Let \alterBroken tweak ties again

When tweaking Tie grobs, the music function \alterBroken has
incorrectly rejected them since 2.17.6 as not being spanners.
The method of spanner recognition is at fault: 'span-direction
is not used by TieEvent.

Also, use eqv? instead of eq? for comparison of numbers.

diff --git a/ly/music-functions-init.ly b/ly/music-functions-init.ly
index d7eba42a4b03159d4b14860031596db4930111ff..9fe65613454f9c987b9b3d601b4a7afd3c7f2a17 100644 (file)
--- a/ly/music-functions-init.ly
+++ b/ly/music-functions-init.ly
@@ -104,7 +104,8 @@ a starting spanner event, or a symbol list in the form
 form of a spanner event, @var{property} may also have the form
 @samp{Grob.property} for specifying a directed tweak.")
   (if (ly:music? item)
-      (if (eq? (ly:music-property item 'span-direction) START)
+      (if (or (eqv? (ly:music-property item 'span-direction) START)
+              (music-is-of-type? item 'tie-event))
           (tweak property (value-for-spanner-piece arg) item)
           (begin
             (ly:music-warning item (_ "not a spanner"))