Yet another fix for copying properties by 'format'

* src/textprop.c (extend_property_ranges): Accept an additional
argument OLD_END, and only extend the end of a property range if
its original end is at OLD_END; all the other ranges are left
intact.  (Bug#23897)
* src/editfns.c (styled_format): Pass the original length of the
string to 'extend_property_ranges'.
* src/intervals.h (extend_property_ranges): Adjust prototype.

* test/src/editfns-tests.el (format-properties): Add tests for
bug#23897.

1 files changed, 11 insertions, 1 deletions

diff --git a/test/src/editfns-tests.el b/test/src/editfns-tests.el
index c515927cff1..62d7bc4f5be 100644
--- a/test/src/editfns-tests.el
+++ b/test/src/editfns-tests.el
@@ -54,4 +54,14 @@
   ;; Bug #23859
   (should (ert-equal-including-properties
            (format "%4s" (propertize "hi" 'face 'bold))
-           #("  hi" 0 4 (face bold)))))
+           #("  hi" 0 4 (face bold))))
+
+  ;; Bug #23897
+  (should (ert-equal-including-properties
+           (format "%s" (concat (propertize "01234" 'face 'bold) "56789"))
+           #("0123456789" 0 5 (face bold))))
+  (should (ert-equal-including-properties
+           (format "%s" (concat (propertize "01" 'face 'bold)
+                                (propertize "23" 'face 'underline)
+                                "45"))
+           #("012345" 0 2 (face bold) 2 4 (face underline)))))