Issue #5920: Changed format.__float__ and complex.__float__ to use a precision of 12 when using the empty presentation type. This more closely matches str()'s behavior and reduces surprises when adding alignment flags to an empty format string. Patch by Mark Dickinson.

1 files changed, 10 insertions, 5 deletions

diff --git a/Objects/floatobject.c b/Objects/floatobject.c
index 9a0dbb33c2..6b9a310dd3 100644
--- a/Objects/floatobject.c
+++ b/Objects/floatobject.c
@@ -352,7 +352,7 @@ convert_to_double(PyObject **v, double *dbl)
 void
 PyFloat_AsString(char *buf, PyFloatObject *v)
 {
-	_PyOS_double_to_string(buf, 100, v->ob_fval, 's', 0,
+	_PyOS_double_to_string(buf, 100, v->ob_fval, 'g', PyFloat_STR_PRECISION,
 			       Py_DTSF_ADD_DOT_0, NULL);
 }
 
@@ -368,9 +368,13 @@ static int
 float_print(PyFloatObject *v, FILE *fp, int flags)
 {
 	char buf[100];
-	_PyOS_double_to_string(buf, sizeof(buf), v->ob_fval,
-			       (flags & Py_PRINT_RAW) ? 's' : 'r',
-			       0, Py_DTSF_ADD_DOT_0, NULL);
+        if (flags & Py_PRINT_RAW)
+            _PyOS_double_to_string(buf, sizeof(buf), v->ob_fval,
+                                   'g', PyFloat_STR_PRECISION,
+                                   Py_DTSF_ADD_DOT_0, NULL);
+        else
+            _PyOS_double_to_string(buf, sizeof(buf), v->ob_fval,
+                                   'r', 0, Py_DTSF_ADD_DOT_0, NULL);
 	Py_BEGIN_ALLOW_THREADS
 	fputs(buf, fp);
 	Py_END_ALLOW_THREADS
@@ -390,7 +394,8 @@ static PyObject *
 float_str(PyFloatObject *v)
 {
 	char buf[100];
-	_PyOS_double_to_string(buf, sizeof(buf), v->ob_fval, 's', 0,
+	_PyOS_double_to_string(buf, sizeof(buf), v->ob_fval, 'g',
+                               PyFloat_STR_PRECISION,
 			       Py_DTSF_ADD_DOT_0, NULL);
 	return PyString_FromString(buf);
 }