bpo-46852: Rename float.__set_format__() to float.__setformat__() (GH-31558) (GH-31578)

Rename the private undocumented float.__set_format__() method to
float.__setformat__() to fix a typo introduced in Python 3.7. The
method is only used by test_float.

The change enables again test_float tests on the float format which
were previously skipped because of the typo.

The typo was introduced in Python 3.7 by bpo-20185
in commit b5c51d3.

(cherry picked from commit 7d03c8b)

Author: vstinner

Misc/NEWS.d/next/Core and Builtins/2022-02-25-02-01-42.bpo-46852._3zg8D.rst

@@ -0,0 +1,3 @@
+Rename the private undocumented ``float.__set_format__()`` method to
+``float.__setformat__()`` to fix a typo introduced in Python 3.7. The method
+is only used by test_float. Patch by Victor Stinner.

Objects/clinic/floatobject.c.h

@@ -1748,7 +1748,7 @@ float___getformat___impl(PyTypeObject *type, const char *typestr)
 
 /*[clinic input]
 @classmethod
-float.__set_format__
+float.__setformat__
 
     typestr: str
         Must be 'double' or 'float'.
@@ -1767,9 +1767,9 @@ This affects how floats are converted to and from binary strings.
 [clinic start generated code]*/
 
 static PyObject *
-float___set_format___impl(PyTypeObject *type, const char *typestr,
-                          const char *fmt)
-/*[clinic end generated code: output=504460f5dc85acbd input=5306fa2b81a997e4]*/
+float___setformat___impl(PyTypeObject *type, const char *typestr,
+                         const char *fmt)
+/*[clinic end generated code: output=06864de1fb5f1f04 input=c0e9e04dd87f9988]*/
 {
     float_format_type f;
     float_format_type detected;
@@ -1871,7 +1871,7 @@ static PyMethodDef float_methods[] = {
     FLOAT_IS_INTEGER_METHODDEF
     FLOAT___GETNEWARGS___METHODDEF
     FLOAT___GETFORMAT___METHODDEF
-    FLOAT___SET_FORMAT___METHODDEF
+    FLOAT___SETFORMAT___METHODDEF
     FLOAT___FORMAT___METHODDEF
     {NULL,              NULL}           /* sentinel */
 };