autoroute: a Master on a Bluetooth sink is not dangling

Linking it to the default speaker as well would leak the whole set into the room
when monitoring on a headset.

tools/tests/test_autoroute_master_and_control.py

@@ -152,3 +152,16 @@ def test_a_link_to_the_wrong_track_does_not_count(tmp_path):
     wrong = "SuperCollider:out_1\n  |-> ardour:Tidal 02/audio_in 1\n"
     calls, _ = _reconcile(tmp_path, CTRL_LINKED + MASTER_ON_SPEAKER + wrong)
     assert "SuperCollider:out_1 ardour:Tidal 01/audio_in 1" in calls
+
+
+BT_SINK = "bluez_output.70_26_05_D0_D5_90.1"
+MASTER_ON_BOSE = (f"ardour:Master/audio_out 1\n  |-> {BT_SINK}:playback_FL\n"
+                  f"ardour:Master/audio_out 2\n  |-> {BT_SINK}:playback_FR\n")
+
+
+def test_master_on_a_bluetooth_headset_is_not_dangling(tmp_path):
+    """Monitoring on the Bose while the default sink is the laptop speaker: linking
+    Master to the speaker as well would leak the whole set into the room."""
+    calls, out = _reconcile(tmp_path, CTRL_LINKED + MASTER_ON_BOSE)
+    assert not [c for c in calls if c.startswith("ardour:Master")]
+    assert out == ""

tools/tidal-ardour-autoroute.sh

@@ -98,10 +98,13 @@ ctrl_source() {  # stdin: the `pw-link -lo` snapshot
     awk '/^Midi-Bridge:Midi Through:/ && !/playback/ { print; exit }'
 }
 
-# How many alsa_output sinks Ardour Master reaches.
+# How many sound devices Ardour Master reaches. A Bluetooth headset counts: if the
+# set is monitored on the Bose, a Master linked only to bluez_output.* HAS an
+# output, and "fixing" it by also linking the laptop speaker would leak the whole
+# set into the room.
 master_hw_links() {  # stdin: the `pw-link -lo` snapshot
     awk '/^[^ \t]/ { src = $0; next }
-         index(src, "ardour:Master/audio_out") == 1 && /alsa_output\./ { n++ }
+         index(src, "ardour:Master/audio_out") == 1 && /(alsa|bluez)_output\./ { n++ }
          END { print n + 0 }'
 }