From d3024f0823da8c451f61fb1eabdb9a5850c9ad85 Mon Sep 17 00:00:00 2001
From: Mike Solomon <mike@apollinemike.com>
Date: Mon, 21 Mar 2011 10:20:45 -0400
Subject: [PATCH] Fixes accidental suggestions in the beam collision engraver
 (issue 1570)

Adds an inline-accidental-interface that the engraver uses to filter out
all accidentals that do not come before a note in the staff.
---
 input/regression/beam-collision-accidentals.ly | 12 ++++++++++++
 lily/beam-collision-engraver.cc                |  3 ++-
 scm/define-grob-interfaces.scm                 |  6 ++++++
 scm/define-grobs.scm                           |  2 ++
 4 files changed, 22 insertions(+), 1 deletion(-)
 create mode 100644 input/regression/beam-collision-accidentals.ly

diff --git a/input/regression/beam-collision-accidentals.ly b/input/regression/beam-collision-accidentals.ly
new file mode 100644
index 0000000000..90238f40f4
--- /dev/null
+++ b/input/regression/beam-collision-accidentals.ly
@@ -0,0 +1,12 @@
+\version "2.13.47"
+\header {
+  texidoc = "Beams only check for collisions with in-line accidentals."
+}
+
+{
+ \set suggestAccidentals = ##t
+  a'8[ fis'16 g'16]
+  \unset suggestAccidentals
+  c'8 [ des'' ]
+  r2
+}
\ No newline at end of file
diff --git a/lily/beam-collision-engraver.cc b/lily/beam-collision-engraver.cc
index 39e614c2a1..367570ff6d 100644
--- a/lily/beam-collision-engraver.cc
+++ b/lily/beam-collision-engraver.cc
@@ -160,7 +160,8 @@ Beam_collision_engraver::acknowledge_note_head (Grob_info i)
 void
 Beam_collision_engraver::acknowledge_accidental (Grob_info i)
 {
-  covered_grobs_.push_back (i.grob ());
+  if (i.grob ()->internal_has_interface (ly_symbol2scm ("inline-accidental-interface")))
+    covered_grobs_.push_back (i.grob ());
 }
 
 void
diff --git a/scm/define-grob-interfaces.scm b/scm/define-grob-interfaces.scm
index 223cdafcf6..edc02a7fb3 100644
--- a/scm/define-grob-interfaces.scm
+++ b/scm/define-grob-interfaces.scm
@@ -107,6 +107,12 @@ note)."
  "Keep track of durations in a run of grace notes."
  '(columns common-shortest-duration))
 
+(ly:add-interface
+ 'inline-accidental-interface
+ "An inlined accidental (i.e. normal accidentals, cautionary
+accidentals)."
+ '())
+
 (ly:add-interface
  'instrument-specific-markup-interface
  "Instrument-specific markup (like fret boards or harp pedal diagrams)."
diff --git a/scm/define-grobs.scm b/scm/define-grobs.scm
index 8b9564f41e..a9b2001772 100644
--- a/scm/define-grobs.scm
+++ b/scm/define-grobs.scm
@@ -36,6 +36,7 @@
 	(Y-extent . ,ly:accidental-interface::height)
 	(meta . ((class . Item)
 		 (interfaces . (accidental-interface
+				inline-accidental-interface
 				font-interface))))))
 
     (AccidentalCautionary
@@ -48,6 +49,7 @@
 	(Y-extent . ,ly:accidental-interface::height)
 	(meta . ((class . Item)
 		 (interfaces . (accidental-interface
+				inline-accidental-interface
 				font-interface))))))
 
     (AccidentalPlacement
-- 
2.39.2