(compose-gstring-for-terminal): If a character is

not supported by the current terminal, don't make a multi-glyph
grapheme cluster.
(auto-compose-chars): Check font-object by fontp.

diff --git a/lisp/composite.el b/lisp/composite.el
index c37a37e..537adab 100644 (file)
--- a/lisp/composite.el
+++ b/lisp/composite.el
@@ -664,28 +664,45 @@ a prepending a space before it."
         (nchars (lgstring-char-len gstring))
         (nglyphs (lgstring-glyph-len gstring))
         (i 0)
+        (coding (lgstring-font gstring))
         glyph)
     (while (and (< i nglyphs)
                (setq glyph (lgstring-glyph gstring i)))
-      (if (= (lglyph-width glyph) 0)
+      (if (not (char-charset (lglyph-char glyph) coding))
          (progn
-           ;; Compose by prepending a space.
-           (setq gstring (lgstring-insert-glyph gstring i (lglyph-copy glyph))
-                 nglyphs (lgstring-glyph-len gstring))
-           (lglyph-set-char (lgstring-glyph gstring i) 32)
-           (setq i (+ 2)))
-       (let ((from (lglyph-from glyph))
-             (to (lglyph-to glyph))
-             (j (1+ i)))
-         (while (and (< j nglyphs)
-                     (setq glyph (lgstring-glyph gstring j))
-                     (= (lglyph-width glyph) 0))
-           (setq to (lglyph-to glyph)
-                 j (1+ j)))
-         (while (< i j)
-           (setq glyph (lgstring-glyph gstring i))
-           (lglyph-set-from-to glyph from to)
-           (setq i (1+ i))))))
+           ;; As the terminal doesn't support this glyph, return a
+           ;; gstring in which each glyph is its own graphme-cluster
+           ;; of width 1..
+           (setq i 0)
+           (while (and (< i nglyphs)
+                       (setq glyph (lgstring-glyph gstring i)))
+             (if (< (lglyph-width glyph) 1)
+                 (lglyph-set-width glyph 1))
+             (lglyph-set-from-to glyph i i)
+             (setq i (1+ i))))
+       (if (= (lglyph-width glyph) 0)
+           (progn
+             ;; Compose by prepending a space.
+             (setq gstring (lgstring-insert-glyph gstring i
+                                                  (lglyph-copy glyph))
+                   nglyphs (lgstring-glyph-len gstring))
+             (setq glyph (lgstring-glyph gstring i))
+             (lglyph-set-char glyph 32)
+             (lglyph-set-width glyph 1)
+             (setq i (+ 2)))
+         (let ((from (lglyph-from glyph))
+               (to (lglyph-to glyph))
+               (j (1+ i)))
+           (while (and (< j nglyphs)
+                       (setq glyph (lgstring-glyph gstring j))
+                       (char-charset (lglyph-char glyph) coding)
+                       (= (lglyph-width glyph) 0))
+             (setq to (lglyph-to glyph)
+                   j (1+ j)))
+           (while (< i j)
+             (setq glyph (lgstring-glyph gstring i))
+             (lglyph-set-from-to glyph from to)
+             (setq i (1+ i)))))))
     gstring))
 
 
@@ -709,7 +726,7 @@ This function is the default value of `auto-composition-function' (which see)."
   (let ((gstring (composition-get-gstring from to font-object string)))
     (if (lgstring-shaped-p gstring)
        gstring
-      (or font-object
+      (or (fontp font-object 'font-object)
          (setq func 'compose-gstring-for-terminal))
       (funcall func gstring))))