Extended the flatpak functionality to modules. All works as expected.

src/decman/__init__.py

@@ -380,6 +380,13 @@ class Module:
         """
         return []
 
+    def flatpak_packages(self) -> list[str]:
+        """
+        Override this method to return flatpak packages that should be installed as a part of this
+        Module.
+        """
+        return []
+
     def systemd_units(self) -> list[str]:
         """
         Override this method to return systemd units that should be enabled as a part of this

src/decman/lib/__init__.py

@@ -651,7 +651,7 @@ class Source:
         """
 
         result: list[str] = []
-        for pkg in self.flatpak_packages:
+        for pkg in self._all_flatpak_packages():
             if pkg in self.ignored_flatpak_packages:
                 continue
             if pkg not in currently_installed_packages:
@@ -668,7 +668,7 @@ class Source:
         for package in currently_installed_packages:
             if package in self.ignored_flatpak_packages:
                 continue
-            if package not in self.flatpak_packages:
+            if package not in self._all_flatpak_packages():
                 result.append(package)
 
         return result
@@ -702,6 +702,15 @@ class Source:
                 result.update(module.pacman_packages())
         return result
 
+    def _all_flatpak_packages(self) -> set[str]:
+        result = set()
+        result.update(self.flatpak_packages)
+        for module in self.modules:
+            if module.enabled:
+                result.update(module.flatpak_packages())
+
+        return result
+
     def _all_foreign_pkgs(self) -> set[str]:
         result = set()
         result.update(self.aur_packages)

tests/test_source_resolution.py

@@ -1,5 +1,6 @@
 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
 
+from typing import override
 import unittest
 from decman.lib import Source, Store
 from decman import UserPackage, Module
@@ -73,6 +74,9 @@ class EnabledTestModule(Module):
     def systemd_user_units(self) -> dict[str, list[str]]:
         return {"muser": ["M_u1.service"]}
 
+    def flatpak_packages(self) -> list[str]:
+        return ["M_f1", "M_f2"]
+
 
 class DisabledTestModule(Module):
     def __init__(self):