Fix WindowTabs use of parse_text

[heitzmann]

This fixes the issue raised in #3741 by using the parser function for each window title before any state or markup is applied, similarly to what is done for the TaskList widget.

Additionally, instead of checking if the value is callable, it uses a default callable value and also skips the try...except block. I believe any raised errors will be logged anyway, won't they? And with better debug information than only "parse_text function failed:"

[elParaguayo]

Thanks for this. I've made a request for one change.

[elParaguayo]

Thanks for the updates. I've added one question.

Also, would be good to add a test for this. This should do it:

diff --git a/test/widgets/test_windowtabs.py b/test/widgets/test_windowtabs.py
index 424044b7..f582b8cd 100644
--- a/test/widgets/test_windowtabs.py
+++ b/test/widgets/test_windowtabs.py
@@ -28,6 +28,10 @@ from libqtile.config import Screen
 from libqtile.confreader import Config


+def custom_text_parser(name):
+    return f"TEST-{name}-TEST"
+
+
 class WindowTabsConfig(Config):
     auto_fullscreen = True
     groups = [libqtile.config.Group("a"), libqtile.config.Group("b")]
@@ -40,6 +44,7 @@ class WindowTabsConfig(Config):
             top=bar.Bar(
                 [
                     widget.WindowTabs(),
+                    widget.WindowTabs(name="customparse", parse_text=custom_text_parser)
                 ],
                 24,
             ),
@@ -136,3 +141,14 @@ def test_escaping_text(manager):
     """
     manager.test_window("Text & Text")
     assert manager.c.widget["windowtabs"].info()["text"] == "<b>Text &amp; Text</b>"
+
+
+@windowtabs_config
+def test_custom_text_parser(manager):
+    """Test the custom text parser function."""
+    manager.test_window("one")
+    assert manager.c.widget["customparse"].info()["text"] == "<b>TEST-one-TEST</b>"

[elParaguayo]

Do you need the if w part of the check here? If there any scenario where w is not a window object?

[heitzmann]

That I'm not sure. It comes from the original implementation, so I kept it.

[elParaguayo]

Great. This looks ok now. I'll set it to merge once tests pass.