feat(displays): monitors w/ resolution+refresh in Inventory; flag sub-max refresh in Health — 0.39.0

New core/displays.py reads connected monitors via GNOME Mutter DisplayConfig over
D-Bus (busctl --json; works on X11 + Wayland), falling back to xrandr on other X11
desktops. Inventory's Display section now lists each monitor's resolution + current
refresh (e.g. 'DP-1 · Samsung LC34G55T: 3440x1440 @ 165 Hz'). System Health
(check_displays) flags a monitor running below its max refresh AT THE CURRENT
resolution (e.g. 165 Hz panel set to 60 Hz) — never suggests lowering resolution.
+tests (Mutter JSON + xrandr parsers, health check).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/test_displays.py

@@ -0,0 +1,67 @@
+"""Tests for display detection (Mutter D-Bus JSON + xrandr parsers)."""
+
+import unittest
+
+from rigdoctor.core import displays
+
+# Minimal Mutter GetCurrentState (busctl --json) shape: current mode is 60 Hz, panel max 165 Hz.
+_MUTTER_60 = (
+    '{"type":"x","data":[1,[[["DP-1","SAM","LC34G55T","S"],['
+    '["3440x1440@60",3440,1440,60.0,1.0,[1.0],{"is-current":{"type":"b","data":true}}],'
+    '["3440x1440@165",3440,1440,165.0,1.0,[1.0],{"is-preferred":{"type":"b","data":true}}]'
+    '],{}]],[],{}]}'
+)
+_MUTTER_MAX = (
+    '{"type":"x","data":[1,[[["DP-1","SAM","LC34G55T","S"],['
+    '["3440x1440@165",3440,1440,165.0,1.0,[1.0],{"is-current":{"type":"b","data":true}}],'
+    '["3440x1440@60",3440,1440,60.0,1.0,[1.0],{}]'
+    '],{}]],[],{}]}'
+)
+
+_XRANDR_60 = """Screen 0: minimum 8 x 8, current 3440 x 1440, maximum 16384 x 16384
+DP-1 connected primary 3440x1440+0+0 (normal left inverted right x axis y axis) 800mm x 335mm
+   3440x1440     60.00*+  165.00   100.00
+   2560x1440    165.00    60.00
+HDMI-1 disconnected (normal left inverted right x axis y axis)
+"""
+
+
+class MutterParseTests(unittest.TestCase):
+    def test_parses_and_flags_higher_refresh(self):
+        mons = displays._parse_mutter(_MUTTER_60)
+        self.assertEqual(len(mons), 1)
+        m = mons[0]
+        self.assertEqual(m.connector, "DP-1")
+        self.assertEqual(m.name, "Samsung LC34G55T")  # PNP code SAM mapped
+        self.assertEqual((m.width, m.height), (3440, 1440))
+        self.assertEqual(round(m.refresh), 60)
+        self.assertEqual(round(m.max_refresh), 165)
+        self.assertTrue(m.can_go_faster)
+
+    def test_at_max_is_not_flagged(self):
+        m = displays._parse_mutter(_MUTTER_MAX)[0]
+        self.assertEqual(round(m.refresh), 165)
+        self.assertFalse(m.can_go_faster)
+
+    def test_garbage_returns_empty(self):
+        self.assertEqual(displays._parse_mutter("not json"), [])
+        self.assertEqual(displays._parse_mutter("{}"), [])
+
+
+class XrandrParseTests(unittest.TestCase):
+    def test_current_and_max_refresh(self):
+        mons = displays._parse_xrandr(_XRANDR_60)
+        self.assertEqual(len(mons), 1)  # disconnected output ignored
+        m = mons[0]
+        self.assertEqual(m.connector, "DP-1")
+        self.assertEqual((m.width, m.height), (3440, 1440))
+        self.assertEqual(round(m.refresh), 60)
+        self.assertEqual(round(m.max_refresh), 165)
+        self.assertTrue(m.can_go_faster)
+
+    def test_empty_returns_empty(self):
+        self.assertEqual(displays._parse_xrandr(""), [])
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_health.py

@@ -4,11 +4,12 @@ import unittest
 from pathlib import Path
 from unittest import mock
 
-from rigdoctor.core import health
+from rigdoctor.core import displays, health
 from rigdoctor.core.health import (
     CRITICAL,
     INFO,
     WARNING,
+    check_displays,
     check_pcie_links,
     run_health_checks,
     scan_journal_text,
@@ -81,5 +82,20 @@ class PcieLinkCheckTests(unittest.TestCase):
             self.assertEqual(check_pcie_links(), [])
 
 
+class DisplayCheckTests(unittest.TestCase):
+    def test_lower_than_max_refresh_is_flagged(self):
+        mon = displays.Monitor("DP-1", "Samsung LC34G55T", 3440, 1440, 60.0, 165.0)
+        with mock.patch("rigdoctor.core.displays.collect", return_value=[mon]):
+            findings = check_displays()
+        self.assertEqual(len(findings), 1)
+        self.assertEqual(findings[0].severity, INFO)
+        self.assertIn("165", findings[0].title)
+
+    def test_at_max_refresh_no_finding(self):
+        mon = displays.Monitor("DP-1", "Samsung LC34G55T", 3440, 1440, 165.0, 165.0)
+        with mock.patch("rigdoctor.core.displays.collect", return_value=[mon]):
+            self.assertEqual(check_displays(), [])
+
+
 if __name__ == "__main__":
     unittest.main()