feat(composite-repository): forward remove_package to writable repos

Resolve the phase-b TODO by adding an as_writable_repository_interface_mut
downcast helper on RepositoryInterface, mirroring PHP's instanceof
WritableRepositoryInterface check, and propagate inner errors.

4 files changed, 25 insertions, 5 deletions

diff --git a/crates/shirabe/src/repository/composite_repository.rs b/crates/shirabe/src/repository/composite_repository.rs
index 78bbc6a..97fad44 100644
--- a/crates/shirabe/src/repository/composite_repository.rs
+++ b/crates/shirabe/src/repository/composite_repository.rs
@@ -32,12 +32,16 @@ impl CompositeRepository {
         &self.repositories
     }
 
-    pub fn remove_package(&mut self, _package: PackageInterfaceHandle) {
-        // TODO(phase-b): only call remove_package on WritableRepositoryInterface implementors;
-        // requires a downcast helper such as `as_writable() -> Option<&mut dyn WritableRepositoryInterface>` on RepositoryInterface.
-        for _repository in &mut self.repositories {
-            todo!()
+    pub fn remove_package(&mut self, package: PackageInterfaceHandle) -> anyhow::Result<()> {
+        for repository in &self.repositories {
+            if let Some(writable) = repository
+                .borrow_mut()
+                .as_writable_repository_interface_mut()
+            {
+                writable.remove_package(package.clone())?;
+            }
         }
+        Ok(())
     }
 
     pub fn add_repository(&mut self, repository: RepositoryInterfaceHandle) {
diff --git a/crates/shirabe/src/repository/installed_array_repository.rs b/crates/shirabe/src/repository/installed_array_repository.rs
index 2d3965b..64098e9 100644
--- a/crates/shirabe/src/repository/installed_array_repository.rs
+++ b/crates/shirabe/src/repository/installed_array_repository.rs
@@ -151,6 +151,11 @@ impl RepositoryInterface for InstalledArrayRepository {
     ) -> Option<&mut dyn InstalledRepositoryInterface> {
         Some(self)
     }
+    fn as_writable_repository_interface_mut(
+        &mut self,
+    ) -> Option<&mut dyn crate::repository::WritableRepositoryInterface> {
+        Some(self)
+    }
     fn as_any(&self) -> &dyn std::any::Any {
         todo!()
     }
diff --git a/crates/shirabe/src/repository/installed_filesystem_repository.rs b/crates/shirabe/src/repository/installed_filesystem_repository.rs
index 84bf1ca..1f6be2c 100644
--- a/crates/shirabe/src/repository/installed_filesystem_repository.rs
+++ b/crates/shirabe/src/repository/installed_filesystem_repository.rs
@@ -161,6 +161,11 @@ impl RepositoryInterface for InstalledFilesystemRepository {
     ) -> Option<&mut dyn InstalledRepositoryInterface> {
         Some(self)
     }
+    fn as_writable_repository_interface_mut(
+        &mut self,
+    ) -> Option<&mut dyn crate::repository::WritableRepositoryInterface> {
+        Some(self)
+    }
     fn as_any(&self) -> &dyn std::any::Any {
         todo!()
     }
diff --git a/crates/shirabe/src/repository/repository_interface.rs b/crates/shirabe/src/repository/repository_interface.rs
index 249bd85..e3a5548 100644
--- a/crates/shirabe/src/repository/repository_interface.rs
+++ b/crates/shirabe/src/repository/repository_interface.rs
@@ -111,6 +111,12 @@ pub trait RepositoryInterface: Countable + std::fmt::Debug {
         None
     }
 
+    fn as_writable_repository_interface_mut(
+        &mut self,
+    ) -> Option<&mut dyn crate::repository::WritableRepositoryInterface> {
+        None
+    }
+
     fn as_any(&self) -> &dyn std::any::Any;
 
     /// Injects this repository's own weak handle so that `add_package` can wire package ->