Add regtest for extratoken pop_state interference.

diff --git a/input/regression/extratoken.ly b/input/regression/extratoken.ly
new file mode 100644 (file)
index 0000000..754b1f5
--- /dev/null
+++ b/input/regression/extratoken.ly
@@ -0,0 +1,20 @@
+\header {
+  texidoc = "A mode switching command like @code{\\lyricsto} will
+`pop state' when seeing the lookahead token @code{\\time}, a music
+function, after its non-delimited argument.  This must not cause the
+extra token parsing state for the music function to disappear."
+}
+
+\paper {
+  ragged-right = ##t
+}
+
+\version "2.15.31"
+
+x=\lyrics { oh }
+
+<< 
+  \new Voice = m { c'4 r r }
+  \lyricsto "m" \x
+  \time 3/4
+>>