Add regtest for \tagGroup command

diff --git a/input/regression/tag-group.ly b/input/regression/tag-group.ly
new file mode 100644 (file)
index 0000000..76b0a3f
--- /dev/null
+++ b/input/regression/tag-group.ly
@@ -0,0 +1,78 @@
+\version "2.19.14"
+
+\header {
+  texidoc = "The operation of @code{\\keepWithTag} can be made more
+flexible by using @code{\\tagGroup}."
+}
+
+\layout { ragged-right= ##t }
+
+music =
+<<
+  \tag vI.vII
+  \new Staff \with { instrumentName = "vI vII" }
+  <<
+    \tag vI \new Voice \with { \voiceOne }
+    { g''-\tag slurs ( a'' g'' a''-\tag slurs ) }
+    \tag vII \new Voice \with { \voiceTwo }
+    { c''-\tag slurs ( d'' c'' d''-\tag slurs ) }
+  >>
+  \tag bI.bII
+  \new Staff \with { instrumentName = "bI bII" \clef "bass" }
+  <<
+    \tag bI \new Voice \with { \voiceOne }
+    { g-\tag slurs ( a g a-\tag slurs ) }
+    \tag bII \new Voice \with { \voiceTwo }
+    { c-\tag slurs ( d c d-\tag slurs ) }
+  >>
+>>
+
+demo =
+#(define-music-function (parser location syms m)
+  (symbol-list? ly:music?)
+  #{
+    \new Score <<
+      \keepWithTag #syms #m
+      \context Staff \mark #(string-join (map symbol->string syms) "&")
+    >>
+  #})
+
+#(set-global-staff-size 16)
+
+demoline =
+#(define-scheme-function (parser location m1 m2) (ly:music? ly:music?)
+  #{
+    \markup \column { \fill-line { \null \score { #m1 } \score { #m2 } \null }
+                      \vspace #1 }
+  #})
+
+
+\markuplist {
+  \fill-line { \center-column \fontsize #5 \bold { "\\keepWithTag" } }
+  \vspace #1
+}
+
+\demoline
+\demo #'(vI vII bI bII slurs) \music
+\demo #'(slurs vI) \music
+\demoline
+\demo #'(vI bI bII) \music
+\demo #'(vI bI bII none) \music
+
+\markup \vspace #2
+
+\markuplist {
+  \fill-line { \center-align \fontsize #5 \bold \left-column
+              { "\\tagGroup vI.vII" "\\tagGroup bI.bII" } }
+  \vspace #1
+}
+
+\tagGroup vI.vII
+\tagGroup bI.bII
+
+\demoline
+\demo #'(vI vII bI bII slurs) \music
+\demo #'(slurs vI) \music
+\demoline
+\demo #'(vI bI bII) \music
+\demo #'(vI bI bII none) \music