refactor(package-discovery): extend BaseCommand as supertrait

PHP's PackageDiscoveryTrait is mixed into classes extending BaseCommand
and calls its methods directly. Model that with a supertrait bound so
get_io, try_composer, require_composer, get_platform_requirement_filter
and normalize_requirements come from BaseCommand instead of being
redeclared and delegated per command. Propagate the Result returns at
the call sites and drop the now-redundant per-command impls.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

3 files changed, 7 insertions, 81 deletions

diff --git a/crates/shirabe/src/command/init_command.rs b/crates/shirabe/src/command/init_command.rs
index f345d76..d7beaf8 100644
--- a/crates/shirabe/src/command/init_command.rs
+++ b/crates/shirabe/src/command/init_command.rs
@@ -65,35 +65,6 @@ impl PackageDiscoveryTrait for InitCommand {
     {
         &mut self.repository_sets
     }
-
-    fn get_io(&self) -> std::rc::Rc<std::cell::RefCell<dyn IOInterface>> {
-        todo!()
-    }
-
-    fn try_composer(&self) -> Option<PartialComposerHandle> {
-        todo!()
-    }
-
-    fn require_composer(
-        &self,
-        disable_plugins: Option<bool>,
-        disable_scripts: Option<bool>,
-    ) -> PartialComposerHandle {
-        todo!()
-    }
-
-    fn get_platform_requirement_filter(
-        &self,
-        input: std::rc::Rc<std::cell::RefCell<dyn InputInterface>>,
-    ) -> std::rc::Rc<
-        dyn crate::filter::platform_requirement_filter::PlatformRequirementFilterInterface,
-    > {
-        todo!()
-    }
-
-    fn normalize_requirements(&self, requires: Vec<String>) -> Vec<IndexMap<String, String>> {
-        todo!()
-    }
 }
 
 impl Default for InitCommand {
@@ -152,7 +123,7 @@ impl Command for InitCommand {
         input: Rc<RefCell<dyn InputInterface>>,
         output: Rc<RefCell<dyn OutputInterface>>,
     ) -> anyhow::Result<i64> {
-        let io = PackageDiscoveryTrait::get_io(self);
+        let io = self.get_io();
 
         let allowlist: Vec<String> = vec![
             "name".to_string(),
diff --git a/crates/shirabe/src/command/package_discovery_trait.rs b/crates/shirabe/src/command/package_discovery_trait.rs
index e2ffa7c..c182645 100644
--- a/crates/shirabe/src/command/package_discovery_trait.rs
+++ b/crates/shirabe/src/command/package_discovery_trait.rs
@@ -15,6 +15,7 @@ use shirabe_php_shim::{
     strpos, trim,
 };
 
+use crate::command::BaseCommand;
 use crate::composer::PartialComposerHandle;
 use crate::factory::Factory;
 use crate::filter::platform_requirement_filter::IgnoreAllPlatformRequirementFilter;
@@ -33,7 +34,7 @@ use crate::repository::{RepositoryInterface, SearchResult};
 use crate::util::Filesystem;
 
 /// @internal
-pub trait PackageDiscoveryTrait {
+pub trait PackageDiscoveryTrait: BaseCommand {
     // PHP: private $repos; private $repositorySets;
     // TODO(phase-b): trait fields require an associated state struct in Rust; expose via accessors
     fn get_repos_mut(&mut self) -> &mut Option<crate::repository::RepositoryInterfaceHandle>;
@@ -41,23 +42,6 @@ pub trait PackageDiscoveryTrait {
         &mut self,
     ) -> &mut IndexMap<String, std::rc::Rc<std::cell::RefCell<RepositorySet>>>;
 
-    // PHP: trait dependencies (provided by BaseCommand)
-    fn get_io(&self) -> std::rc::Rc<std::cell::RefCell<dyn IOInterface>>;
-    fn try_composer(&self) -> Option<PartialComposerHandle>;
-    fn require_composer(
-        &self,
-        disable_plugins: Option<bool>,
-        disable_scripts: Option<bool>,
-    ) -> PartialComposerHandle;
-    fn get_platform_requirement_filter(
-        &self,
-        input: std::rc::Rc<std::cell::RefCell<dyn InputInterface>>,
-    ) -> std::rc::Rc<
-        dyn crate::filter::platform_requirement_filter::PlatformRequirementFilterInterface,
-    >;
-
-    fn normalize_requirements(&self, requires: Vec<String>) -> Vec<IndexMap<String, String>>;
-
     fn get_repos(&mut self) -> crate::repository::RepositoryInterfaceHandle {
         if self.get_repos_mut().is_none() {
             // PHP: array_merge([new PlatformRepository], RepositoryFactory::defaultReposWithDefaultManager($this->getIO()))
@@ -160,7 +144,7 @@ pub trait PackageDiscoveryTrait {
         fixed: bool,
     ) -> Result<Vec<String>> {
         if !requires.is_empty() {
-            let requires_norm = self.normalize_requirements(requires.clone());
+            let requires_norm = self.normalize_requirements(requires.clone())?;
             let mut result: Vec<String> = vec![];
             let io = self.get_io();
 
@@ -228,7 +212,7 @@ pub trait PackageDiscoveryTrait {
         let version_parser = VersionParser::new();
 
         // Collect existing packages
-        let composer = self.try_composer();
+        let composer = self.try_composer(None, None);
         let composer_ref = composer.as_ref().map(|c| c.borrow_partial());
         let repository_manager = composer_ref
             .as_ref()
@@ -491,7 +475,7 @@ pub trait PackageDiscoveryTrait {
         let platform_requirement_filter = if input.borrow().has_option("ignore-platform-reqs")
             && input.borrow().has_option("ignore-platform-req")
         {
-            self.get_platform_requirement_filter(input.clone())
+            self.get_platform_requirement_filter(input.clone())?
         } else {
             PlatformRequirementFilterFactory::ignore_nothing()
         };
@@ -803,7 +787,7 @@ pub trait PackageDiscoveryTrait {
         };
         let mut similar_packages: IndexMap<String, i64> = IndexMap::new();
 
-        let composer_for_installed = self.require_composer(None, None);
+        let composer_for_installed = self.require_composer(None, None)?;
         let composer_for_installed = composer_for_installed.borrow_partial();
         let repository_manager = composer_for_installed.get_repository_manager().clone();
         let repository_manager = repository_manager.borrow();
diff --git a/crates/shirabe/src/command/require_command.rs b/crates/shirabe/src/command/require_command.rs
index 3d8331b..a29f60d 100644
--- a/crates/shirabe/src/command/require_command.rs
+++ b/crates/shirabe/src/command/require_command.rs
@@ -107,35 +107,6 @@ impl PackageDiscoveryTrait for RequireCommand {
     ) -> &mut IndexMap<String, std::rc::Rc<std::cell::RefCell<RepositorySet>>> {
         &mut self.repository_sets
     }
-
-    fn get_io(&self) -> std::rc::Rc<std::cell::RefCell<dyn IOInterface>> {
-        todo!()
-    }
-
-    fn try_composer(&self) -> Option<PartialComposerHandle> {
-        todo!()
-    }
-
-    fn require_composer(
-        &self,
-        disable_plugins: Option<bool>,
-        disable_scripts: Option<bool>,
-    ) -> PartialComposerHandle {
-        todo!()
-    }
-
-    fn get_platform_requirement_filter(
-        &self,
-        input: std::rc::Rc<std::cell::RefCell<dyn InputInterface>>,
-    ) -> std::rc::Rc<
-        dyn crate::filter::platform_requirement_filter::PlatformRequirementFilterInterface,
-    > {
-        todo!()
-    }
-
-    fn normalize_requirements(&self, requires: Vec<String>) -> Vec<IndexMap<String, String>> {
-        todo!()
-    }
 }
 
 impl Command for RequireCommand {