adds a test for invert_chord and fixes sorting issue

Author: owenniblock

app/server/ruby/lib/sonicpi/lang/western_theory.rb

@@ -1055,7 +1055,7 @@ def chord_invert(notes, shift)
         elsif(shift < 0)
           chord_invert((notes.to_a[0..-2] + [notes.to_a[-1]-12]).sort, shift+1)
         else
-          notes.ring
+          notes.ring.sort
         end
       end
       doc name:          :chord_invert,

app/server/ruby/test/lang/western_theory/test_invert_chord.rb

@@ -38,6 +38,10 @@ def test_inversion_of_basic_major
       # edge case
       assert_equal(Lang::WesternTheory.chord_invert(Lang::WesternTheory.chord(:C4, "1"), 1), [72].ring)
       assert_equal(Lang::WesternTheory.chord_invert(Lang::WesternTheory.chord(:C4, "1"), -1), [48].ring)
+
+       # reported ordering issue: https://github.com/sonic-pi-net/sonic-pi/issues/2779
+       assert_equal(Lang::WesternTheory.chord_invert(Chord.resolve_degree(:i, :C3, :major, 5), 1), [52, 55, 59, 60, 62].ring)
+       assert_equal(Lang::WesternTheory.chord_invert(Chord.resolve_degree(:i, :C3, :major, 5), 2), [55, 59, 60, 62, 64].ring)
     end
 
   end