Fix copying text properties in 'format'

* src/editfns.c (styled_format): Fix accounting for text
properties that come from the format string.  (Bug#46317)

* test/src/editfns-tests.el (format-properties): Add new tests for
bug#46317.

2 files changed, 30 insertions, 2 deletions

diff --git a/src/editfns.c b/src/editfns.c
index e3285494c14..991f79abac7 100644
--- a/src/editfns.c
+++ b/src/editfns.c
@@ -3134,6 +3134,7 @@ styled_format (ptrdiff_t nargs, Lisp_Object *args, bool message)
   char *format_start = SSDATA (args[0]);
   bool multibyte_format = STRING_MULTIBYTE (args[0]);
   ptrdiff_t formatlen = SBYTES (args[0]);
+  bool fmt_props = string_intervals (args[0]);
 
   /* Upper bound on number of format specs.  Each uses at least 2 chars.  */
   ptrdiff_t nspec_bound = SCHARS (args[0]) >> 1;
@@ -3406,13 +3407,20 @@ styled_format (ptrdiff_t nargs, Lisp_Object *args, bool message)
               convbytes += padding;
               if (convbytes <= buf + bufsize - p)
                 {
+                  /* If the format spec has properties, we should account
+                     for the padding on the left in the info[] array.  */
+                  if (fmt_props)
+                    spec->start = nchars;
                   if (! minus_flag)
                     {
                       memset (p, ' ', padding);
                       p += padding;
                       nchars += padding;
                     }
-                  spec->start = nchars;
+                  /* If the properties will come from the argument, we
+                     don't extend them to the left due to padding.  */
+                  if (!fmt_props)
+                    spec->start = nchars;
 
                   if (p > buf
                       && multibyte
diff --git a/test/src/editfns-tests.el b/test/src/editfns-tests.el
index 64f9137865b..dcec971c12e 100644
--- a/test/src/editfns-tests.el
+++ b/test/src/editfns-tests.el
@@ -106,7 +106,27 @@
            #("foobar" 3 6 (face error))))
   (should (ert-equal-including-properties
            (format (concat "%s " (propertize "%s" 'face 'error)) "foo" "bar")
-           #("foo bar" 4 7 (face error)))))
+           #("foo bar" 4 7 (face error))))
+  ;; Bug #46317
+  (let ((s (propertize "X" 'prop "val")))
+    (should (ert-equal-including-properties
+             (format (concat "%3s/" s) 12)
+             #(" 12/X" 4 5 (prop "val"))))
+    (should (ert-equal-including-properties
+             (format (concat "%3S/" s) 12)
+             #(" 12/X" 4 5 (prop "val"))))
+    (should (ert-equal-including-properties
+             (format (concat "%3d/" s) 12)
+             #(" 12/X" 4 5 (prop "val"))))
+    (should (ert-equal-including-properties
+             (format (concat "%-3s/" s) 12)
+             #("12 /X" 4 5 (prop "val"))))
+    (should (ert-equal-including-properties
+             (format (concat "%-3S/" s) 12)
+             #("12 /X" 4 5 (prop "val"))))
+    (should (ert-equal-including-properties
+             (format (concat "%-3d/" s) 12)
+             #("12 /X" 4 5 (prop "val"))))))
 
 ;; Tests for bug#5131.
 (defun transpose-test-reverse-word (start end)