Refactor MinimalWindowManager for better specialization

[Copilot]

Related: Issue describing difficulty in specializing MinimalWindowManager

What's new?

Added three new protected helper methods to MinimalWindowManager that allow subclasses to interact with the internal application_selector state. This enables subclasses to customize window management behavior (such as implementing "sloppy focus") while maintaining proper application selector state.

• New Protected Methods: Added application_selector_advise_focus_gained(), application_selector_advise_focus_lost(), and application_selector_advise_delete_window() as protected non-virtual methods
• Refactored Existing Methods: Updated advise_focus_gained(), advise_focus_lost(), and advise_delete_window() to call the new helper methods
• Version Bump: Incremented MIRAL_VERSION_MINOR from 6 to 7 (now at 5.7.0)
• Symbol Export: Added new public symbols to src/miral/symbols.map under MIRAL_5.7 section and to debian/libmiral7.symbols with version 5.7.0
• Documentation: Added Doxygen comments for each new method marked as "Since MirAL 5.7"
• Tests: Added comprehensive tests verifying subclasses can use the helper methods and demonstrating the sloppy focus use case, using modern C++ (std::make_unique)

Example Usage

Subclasses can now override advise_focus_gained() without calling tools.raise_tree() (for sloppy focus behavior) while still maintaining the application selector state:

class SloppyFocusWindowManager : public miral::MinimalWindowManager
{
public:
    using MinimalWindowManager::MinimalWindowManager;

    void advise_focus_gained(miral::WindowInfo const& window_info) override
    {
        // Don't raise the tree for sloppy focus
        application_selector_advise_focus_gained(window_info);
    }
};

How to test

1. Run the new tests: CustomMinimalWindowManagerTest.application_selector_helpers_are_accessible_to_subclasses and CustomMinimalWindowManagerTest.sloppy_focus_does_not_raise_tree
2. Verify the code compiles successfully with the updated MIRAL version
3. Create a subclass of MinimalWindowManager that overrides advise_focus_gained() and uses the new application_selector_advise_focus_gained() helper method
4. Confirm that the application selector state is properly maintained when using the helper methods
5. Verify that the new symbols are properly exported in both src/miral/symbols.map and debian/libmiral7.symbols

Checklist

• Tests added and pass
• Adequate documentation added
• (optional) Added Screenshots or videos

Original prompt

---

This section details on the original issue you should resolve

<issue_title>MinimalWindowManager is hard to specialise</issue_title>
<issue_description>### Summary

MinimalWindowManager overrides a number of methods to update or use the application_selector but it is not possible to customise the methods as subclasses do not have access to this object. In particular:

void miral::MinimalWindowManager::advise_focus_gained(WindowInfo const& window_info)
{
    tools.raise_tree(window_info.window());
    self->application_selector.advise_focus_gained(window_info);
}

Should a specialization of MinimalWindowManager want to drop the raise_tree to allow "sloppy focus" it has no way to update the application_selector.

One plausible solution is to "extract method" these updates:

void miral::MinimalWindowManager::advise_focus_gained(WindowInfo const& window_info)
{
    tools.raise_tree(window_info.window());
    application_selector_advise_focus_gained(window_info);
}

void miral::MinimalWindowManager::application_selector_advise_focus_gained(WindowInfo const& window_info)
{
    self->application_selector.advise_focus_gained(window_info);
}

Making application_selector_advise_focus_gained() et alias a protected method.

Details

No response

Prior Art

No response</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes MinimalWindowManager is hard to specialise #4665

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.

[AlanGriffiths]

These new symbols also need adding to symbols.map and libmiral.symbols

[AlanGriffiths]

These new symbols also need adding to symbols.map and libmiral.symbols

@copilot

[Copilot]

These new symbols also need adding to symbols.map and libmiral.symbols

@copilot

Added new symbols in commit ffe4226. The three new methods are now exported in both:

• src/miral/symbols.map (MIRAL_5.7 section)
• debian/libmiral7.symbols (versioned as 5.7.0)

[AlanGriffiths]

@copilot please add some tests for this change

[Copilot]

Pull request overview

This PR refactors MinimalWindowManager to enable better specialization by subclasses. The changes add three new protected helper methods that expose the internal application_selector state management, allowing subclasses to customize window management behaviors (like implementing "sloppy focus") while maintaining proper application selector state.

Changes:

• Added three new protected helper methods for application selector state management
• Refactored existing advise_* methods to delegate to the new helpers
• Bumped MIRAL version from 5.6.0 to 5.7.0
• Updated symbol export files with new public symbols

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 1 comment.

File	Description
include/miral/miral/minimal_window_manager.h	Declares three new protected helper methods with Doxygen documentation
src/miral/minimal_window_manager.cpp	Implements the new helper methods and refactors existing methods to use them
src/CMakeLists.txt	Increments MIRAL_VERSION_MINOR from 6 to 7
debian/libmiral7.symbols	Adds new symbols under MIRAL_5.7 version

[Copilot]

@copilot please add some tests for this change

Added tests in commit b93dd14. The tests verify:

1. Subclasses can access and use the protected helper methods to interact with application_selector
2. The sloppy focus use case from the issue - overriding advise_focus_gained without calling raise_tree while still maintaining application_selector state

[AlanGriffiths]

@copilot please don't use raw new - we have had make_unique since C++14

[Copilot]

Fixed in commit 973b218. Changed to use std::make_unique and capture the raw pointer with .get().

stale