Issues #29311, #29289: Fixed and improved docstrings for dict and OrderedDict

methods.

Lib/collections/__init__.py

@@ -157,9 +157,9 @@ class OrderedDict(dict):
         dict.clear(self)
 
     def popitem(self, last=True):
-        '''od.popitem() -> (k, v), return and remove a (key, value) pair.
-        Pairs are returned in LIFO order if last is true or FIFO order if false.
+        '''Remove and return a (key, value) pair from the dictionary.
 
+        Pairs are returned in LIFO order if last is true or FIFO order if false.
         '''
         if not self:
             raise KeyError('dictionary is empty')
@@ -180,11 +180,9 @@ class OrderedDict(dict):
         return key, value
 
     def move_to_end(self, key, last=True):
-        '''Move an existing element to the end (or beginning if last==False).
-
-        Raises KeyError if the element does not exist.
-        When last=True, acts like a fast version of self[key]=self.pop(key).
+        '''Move an existing element to the end (or beginning if last is false).
 
+        Raise KeyError if the element does not exist.
         '''
         link = self.__map[key]
         link_prev = link.prev
@@ -248,7 +246,10 @@ class OrderedDict(dict):
         return default
 
     def setdefault(self, key, default=None):
-        'od.setdefault(k[,d]) -> od.get(k,d), also set od[k]=d if k not in od'
+        '''Insert key with a value of default if key is not in the dictionary.
+
+        Return the value for key if key is in the dictionary, else default.
+        '''
         if key in self:
             return self[key]
         self[key] = default
@@ -274,9 +275,7 @@ class OrderedDict(dict):
 
     @classmethod
     def fromkeys(cls, iterable, value=None):
-        '''OD.fromkeys(S[, v]) -> New ordered dictionary with keys from S.
-        If not specified, the value defaults to None.
-
+        '''Create a new ordered dictionary with keys from iterable and values set to value.
         '''
         self = cls()
         for key in iterable:

Objects/clinic/dictobject.c.h

@@ -6,7 +6,7 @@ PyDoc_STRVAR(dict_fromkeys__doc__,
 "fromkeys($type, iterable, value=None, /)\n"
 "--\n"
 "\n"
-"Returns a new dict with keys from iterable and values equal to value.");
+"Create a new dictionary with keys from iterable and values set to value.");
 
 #define DICT_FROMKEYS_METHODDEF    \
     {"fromkeys", (PyCFunction)dict_fromkeys, METH_FASTCALL|METH_CLASS, dict_fromkeys__doc__},
@@ -40,7 +40,7 @@ PyDoc_STRVAR(dict___contains____doc__,
 "__contains__($self, key, /)\n"
 "--\n"
 "\n"
-"True if D has a key k, else False.");
+"True if the dictionary has a specified key, else False.");
 
 #define DICT___CONTAINS___METHODDEF    \
     {"__contains__", (PyCFunction)dict___contains__, METH_O|METH_COEXIST, dict___contains____doc__},
@@ -49,7 +49,7 @@ PyDoc_STRVAR(dict_get__doc__,
 "get($self, key, default=None, /)\n"
 "--\n"
 "\n"
-"D.get(key[, default]) -> D[key] if key in D, else default.");
+"Return the value for key if key is in the dictionary, else default.");
 
 #define DICT_GET_METHODDEF    \
     {"get", (PyCFunction)dict_get, METH_FASTCALL, dict_get__doc__},
@@ -83,7 +83,9 @@ PyDoc_STRVAR(dict_setdefault__doc__,
 "setdefault($self, key, default=None, /)\n"
 "--\n"
 "\n"
-"D.get(key,default), also set D[key]=default if key not in D.");
+"Insert key with a value of default if key is not in the dictionary.\n"
+"\n"
+"Return the value for key if key is in the dictionary, else default.");
 
 #define DICT_SETDEFAULT_METHODDEF    \
     {"setdefault", (PyCFunction)dict_setdefault, METH_FASTCALL, dict_setdefault__doc__},
@@ -113,4 +115,4 @@ dict_setdefault(PyDictObject *self, PyObject **args, Py_ssize_t nargs, PyObject
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=6e9d917602373072 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=91aa6a9f3c402b1b input=a9049054013a1b77]*/

Objects/clinic/odictobject.c.h

@@ -6,9 +6,7 @@ PyDoc_STRVAR(OrderedDict_fromkeys__doc__,
 "fromkeys($type, /, iterable, value=None)\n"
 "--\n"
 "\n"
-"New ordered dictionary with keys from S.\n"
-"\n"
-"If not specified, the value defaults to None.");
+"Create a new ordered dictionary with keys from iterable and values set to value.");
 
 #define ORDEREDDICT_FROMKEYS_METHODDEF    \
     {"fromkeys", (PyCFunction)OrderedDict_fromkeys, METH_FASTCALL|METH_CLASS, OrderedDict_fromkeys__doc__},
@@ -39,7 +37,9 @@ PyDoc_STRVAR(OrderedDict_setdefault__doc__,
 "setdefault($self, /, key, default=None)\n"
 "--\n"
 "\n"
-"od.get(k,d), also set od[k]=d if k not in od.");
+"Insert key with a value of default if key is not in the dictionary.\n"
+"\n"
+"Return the value for key if key is in the dictionary, else default.");
 
 #define ORDEREDDICT_SETDEFAULT_METHODDEF    \
     {"setdefault", (PyCFunction)OrderedDict_setdefault, METH_FASTCALL, OrderedDict_setdefault__doc__},
@@ -71,7 +71,7 @@ PyDoc_STRVAR(OrderedDict_popitem__doc__,
 "popitem($self, /, last=True)\n"
 "--\n"
 "\n"
-"Return (k, v) and remove a (key, value) pair.\n"
+"Remove and return a (key, value) pair from the dictionary.\n"
 "\n"
 "Pairs are returned in LIFO order if last is true or FIFO order if false.");
 
@@ -103,10 +103,9 @@ PyDoc_STRVAR(OrderedDict_move_to_end__doc__,
 "move_to_end($self, /, key, last=True)\n"
 "--\n"
 "\n"
-"\"Move an existing element to the end (or beginning if last==False).\n"
+"Move an existing element to the end (or beginning if last is false).\n"
 "\n"
-"    Raises KeyError if the element does not exist.\n"
-"    When last=True, acts like a fast version of self[key]=self.pop(key).");
+"Raise KeyError if the element does not exist.");
 
 #define ORDEREDDICT_MOVE_TO_END_METHODDEF    \
     {"move_to_end", (PyCFunction)OrderedDict_move_to_end, METH_FASTCALL, OrderedDict_move_to_end__doc__},
@@ -132,4 +131,4 @@ OrderedDict_move_to_end(PyODictObject *self, PyObject **args, Py_ssize_t nargs,
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=84ef19e7b5db0086 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=a19a24ac37b42e5e input=a9049054013a1b77]*/

Objects/dictobject.c

@@ -2311,12 +2311,12 @@ dict.fromkeys
     value: object=None
     /
 
-Returns a new dict with keys from iterable and values equal to value.
+Create a new dictionary with keys from iterable and values set to value.
 [clinic start generated code]*/
 
 static PyObject *
 dict_fromkeys_impl(PyTypeObject *type, PyObject *iterable, PyObject *value)
-/*[clinic end generated code: output=8fb98e4b10384999 input=b85a667f9bf4669d]*/
+/*[clinic end generated code: output=8fb98e4b10384999 input=382ba4855d0f74c3]*/
 {
     return _PyDict_FromKeys((PyObject *)type, iterable, value);
 }
@@ -2764,12 +2764,12 @@ dict.__contains__
   key: object
   /
 
-True if D has a key k, else False.
+True if the dictionary has the specified key, else False.
 [clinic start generated code]*/
 
 static PyObject *
 dict___contains__(PyDictObject *self, PyObject *key)
-/*[clinic end generated code: output=a3d03db709ed6e6b input=b852b2a19b51ab24]*/
+/*[clinic end generated code: output=a3d03db709ed6e6b input=f39613886bf975b7]*/
 {
     register PyDictObject *mp = self;
     Py_hash_t hash;
@@ -2797,12 +2797,12 @@ dict.get
     default: object = None
     /
 
-D.get(key[, default]) -> D[key] if key in D, else default.
+Return the value for key if key is in the dictionary, else default.
 [clinic start generated code]*/
 
 static PyObject *
 dict_get_impl(PyDictObject *self, PyObject *key, PyObject *default_value)
-/*[clinic end generated code: output=bba707729dee05bf input=e73ab0f028f4b2be]*/
+/*[clinic end generated code: output=bba707729dee05bf input=279ddb5790b6b107]*/
 {
     PyObject *val = NULL;
     Py_hash_t hash;
@@ -2915,13 +2915,15 @@ dict.setdefault
     default: object = None
     /
 
-D.get(key,default), also set D[key]=default if key not in D.
+Insert key with a value of default if key is not in the dictionary.
+
+Return the value for key if key is in the dictionary, else default.
 [clinic start generated code]*/
 
 static PyObject *
 dict_setdefault_impl(PyDictObject *self, PyObject *key,
                      PyObject *default_value)
-/*[clinic end generated code: output=f8c1101ebf69e220 input=b2826255bacd845a]*/
+/*[clinic end generated code: output=f8c1101ebf69e220 input=0f063756e815fd9d]*/
 {
     PyObject *val;
 

Objects/odictobject.c

@@ -926,14 +926,12 @@ OrderedDict.fromkeys
     iterable as seq: object
     value: object = None
 
-New ordered dictionary with keys from S.
-
-If not specified, the value defaults to None.
+Create a new ordered dictionary with keys from iterable and values set to value.
 [clinic start generated code]*/
 
 static PyObject *
 OrderedDict_fromkeys_impl(PyTypeObject *type, PyObject *seq, PyObject *value)
-/*[clinic end generated code: output=c10390d452d78d6d input=33eefc496d5eee7b]*/
+/*[clinic end generated code: output=c10390d452d78d6d input=1a0476c229c597b3]*/
 {
     return _PyDict_FromKeys((PyObject *)type, seq, value);
 }
@@ -1014,13 +1012,15 @@ OrderedDict.setdefault
     key: object
     default: object = None
 
-od.get(k,d), also set od[k]=d if k not in od.
+Insert key with a value of default if key is not in the dictionary.
+
+Return the value for key if key is in the dictionary, else default.
 [clinic start generated code]*/
 
 static PyObject *
 OrderedDict_setdefault_impl(PyODictObject *self, PyObject *key,
                             PyObject *default_value)
-/*[clinic end generated code: output=97537cb7c28464b6 input=d5e940fcea7a5a67]*/
+/*[clinic end generated code: output=97537cb7c28464b6 input=38e098381c1efbc6]*/
 {
     PyObject *result = NULL;
 
@@ -1165,14 +1165,14 @@ OrderedDict.popitem
 
     last: bool = True
 
-Return (k, v) and remove a (key, value) pair.
+Remove and return a (key, value) pair from the dictionary.
 
 Pairs are returned in LIFO order if last is true or FIFO order if false.
 [clinic start generated code]*/
 
 static PyObject *
 OrderedDict_popitem_impl(PyODictObject *self, int last)
-/*[clinic end generated code: output=98e7d986690d49eb input=4937da2015939126]*/
+/*[clinic end generated code: output=98e7d986690d49eb input=d992ac5ee8305e1a]*/
 {
     PyObject *key, *value, *item = NULL;
     _ODictNode *node;
@@ -1324,15 +1324,14 @@ OrderedDict.move_to_end
     key: object
     last: bool = True
 
-"Move an existing element to the end (or beginning if last==False).
+Move an existing element to the end (or beginning if last is false).
 
-    Raises KeyError if the element does not exist.
-    When last=True, acts like a fast version of self[key]=self.pop(key).
+Raise KeyError if the element does not exist.
 [clinic start generated code]*/
 
 static PyObject *
 OrderedDict_move_to_end_impl(PyODictObject *self, PyObject *key, int last)
-/*[clinic end generated code: output=fafa4c5cc9b92f20 input=3b8283f7d0e15e43]*/
+/*[clinic end generated code: output=fafa4c5cc9b92f20 input=d6ceff7132a2fcd7]*/
 {
     _ODictNode *node;