1 files changed, 81 insertions, 4 deletions

diff --git a/crates/shirabe/src/console/input.rs b/crates/shirabe/src/console/input.rs
index 9141f0cb..9661c7ad 100644
--- a/crates/shirabe/src/console/input.rs
+++ b/crates/shirabe/src/console/input.rs
@@ -4,9 +4,86 @@ pub mod input_option;
 pub use input_argument::*;
 pub use input_option::*;
 
+use shirabe_external_packages::symfony::console::completion::completion_input::CompletionInput;
+use shirabe_external_packages::symfony::console::completion::completion_suggestions::{
+    CompletionSuggestions, StringOrSuggestion,
+};
+
+/// PHP: `\Closure(CompletionInput,CompletionSuggestions):list<string|Suggestion>`.
+///
+/// PHP closures are bound to the command instance (`$this`); commands cannot capture a handle
+/// to themselves while `configure()` runs inside `new()`, so the bound command is passed in as
+/// `this` at call time instead.
+pub type SuggestedValuesClosure = Box<
+    dyn Fn(
+        &dyn crate::command::BaseCommand,
+        &CompletionInput,
+        &mut CompletionSuggestions,
+    ) -> anyhow::Result<Vec<String>>,
+>;
+
+/// PHP: the `list<string>|\Closure(...)` union taken by the suggestedValues parameter of the
+/// `Composer\Console\Input\InputArgument` / `InputOption` backport.
+///
+/// The closure returns `Vec<String>` rather than `list<string|Suggestion>`: every Composer
+/// closure returns plain strings, and `complete` lifts them into suggestions. PHP's runtime
+/// "Closure must return an array" LogicException is statically guaranteed by the type.
+pub enum SuggestedValues {
+    List(Vec<String>),
+    Closure(SuggestedValuesClosure),
+}
+
+impl std::fmt::Debug for SuggestedValues {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            SuggestedValues::List(values) => f.debug_tuple("List").field(values).finish(),
+            SuggestedValues::Closure(_) => f.write_str("Closure(..)"),
+        }
+    }
+}
+
+impl SuggestedValues {
+    /// Whether PHP's `[] !== $suggestedValues` is false, i.e. no suggestions were declared.
+    pub(crate) fn is_empty(&self) -> bool {
+        matches!(self, SuggestedValues::List(values) if values.is_empty())
+    }
+
+    /// The shared body of the `InputArgument::complete` / `InputOption::complete` backport.
+    pub(crate) fn complete(
+        &self,
+        this: &dyn crate::command::BaseCommand,
+        input: &CompletionInput,
+        suggestions: &mut CompletionSuggestions,
+    ) -> anyhow::Result<()> {
+        let values = match self {
+            SuggestedValues::List(values) => values.clone(),
+            SuggestedValues::Closure(closure) => closure(this, input, suggestions)?,
+        };
+        if !values.is_empty() {
+            suggestions
+                .suggest_values(values.into_iter().map(StringOrSuggestion::String).collect());
+        }
+        Ok(())
+    }
+
+    /// PHP: `$this->suggestX()($input)` — invoking a suggestion closure directly. Calling this
+    /// on a List is a programming error (PHP would fatal on `$array()`).
+    pub fn call(
+        &self,
+        this: &dyn crate::command::BaseCommand,
+        input: &CompletionInput,
+        suggestions: &mut CompletionSuggestions,
+    ) -> anyhow::Result<Vec<String>> {
+        match self {
+            SuggestedValues::Closure(closure) => closure(this, input, suggestions),
+            SuggestedValues::List(_) => panic!("SuggestedValues::call on a non-closure"),
+        }
+    }
+}
+
 pub enum InputDefinitionItem {
-    Argument(input_argument::InputArgument),
-    Option(input_option::InputOption),
+    Argument(std::rc::Rc<input_argument::InputArgument>),
+    Option(std::rc::Rc<input_option::InputOption>),
 }
 
 impl InputDefinitionItem {
@@ -26,12 +103,12 @@ impl InputDefinitionItem {
 
 impl From<input_argument::InputArgument> for InputDefinitionItem {
     fn from(value: input_argument::InputArgument) -> Self {
-        Self::Argument(value)
+        Self::Argument(std::rc::Rc::new(value))
     }
 }
 
 impl From<input_option::InputOption> for InputDefinitionItem {
     fn from(value: input_option::InputOption) -> Self {
-        Self::Option(value)
+        Self::Option(std::rc::Rc::new(value))
     }
 }