Fix sxhash-equal on bytecodes, markers, etc.

Problem reported by Pip Cet (Bug#38912#14).
* doc/lispref/objects.texi (Equality Predicates):
Document better when ‘equal’ looks inside objects.
* doc/lispref/windows.texi (Window Configurations):
Don’t say that ‘equal’ looks inside window configurations.
* etc/NEWS: Mention the change.
* src/fns.c (internal_equal):
Do not look inside window configurations.
(sxhash_obj): Hash markers, byte-code function objects,
char-tables, and font objects consistently with Fequal.
* src/window.c (compare_window_configurations):
Now static.  Remove last argument.  Caller changed.
* test/lisp/ffap-tests.el (ffap-other-window--bug-25352):
Use compare-window-configurations, not ‘equal’.
* test/src/fns-tests.el (test-sxhash-equal): New test.

1 files changed, 16 insertions, 0 deletions

diff --git a/test/src/fns-tests.el b/test/src/fns-tests.el
index 60be2c6c2d7..c6ceae4a00e 100644
--- a/test/src/fns-tests.el
+++ b/test/src/fns-tests.el
@@ -858,6 +858,22 @@
        (puthash k k h)))
     (should (= 100 (hash-table-count h)))))
 
+(ert-deftest test-sxhash-equal ()
+  (should (= (sxhash-equal (* most-positive-fixnum most-negative-fixnum))
+             (sxhash-equal (* most-positive-fixnum most-negative-fixnum))))
+  (should (= (sxhash-equal (make-string 1000 ?a))
+             (sxhash-equal (make-string 1000 ?a))))
+  (should (= (sxhash-equal (point-marker))
+             (sxhash-equal (point-marker))))
+  (should (= (sxhash-equal (make-vector 1000 (make-string 10 ?a)))
+             (sxhash-equal (make-vector 1000 (make-string 10 ?a)))))
+  (should (= (sxhash-equal (make-bool-vector 1000 t))
+             (sxhash-equal (make-bool-vector 1000 t))))
+  (should (= (sxhash-equal (make-char-table nil (make-string 10 ?a)))
+             (sxhash-equal (make-char-table nil (make-string 10 ?a)))))
+  (should (= (sxhash-equal (record 'a (make-string 10 ?a)))
+             (sxhash-equal (record 'a (make-string 10 ?a))))))
+
 (ert-deftest test-secure-hash ()
   (should (equal (secure-hash 'md5    "foobar")
                  "3858f62230ac3c915f300c664312c63f"))