[Emacs-diffs] master 53f3dd6 1/2: ffloor etc. now accept only floats

[Paul Eggert]

branch: master
commit 53f3dd66f12660a47018fc03d50d460787ab6f64
Author: Paul Eggert <address@hidden>
Commit: Paul Eggert <address@hidden>

    ffloor etc. now accept only floats
    
    * etc/NEWS: Say why.
    * src/floatfns.c (Ffceiling, Fffloor, Ffround, Fftruncate):
    Require arg to be float.
    * test/src/floatfns-tests.el (fround-fixnum): Check this.
---
 etc/NEWS                   |  6 ++++++
 src/floatfns.c             | 16 ++++++++++------
 test/src/floatfns-tests.el |  6 ++++++
 3 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/etc/NEWS b/etc/NEWS
index fe02236..8f7356f 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -908,6 +908,12 @@ due to internal rounding errors.  For example, (< 
most-positive-fixnum
 (+ 1.0 most-positive-fixnum)) now correctly returns t on 64-bit hosts.
 
 ---
+** The functions 'ffloor', 'fceiling', 'ftruncate' and 'fround' now
+accept only floating-point arguments, as per their documentation.
+Formerly, they quietly accepted integer arguments and sometimes
+returned nonsensical answers, e.g., (< N (ffloor N)) could return t.
+
+---
 ** On hosts like GNU/Linux x86-64 where a 'long double' fraction
 contains at least EMACS_INT_WIDTH - 3 bits, 'format' no longer returns
 incorrect answers due to internal rounding errors when formatting
diff --git a/src/floatfns.c b/src/floatfns.c
index 9ae8106..4c09036 100644
--- a/src/floatfns.c
+++ b/src/floatfns.c
@@ -504,17 +504,19 @@ DEFUN ("fceiling", Ffceiling, Sfceiling, 1, 1, 0,
 \(Round toward +inf.)  */)
   (Lisp_Object arg)
 {
-  double d = extract_float (arg);
+  CHECK_FLOAT (arg);
+  double d = XFLOAT_DATA (arg);
   d = ceil (d);
   return make_float (d);
 }
 
 DEFUN ("ffloor", Fffloor, Sffloor, 1, 1, 0,
        doc: /* Return the largest integer no greater than ARG, as a float.
-\(Round towards -inf.)  */)
+\(Round toward -inf.)  */)
   (Lisp_Object arg)
 {
-  double d = extract_float (arg);
+  CHECK_FLOAT (arg);
+  double d = XFLOAT_DATA (arg);
   d = floor (d);
   return make_float (d);
 }
@@ -523,17 +525,19 @@ DEFUN ("fround", Ffround, Sfround, 1, 1, 0,
        doc: /* Return the nearest integer to ARG, as a float.  */)
   (Lisp_Object arg)
 {
-  double d = extract_float (arg);
+  CHECK_FLOAT (arg);
+  double d = XFLOAT_DATA (arg);
   d = emacs_rint (d);
   return make_float (d);
 }
 
 DEFUN ("ftruncate", Fftruncate, Sftruncate, 1, 1, 0,
        doc: /* Truncate a floating point number to an integral float value.
-Rounds the value toward zero.  */)
+\(Round toward zero.)  */)
   (Lisp_Object arg)
 {
-  double d = extract_float (arg);
+  CHECK_FLOAT (arg);
+  double d = XFLOAT_DATA (arg);
   d = emacs_trunc (d);
   return make_float (d);
 }
diff --git a/test/src/floatfns-tests.el b/test/src/floatfns-tests.el
index cdfb824..de3e443 100644
--- a/test/src/floatfns-tests.el
+++ b/test/src/floatfns-tests.el
@@ -28,4 +28,10 @@
 (ert-deftest logb-extreme-fixnum ()
   (should (= (logb most-negative-fixnum) (1+ (logb most-positive-fixnum)))))
 
+(ert-deftest fround-fixnum ()
+  (should-error (ffloor 0) :type 'wrong-type-argument)
+  (should-error (fceiling 0) :type 'wrong-type-argument)
+  (should-error (ftruncate 0) :type 'wrong-type-argument)
+  (should-error (fround 0) :type 'wrong-type-argument))
+
 (provide 'floatfns-tests)