compat-31: Add evenp and oddp

See https://github.com/emacs-compat/compat/issues/63.

3 files changed, 52 insertions, 1 deletions

diff --git a/compat-31.el b/compat-31.el
index cd519c6..cdd79a7 100644
--- a/compat-31.el
+++ b/compat-31.el
@@ -27,6 +27,15 @@
 ;; TODO Update to 31.1 as soon as the Emacs emacs-31 branch version bumped
 (compat-version "31.0.50")
 
+;;;; Defined in subr.el
+
+(compat-defun oddp (integer)
+  "Return t if INTEGER is odd."
+  (not (eq (% integer 2) 0)))
+
+(compat-defun evenp (integer)
+  "Return t if INTEGER is even."
+  (eq (% integer 2) 0))
 
 (provide 'compat-31)
 ;;; compat-31.el ends here
diff --git a/compat-tests.el b/compat-tests.el
index 223d0dd..3b52d0d 100644
--- a/compat-tests.el
+++ b/compat-tests.el
@@ -3254,5 +3254,37 @@
         (trusted-content '("compat-tests.el")))
     (should-not (trusted-content-p))))
 
+(ert-deftest compat-oddp ()
+  (should (oddp 1))
+  (should (oddp -1))
+  (should (oddp 3))
+  (should (oddp most-positive-fixnum))
+  (when (fboundp 'bignump)
+    (should (oddp (+ most-positive-fixnum 2))))
+  (should-not (oddp 0))
+  (should-not (oddp -2))
+  (should-not (oddp 10))
+  (should-not (oddp (1- most-positive-fixnum)))
+  (when (fboundp 'bignump)
+    (should-not (oddp (1+ most-positive-fixnum))))
+  (should-error (oddp 1.0))
+  (should-error (oddp 0.0)))
+
+(ert-deftest compat-evenp ()
+  (should (evenp 0))
+  (should (evenp -2))
+  (should (evenp 10))
+  (should (evenp (1- most-positive-fixnum)))
+  (when (fboundp 'bignump)
+    (should (evenp (1+ most-positive-fixnum))))
+  (should-not (evenp 1))
+  (should-not (evenp -1))
+  (should-not (evenp 3))
+  (should-not (evenp most-positive-fixnum))
+  (when (fboundp 'bignump)
+    (should-not (evenp (+ most-positive-fixnum 2))))
+  (should-error (evenp 1.0))
+  (should-error (evenp 0.0)))
+
 (provide 'compat-tests)
 ;;; compat-tests.el ends here
diff --git a/compat.texi b/compat.texi
index 2743071..51472ce 100644
--- a/compat.texi
+++ b/compat.texi
@@ -3698,7 +3698,17 @@ older than 31.1.  Note that due to upstream changes, it might happen
 that there will be the need for changes, so use these functions with
 care.
 
-@c Placeholder
+@c copied from lispref/numbers.texi
+@defun oddp integer
+This predicate tests whether its argument is an odd number, and returns
+@code{t} if so, @code{nil} otherwise.  The argument must be an integer.
+@end defun
+
+@c copied from lispref/numbers.texi
+@defun evenp integer
+This predicate tests whether its argument is an even number, and returns
+@code{t} if so, @code{nil} otherwise.  The argument must be an integer.
+@end defun
 
 @subsection Extended Definitions
 These functions must be called explicitly via @code{compat-call},