *dialect = self->dialect;
- Py_ssize_t len, i;
- PyObject *line, *result;
+ PyObject *iter, *field, *line, *result;
- if (!PySequence_Check(seq))
- return PyErr_Format(_csvstate_global->error_obj, "sequence expected");
-
- len = PySequence_Length(seq);
- if (len < 0)
- return NULL;
+ iter = PyObject_GetIter(seq);
+ if (iter == NULL)
+ return PyErr_Format(_csvstate_global->error_obj,
+ "iterable expected, not %.200s",
+ seq->ob_type->tp_name);
/* Join all fields in internal buffer.
*/
join_reset(self);
- for (i = 0; i < len; i++) {
- PyObject *field;
+ while ((field = PyIter_Next(iter))) {
int append_ok;
int quoted;
- field = PySequence_GetItem(seq, i);
- if (field == NULL)
- return NULL;
-
switch (dialect->quoting) {
case QUOTE_NONNUMERIC:
quoted = !PyNumber_Check(field);
@@ -1225,11 +1206,11 @@
}
if (PyUnicode_Check(field)) {
- append_ok = join_append(self, field, "ed, len == 1);
+ append_ok = join_append(self, field, quoted);
Py_DECREF(field);
}
else if (field == Py_None) {
- append_ok = join_append(self, NULL, "ed, len == 1);
+ append_ok = join_append(self, NULL, quoted);
Py_DECREF(field);
}
else {
@@ -1237,19 +1218,37 @@
str = PyObject_Str(field);
Py_DECREF(field);
- if (str == NULL)
+ if (str == NULL) {
+ Py_DECREF(iter);
return NULL;
- append_ok = join_append(self, str, "ed, len == 1);
+ }
+ append_ok = join_append(self, str, quoted);
Py_DECREF(str);
}
- if (!append_ok)
+ if (!append_ok) {
+ Py_DECREF(iter);
+ return NULL;
+ }
+ }
+ Py_DECREF(iter);
+ if (PyErr_Occurred())
+ return NULL;
+
+ if (self->num_fields > 0 && self->rec_size == 0) {
+ if (dialect->quoting == QUOTE_NONE) {
+ PyErr_Format(_csvstate_global->error_obj,
+ "single empty field record must be quoted");
+ return NULL;
+ }
+ self->num_fields--;
+ if (!join_append(self, NULL, 1))
return NULL;
}
/* Add line terminator.
*/
if (!join_append_lineterminator(self))
- return 0;
+ return NULL;
line = PyUnicode_FromKindAndData(PyUnicode_4BYTE_KIND,
(void *) self->rec, self->rec_len);
@@ -1261,9 +1260,9 @@
}
PyDoc_STRVAR(csv_writerows_doc,
-"writerows(sequence of sequences)\n"
+"writerows(iterable of iterables)\n"
"\n"
-"Construct and write a series of sequences to a csv file. Non-string\n"
+"Construct and write a series of iterables to a csv file. Non-string\n"
"elements will be converted to string.");
static PyObject *
--
Repository URL: https://hg.python.org/cpython
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