Allow forcing tab-mute to a specific value

Based on the David Leavenworth's <dleavenworth3@gmail.com> work.
Tests were written with the help of Claude Sonnet 4.5.

Fix tests: use fake_web_tab fixture and parametrization

qutebrowser/components/misccommands.py

@@ -322,16 +322,23 @@ def debug_webaction(tab: apitypes.Tab, action: str, count: int = 1) -> None:
 
 @cmdutils.register()
 @cmdutils.argument('tab', value=cmdutils.Value.count_tab)
-def tab_mute(tab: Optional[apitypes.Tab]) -> None:
+@cmdutils.argument('mute', choices=['true', 'false'])
+def tab_mute(tab: Optional[apitypes.Tab], mute: str = None) -> None:
     """Mute/Unmute the current/[count]th tab.
 
     Args:
         count: The tab index to mute or unmute, or None
+        mute: The mute setting to force : 'true' to mute, 'false' to unmute, omit to toggle.
     """
     if tab is None:
         return
     try:
-        tab.audio.set_muted(not tab.audio.is_muted(), override=True)
+        if mute == 'true':
+            tab.audio.set_muted(True, override=True)
+        elif mute == 'false':
+            tab.audio.set_muted(False, override=True)
+        else:
+            tab.audio.set_muted(not tab.audio.is_muted(), override=True)
     except apitypes.WebTabError as e:
         raise cmdutils.CommandError(e)
 

tests/helpers/stubs.py

@@ -225,8 +225,16 @@ class FakeWebTabHistory(browsertab.AbstractHistory):
 
 class FakeWebTabAudio(browsertab.AbstractAudio):
 
+    def __init__(self, tab):
+        super().__init__(tab)
+        self._is_muted = False
+
     def is_muted(self):
-        return False
+        return self._is_muted
+
+    def set_muted(self, muted: bool, override: bool = False) -> None:
+        """Set muted state."""
+        self._is_muted = muted
 
     def is_recently_audible(self):
         return False

tests/unit/components/test_misccommands.py

@@ -77,3 +77,19 @@ def test_debug_trace_no_hunter(monkeypatch):
     with pytest.raises(cmdutils.CommandError, match="You need to install "
                        "'hunter' to use this command!"):
         misccommands.debug_trace()
+
+
+@pytest.mark.parametrize("initial_muted,mute_arg,expected_muted", [
+    (False, None, True),      # Toggle: Unmuted → muted
+    (True, None, False),      # Toggle: Muted → unmuted
+    (False, 'true', True),    # Force mute
+    (True, 'true', True),     # Force mute (idempotent)
+    (False, 'false', False),  # Force unmute (idempotent)
+    (True, 'false', False),   # Force unmute
+])
+def test_tab_mute(fake_web_tab, initial_muted, mute_arg, expected_muted):
+    """Test tab_mute with different states and parameters."""
+    tab = fake_web_tab()
+    tab.audio.set_muted(initial_muted)
+    misccommands.tab_mute(tab, mute=mute_arg)
+    assert tab.audio.is_muted() == expected_muted