Several fixes for formatting bignums

* src/bignum.c: Include stdlib.h, for abs.
(bignum_bufsize, bignum_to_c_string): New functions.
* src/bignum.c (bignum_to_string):
* src/print.c (print_vectorlike): Use them.
* src/editfns.c (styled_format): Instead of having a separate
buffer for sprintf (which does not work for bignums), just append
to the main buffer.  When formatting bignums, add support for the
standard integer flags -, #, 0, + and space.  Fix some comments.
Capitalize properly when formatting bignums with %X.  Use
functions like c_isdigit rather than reinventing the wheel.
Simplify computation of excess precision.
* src/print.c: Do not include bignum.h; no longer needed.
(print_vectorlike): Avoid recalculating string length.
* test/src/editfns-tests.el (format-bignum):
Test some of the above fixes.

1 files changed, 15 insertions, 2 deletions

diff --git a/test/src/editfns-tests.el b/test/src/editfns-tests.el
index 964ff088360..487f3aaa666 100644
--- a/test/src/editfns-tests.el
+++ b/test/src/editfns-tests.el
@@ -381,10 +381,23 @@
   (let* ((s1 "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF")
          (v1 (read (concat "#x" s1)))
          (s2 "99999999999999999999999999999999")
-         (v2 (read s2)))
+         (v2 (read s2))
+         (v3 #x-3ffffffffffffffe000000000000000))
     (should (> v1 most-positive-fixnum))
     (should (equal (format "%X" v1) s1))
     (should (> v2 most-positive-fixnum))
-    (should (equal (format "%d" v2) s2))))
+    (should (equal (format "%d" v2) s2))
+    (should (equal (format "%d" v3) "-5316911983139663489309385231907684352"))
+    (should (equal (format "%+d" v3) "-5316911983139663489309385231907684352"))
+    (should (equal (format "%+d" (- v3))
+                   "+5316911983139663489309385231907684352"))
+    (should (equal (format "% d" (- v3))
+                   " 5316911983139663489309385231907684352"))
+    (should (equal (format "%o" v3)
+                   "-37777777777777777777600000000000000000000"))
+    (should (equal (format "%#50.40x" v3)
+                   "        -0x000000003ffffffffffffffe000000000000000"))
+    (should (equal (format "%-#50.40x" v3)
+                   "-0x000000003ffffffffffffffe000000000000000        "))))
 
 ;;; editfns-tests.el ends here