Ignore tabs.last_close with tabs.tabs_are_windows

Closes #5695
Supersedes #5771

doc/changelog.asciidoc

@@ -110,6 +110,8 @@ Changed
 - The `importer.py` script doesn't use a browser argument anymore; instead its
   `--input-format` switch can be used to configure the input format. The help also
   was expanded to explain how to use it properly.
+- If `tabs.tabs_are_windows` is set, the `tabs.last_close` setting is now
+  ignored and the window is always closed when using `:close` (`d`).
 
 Fixed
 ~~~~~

doc/help/settings.asciidoc

@@ -3812,6 +3812,7 @@ Default: +pass:[3]+
 [[tabs.last_close]]
 === tabs.last_close
 How to behave when the last tab is closed.
+If the `tabs.tabs_are_windows` setting is set, this is ignored and the behavior is always identical to the `close` value.
 
 Type: <<types,String>>
 

qutebrowser/config/configdata.yml

@@ -1685,7 +1685,11 @@ tabs.last_close:
       - startpage: "Load the start page."
       - default-page: "Load the default page."
       - close: "Close the window."
-  desc: How to behave when the last tab is closed.
+  desc: >-
+    How to behave when the last tab is closed.
+
+    If the `tabs.tabs_are_windows` setting is set, this is ignored and the behavior is
+    always identical to the `close` value.
 
 tabs.mousewheel_switching:
   default: true

qutebrowser/mainwindow/tabbedbrowser.py

@@ -411,7 +411,11 @@ class TabbedBrowser(QWidget):
             add_undo: Whether the tab close can be undone.
             new_undo: Whether the undo entry should be a new item in the stack.
         """
-        last_close = config.val.tabs.last_close
+        if config.val.tabs.tabs_are_windows:
+            last_close = 'close'
+        else:
+            last_close = config.val.tabs.last_close
+
         count = self.widget.count()
 
         if last_close == 'ignore' and count == 1:

tests/end2end/features/tabs.feature

@@ -6,6 +6,7 @@ Feature: Tab management
     Background:
         Given I clean up open tabs
         And I set tabs.tabs_are_windows to false
+        And I clear the log
 
     # :tab-close
 
@@ -1415,6 +1416,21 @@ Feature: Tab management
               - history:
                 - url: http://localhost:*/data/hello.txt
 
+    Scenario: Closing tab with tabs_are_windows
+        When I set tabs.tabs_are_windows to true
+        And I set tabs.last_close to ignore
+        And I open data/numbers/1.txt
+        And I open data/numbers/2.txt in a new tab
+        And I run :tab-close
+        And I wait for "removed: tabbed-browser" in the log
+        Then the session should look like:
+            windows:
+            - tabs:
+              - active: true
+                history:
+                - url: about:blank
+                - url: http://localhost:*/data/numbers/1.txt
+
     # :tab-pin
 
     Scenario: :tab-pin command