master 988f45a: Fix printing of hash tables with removed elements

[Lars Ingebrigtsen]

branch: master
commit 988f45a75b745dc1fee6315749ddb48f00b000eb
Author: Pip Cet <pipcet@gmail.com>
Commit: Lars Ingebrigtsen <larsi@gnus.org>

    Fix printing of hash tables with removed elements
    
    * src/print.c (print_vectorlike): Keep track of the actual number
    of elements printed rather than attempting to use hash bucket
    indices (bug#38892).
---
 src/print.c             | 17 ++++++++++++-----
 test/src/print-tests.el | 28 ++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+), 5 deletions(-)

diff --git a/src/print.c b/src/print.c
index bd17691..0ecc98f 100644
--- a/src/print.c
+++ b/src/print.c
@@ -1590,27 +1590,34 @@ print_vectorlike (Lisp_Object obj, Lisp_Object 
printcharfun, bool escapeflag,
 
        /* Print the data here as a plist. */
        ptrdiff_t real_size = HASH_TABLE_SIZE (h);
-       ptrdiff_t size = real_size;
+       ptrdiff_t size = h->count;
 
        /* Don't print more elements than the specified maximum.  */
        if (FIXNATP (Vprint_length) && XFIXNAT (Vprint_length) < size)
          size = XFIXNAT (Vprint_length);
 
        printchar ('(', printcharfun);
-       for (ptrdiff_t i = 0; i < size; i++)
+       ptrdiff_t j = 0;
+       for (ptrdiff_t i = 0; i < real_size; i++)
           {
             Lisp_Object key = HASH_KEY (h, i);
            if (!EQ (key, Qunbound))
              {
-               if (i) printchar (' ', printcharfun);
+               if (j++) printchar (' ', printcharfun);
                print_object (key, printcharfun, escapeflag);
                printchar (' ', printcharfun);
                print_object (HASH_VALUE (h, i), printcharfun, escapeflag);
+               if (j == size)
+                 break;
              }
           }
 
-       if (size < real_size)
-         print_c_string (" ...", printcharfun);
+       if (j < h->count)
+         {
+           if (j)
+             printchar (' ', printcharfun);
+           print_c_string ("...", printcharfun);
+         }
 
        print_c_string ("))", printcharfun);
       }
diff --git a/test/src/print-tests.el b/test/src/print-tests.el
index 42e5962..51ef16d 100644
--- a/test/src/print-tests.el
+++ b/test/src/print-tests.el
@@ -355,5 +355,33 @@ otherwise, use a different charset."
     (setcdr err err)
     (should-error (error-message-string err) :type 'circular-list)))
 
+(print-tests--deftest print-hash-table-test ()
+  (should
+   (string-match
+    "data (2 3)"
+    (let ((h (make-hash-table)))
+      (puthash 1 2 h)
+      (puthash 2 3 h)
+      (remhash 1 h)
+      (format "%S" h))))
+
+  (should
+   (string-match
+    "data ()"
+    (let ((h (make-hash-table)))
+      (let ((print-length 0))
+        (format "%S" h)))))
+
+  (should
+   (string-match
+    "data (99 99"
+    (let ((h (make-hash-table)))
+      (dotimes (i 100)
+        (puthash i i h))
+      (dotimes (i 99)
+        (remhash i h))
+      (let ((print-length 1))
+        (format "%S" h))))))
+
 (provide 'print-tests)
 ;;; print-tests.el ends here