bpo-40676: Use Argument Clinic for csv (where possible) (GH-20200)

Misc/NEWS.d/next/Library/2020-05-19-01-40-51.bpo-40676.yJfq1J.rst

@@ -0,0 +1,3 @@
+Convert :mod:`csv` to use Argument Clinic for :func:`csv.field_size_limit`,
+:func:`csv.get_dialect`, :func:`csv.unregister_dialect` and :func:`csv.list_dialects`.
+

Modules/_csv.c

@@ -14,6 +14,12 @@ module instead.
 #include "structmember.h"         // PyMemberDef
 #include <stdbool.h>
 
+/*[clinic input]
+module _csv
+[clinic start generated code]*/
+/*[clinic end generated code: output=da39a3ee5e6b4b0d input=385118b71aa43706]*/
+
+#include "clinic/_csv.c.h"
 #define NOT_SET ((Py_UCS4)-1)
 #define EOL ((Py_UCS4)-2)
 
@@ -1473,8 +1479,18 @@ csv_writer(PyObject *module, PyObject *args, PyObject *keyword_args)
 /*
  * DIALECT REGISTRY
  */
+
+/*[clinic input]
+_csv.list_dialects
+
+Return a list of all known dialect names.
+
+    names = csv.list_dialects()
+[clinic start generated code]*/
+
 static PyObject *
-csv_list_dialects(PyObject *module, PyObject *args)
+_csv_list_dialects_impl(PyObject *module)
+/*[clinic end generated code: output=a5b92b215b006a6d input=8953943eb17d98ab]*/
 {
     return PyDict_Keys(get_csv_state(module)->dialects);
 }
@@ -1506,11 +1522,23 @@ csv_register_dialect(PyObject *module, PyObject *args, PyObject *kwargs)
     Py_RETURN_NONE;
 }
 
+
+/*[clinic input]
+_csv.unregister_dialect
+
+    name: object
+
+Delete the name/dialect mapping associated with a string name.
+
+    csv.unregister_dialect(name)
+[clinic start generated code]*/
+
 static PyObject *
-csv_unregister_dialect(PyObject *module, PyObject *name_obj)
+_csv_unregister_dialect_impl(PyObject *module, PyObject *name)
+/*[clinic end generated code: output=0813ebca6c058df4 input=6b5c1557bf60c7e7]*/
 {
     _csvstate *module_state = get_csv_state(module);
-    if (PyDict_DelItem(module_state->dialects, name_obj) < 0) {
+    if (PyDict_DelItem(module_state->dialects, name) < 0) {
         if (PyErr_ExceptionMatches(PyExc_KeyError)) {
             PyErr_Format(module_state->error_obj, "unknown dialect");
         }
@@ -1519,21 +1547,42 @@ csv_unregister_dialect(PyObject *module, PyObject *name_obj)
     Py_RETURN_NONE;
 }
 
+/*[clinic input]
+_csv.get_dialect
+
+    name: object
+
+Return the dialect instance associated with name.
+
+    dialect = csv.get_dialect(name)
+[clinic start generated code]*/
+
 static PyObject *
-csv_get_dialect(PyObject *module, PyObject *name_obj)
+_csv_get_dialect_impl(PyObject *module, PyObject *name)
+/*[clinic end generated code: output=aa988cd573bebebb input=edf9ddab32e448fb]*/
 {
-    return get_dialect_from_registry(name_obj, get_csv_state(module));
+    return get_dialect_from_registry(name, get_csv_state(module));
 }
 
+/*[clinic input]
+_csv.field_size_limit
+
+    new_limit: object = NULL
+
+Sets an upper limit on parsed fields.
+
+    csv.field_size_limit([limit])
+
+Returns old limit. If limit is not given, no new limit is set and
+the old limit is returned
+[clinic start generated code]*/
+
 static PyObject *
-csv_field_size_limit(PyObject *module, PyObject *args)
+_csv_field_size_limit_impl(PyObject *module, PyObject *new_limit)
+/*[clinic end generated code: output=f2799ecd908e250b input=cec70e9226406435]*/
 {
-    PyObject *new_limit = NULL;
     _csvstate *module_state = get_csv_state(module);
     long old_limit = module_state->field_limit;
-
-    if (!PyArg_UnpackTuple(args, "field_size_limit", 0, 1, &new_limit))
-        return NULL;
     if (new_limit != NULL) {
         if (!PyLong_CheckExact(new_limit)) {
             PyErr_Format(PyExc_TypeError,
@@ -1650,44 +1699,21 @@ PyDoc_STRVAR(csv_writer_doc,
 "\n"
 "The \"fileobj\" argument can be any object that supports the file API.\n");
 
-PyDoc_STRVAR(csv_list_dialects_doc,
-"Return a list of all know dialect names.\n"
-"    names = csv.list_dialects()");
-
-PyDoc_STRVAR(csv_get_dialect_doc,
-"Return the dialect instance associated with name.\n"
-"    dialect = csv.get_dialect(name)");
-
 PyDoc_STRVAR(csv_register_dialect_doc,
 "Create a mapping from a string name to a dialect class.\n"
 "    dialect = csv.register_dialect(name[, dialect[, **fmtparams]])");
 
-PyDoc_STRVAR(csv_unregister_dialect_doc,
-"Delete the name/dialect mapping associated with a string name.\n"
-"    csv.unregister_dialect(name)");
-
-PyDoc_STRVAR(csv_field_size_limit_doc,
-"Sets an upper limit on parsed fields.\n"
-"    csv.field_size_limit([limit])\n"
-"\n"
-"Returns old limit. If limit is not given, no new limit is set and\n"
-"the old limit is returned");
-
 static struct PyMethodDef csv_methods[] = {
     { "reader", (PyCFunction)(void(*)(void))csv_reader,
         METH_VARARGS | METH_KEYWORDS, csv_reader_doc},
     { "writer", (PyCFunction)(void(*)(void))csv_writer,
         METH_VARARGS | METH_KEYWORDS, csv_writer_doc},
-    { "list_dialects", (PyCFunction)csv_list_dialects,
-        METH_NOARGS, csv_list_dialects_doc},
     { "register_dialect", (PyCFunction)(void(*)(void))csv_register_dialect,
         METH_VARARGS | METH_KEYWORDS, csv_register_dialect_doc},
-    { "unregister_dialect", (PyCFunction)csv_unregister_dialect,
-        METH_O, csv_unregister_dialect_doc},
-    { "get_dialect", (PyCFunction)csv_get_dialect,
-        METH_O, csv_get_dialect_doc},
-    { "field_size_limit", (PyCFunction)csv_field_size_limit,
-        METH_VARARGS, csv_field_size_limit_doc},
+    _CSV_LIST_DIALECTS_METHODDEF
+    _CSV_UNREGISTER_DIALECT_METHODDEF
+    _CSV_GET_DIALECT_METHODDEF
+    _CSV_FIELD_SIZE_LIMIT_METHODDEF
     { NULL, NULL }
 };
 

Modules/clinic/_csv.c.h

@@ -0,0 +1,134 @@
+/*[clinic input]
+preserve
+[clinic start generated code]*/
+
+PyDoc_STRVAR(_csv_list_dialects__doc__,
+"list_dialects($module, /)\n"
+"--\n"
+"\n"
+"Return a list of all known dialect names.\n"
+"\n"
+"    names = csv.list_dialects()");
+
+#define _CSV_LIST_DIALECTS_METHODDEF    \
+    {"list_dialects", (PyCFunction)_csv_list_dialects, METH_NOARGS, _csv_list_dialects__doc__},
+
+static PyObject *
+_csv_list_dialects_impl(PyObject *module);
+
+static PyObject *
+_csv_list_dialects(PyObject *module, PyObject *Py_UNUSED(ignored))
+{
+    return _csv_list_dialects_impl(module);
+}
+
+PyDoc_STRVAR(_csv_unregister_dialect__doc__,
+"unregister_dialect($module, /, name)\n"
+"--\n"
+"\n"
+"Delete the name/dialect mapping associated with a string name.\n"
+"\n"
+"    csv.unregister_dialect(name)");
+
+#define _CSV_UNREGISTER_DIALECT_METHODDEF    \
+    {"unregister_dialect", (PyCFunction)(void(*)(void))_csv_unregister_dialect, METH_FASTCALL|METH_KEYWORDS, _csv_unregister_dialect__doc__},
+
+static PyObject *
+_csv_unregister_dialect_impl(PyObject *module, PyObject *name);
+
+static PyObject *
+_csv_unregister_dialect(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
+{
+    PyObject *return_value = NULL;
+    static const char * const _keywords[] = {"name", NULL};
+    static _PyArg_Parser _parser = {NULL, _keywords, "unregister_dialect", 0};
+    PyObject *argsbuf[1];
+    PyObject *name;
+
+    args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser, 1, 1, 0, argsbuf);
+    if (!args) {
+        goto exit;
+    }
+    name = args[0];
+    return_value = _csv_unregister_dialect_impl(module, name);
+
+exit:
+    return return_value;
+}
+
+PyDoc_STRVAR(_csv_get_dialect__doc__,
+"get_dialect($module, /, name)\n"
+"--\n"
+"\n"
+"Return the dialect instance associated with name.\n"
+"\n"
+"    dialect = csv.get_dialect(name)");
+
+#define _CSV_GET_DIALECT_METHODDEF    \
+    {"get_dialect", (PyCFunction)(void(*)(void))_csv_get_dialect, METH_FASTCALL|METH_KEYWORDS, _csv_get_dialect__doc__},
+
+static PyObject *
+_csv_get_dialect_impl(PyObject *module, PyObject *name);
+
+static PyObject *
+_csv_get_dialect(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
+{
+    PyObject *return_value = NULL;
+    static const char * const _keywords[] = {"name", NULL};
+    static _PyArg_Parser _parser = {NULL, _keywords, "get_dialect", 0};
+    PyObject *argsbuf[1];
+    PyObject *name;
+
+    args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser, 1, 1, 0, argsbuf);
+    if (!args) {
+        goto exit;
+    }
+    name = args[0];
+    return_value = _csv_get_dialect_impl(module, name);
+
+exit:
+    return return_value;
+}
+
+PyDoc_STRVAR(_csv_field_size_limit__doc__,
+"field_size_limit($module, /, new_limit=<unrepresentable>)\n"
+"--\n"
+"\n"
+"Sets an upper limit on parsed fields.\n"
+"\n"
+"    csv.field_size_limit([limit])\n"
+"\n"
+"Returns old limit. If limit is not given, no new limit is set and\n"
+"the old limit is returned");
+
+#define _CSV_FIELD_SIZE_LIMIT_METHODDEF    \
+    {"field_size_limit", (PyCFunction)(void(*)(void))_csv_field_size_limit, METH_FASTCALL|METH_KEYWORDS, _csv_field_size_limit__doc__},
+
+static PyObject *
+_csv_field_size_limit_impl(PyObject *module, PyObject *new_limit);
+
+static PyObject *
+_csv_field_size_limit(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
+{
+    PyObject *return_value = NULL;
+    static const char * const _keywords[] = {"new_limit", NULL};
+    static _PyArg_Parser _parser = {NULL, _keywords, "field_size_limit", 0};
+    PyObject *argsbuf[1];
+    Py_ssize_t noptargs = nargs + (kwnames ? PyTuple_GET_SIZE(kwnames) : 0) - 0;
+    PyObject *new_limit = NULL;
+
+    args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser, 0, 1, 0, argsbuf);
+    if (!args) {
+        goto exit;
+    }
+    if (!noptargs) {
+        goto skip_optional_pos;
+    }
+    new_limit = args[0];
+skip_optional_pos:
+    return_value = _csv_field_size_limit_impl(module, new_limit);
+
+exit:
+    return return_value;
+}
+/*[clinic end generated code: output=d51f3c42e9b88802 input=a9049054013a1b77]*/