gh-106487: Allow the 'count' argument of str.replace to be a keyword

Doc/library/stdtypes.rst

@@ -2014,11 +2014,14 @@ expression support in the :mod:`re` module).
    .. versionadded:: 3.9
 
 
-.. method:: str.replace(old, new[, count])
+.. method:: str.replace(old, new, count=-1)
 
    Return a copy of the string with all occurrences of substring *old* replaced by
-   *new*.  If the optional argument *count* is given, only the first *count*
-   occurrences are replaced.
+   *new*.  If *count* is given, only the first *count* occurrences are replaced.
+   If *count* is not specified or ``-1``, then all occurrences are replaced.
+
+   .. versionchanged:: 3.13
+      *count* is now supported as a keyword argument.
 
 
 .. method:: str.rfind(sub[, start[, end]])

Doc/whatsnew/3.13.rst

@@ -76,7 +76,8 @@ New Features
 Other Language Changes
 ======================
 
-
+* Allow the *count* argument of :meth:`str.replace` to be a keyword.
+  (Contributed by Hugo van Kemenade in :gh:`106487`.)
 
 New Modules
 ===========

Lib/test/string_tests.py

@@ -154,6 +154,12 @@ def test_count(self):
                     self.assertEqual(rem, 0, '%s != 0 for %s' % (rem, i))
                     self.assertEqual(r1, r2, '%s != %s for %s' % (r1, r2, i))
 
+    def test_count_keyword(self):
+        self.assertEqual('aa'.replace('a', 'b', 0), 'aa'.replace('a', 'b', count=0))
+        self.assertEqual('aa'.replace('a', 'b', 1), 'aa'.replace('a', 'b', count=1))
+        self.assertEqual('aa'.replace('a', 'b', 2), 'aa'.replace('a', 'b', count=2))
+        self.assertEqual('aa'.replace('a', 'b', 3), 'aa'.replace('a', 'b', count=3))
+
     def test_find(self):
         self.checkequal(0, 'abcdefghiabc', 'find', 'abc')
         self.checkequal(9, 'abcdefghiabc', 'find', 'abc', 1)

Misc/NEWS.d/next/Core and Builtins/2023-07-06-22-46-05.gh-issue-106487.u3KfAD.rst

@@ -0,0 +1,2 @@
+Allow the *count* argument of :meth:`str.replace` to be a keyword. Patch by
+Hugo van Kemenade.

Objects/unicodeobject.c

@@ -12025,10 +12025,10 @@ str.replace as unicode_replace
 
     old: unicode
     new: unicode
+    /
     count: Py_ssize_t = -1
         Maximum number of occurrences to replace.
         -1 (the default value) means replace all occurrences.
-    /
 
 Return a copy with all occurrences of substring old replaced by new.
 
@@ -12039,7 +12039,7 @@ replaced.
 static PyObject *
 unicode_replace_impl(PyObject *self, PyObject *old, PyObject *new,
                      Py_ssize_t count)
-/*[clinic end generated code: output=b63f1a8b5eebf448 input=147d12206276ebeb]*/
+/*[clinic end generated code: output=b63f1a8b5eebf448 input=3345c455d60a5499]*/
 {
     return replace(self, old, new, count);
 }