feat(question): model Question hierarchy via QuestionInterface trait

Introduce a QuestionInterface trait that the base Question and all its
subclasses (ChoiceQuestion, ConfirmationQuestion, StrictConfirmationQuestion)
implement, with as_choice/as_confirmation downcasts standing in for PHP's
instanceof. Consumers (QuestionHelper, SymfonyQuestionHelper, SymfonyStyle,
ConsoleIO) now take a QuestionInterface boundary generically.

This fixes the instanceof emulation, which previously went through
as_any().downcast_ref on a concrete &Question and always returned None, and
unblocks the select/confirm/choice paths that were left as todo!() because a
polymorphic ChoiceQuestion/ConfirmationQuestion could not be passed to ask.

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

7 files changed, 251 insertions, 57 deletions

diff --git a/crates/shirabe-external-packages/src/symfony/console/helper/question_helper.rs b/crates/shirabe-external-packages/src/symfony/console/helper/question_helper.rs
index 9eb8fff..1fc90bd 100644
--- a/crates/shirabe-external-packages/src/symfony/console/helper/question_helper.rs
+++ b/crates/shirabe-external-packages/src/symfony/console/helper/question_helper.rs
@@ -15,8 +15,8 @@ use crate::symfony::console::output::console_output_interface::ConsoleOutputInte
 use crate::symfony::console::output::console_section_output::ConsoleSectionOutput;
 use crate::symfony::console::output::output_interface;
 use crate::symfony::console::output::output_interface::OutputInterface;
-use crate::symfony::console::question::choice_question::ChoiceQuestion;
-use crate::symfony::console::question::question::Question;
+use crate::symfony::console::question::ChoiceQuestion;
+use crate::symfony::console::question::QuestionInterface;
 use crate::symfony::console::terminal::Terminal;
 use crate::symfony::string::s;
 use shirabe_php_shim::AsAny;
@@ -48,7 +48,7 @@ impl QuestionHelper {
         &mut self,
         input: &mut dyn InputInterface,
         output: Rc<RefCell<dyn OutputInterface>>,
-        question: &Question,
+        question: &impl QuestionInterface,
     ) -> anyhow::Result<Result<PhpMixed, MissingInputException>> {
         let mut output = output;
         let error_output = {
@@ -115,7 +115,7 @@ impl QuestionHelper {
     fn do_ask(
         &self,
         output: Rc<RefCell<dyn OutputInterface>>,
-        question: &Question,
+        question: &impl QuestionInterface,
     ) -> anyhow::Result<Result<PhpMixed, MissingInputException>> {
         self.write_prompt(Rc::clone(&output), question);
 
@@ -220,7 +220,7 @@ impl QuestionHelper {
     }
 
     /// @return mixed
-    fn get_default_answer(&self, question: &Question) -> PhpMixed {
+    fn get_default_answer(&self, question: &impl QuestionInterface) -> PhpMixed {
         let default = question.get_default();
 
         if matches!(default, PhpMixed::Null) {
@@ -230,7 +230,7 @@ impl QuestionHelper {
         if let Some(validator) = question.get_validator() {
             // call_user_func($question->getValidator(), $default)
             return validator(Some(default)).unwrap();
-        } else if let Some(choice_question) = question_as_choice_question(question) {
+        } else if let Some(choice_question) = question.as_choice() {
             let choices = choice_question.get_choices();
 
             if !choice_question.is_multiselect() {
@@ -262,11 +262,11 @@ impl QuestionHelper {
     pub(crate) fn write_prompt(
         &self,
         output: Rc<RefCell<dyn OutputInterface>>,
-        question: &Question,
+        question: &impl QuestionInterface,
     ) {
         let mut message = question.get_question().to_string();
 
-        if let Some(choice_question) = question_as_choice_question(question) {
+        if let Some(choice_question) = question.as_choice() {
             let mut lines = vec![question.get_question().to_string()];
             lines.extend(self.format_choice_question_choices(choice_question, "info"));
             output
@@ -339,7 +339,7 @@ impl QuestionHelper {
     fn autocomplete(
         &self,
         output: Rc<RefCell<dyn OutputInterface>>,
-        question: &Question,
+        question: &impl QuestionInterface,
         input_stream: &shirabe_php_shim::PhpResource,
         autocomplete: &dyn Fn(&str) -> Vec<PhpMixed>,
     ) -> String {
@@ -518,7 +518,7 @@ impl QuestionHelper {
 
                 let mut temp_ret = ret.clone();
 
-                if let Some(choice_question) = question_as_choice_question(question)
+                if let Some(choice_question) = question.as_choice()
                     && choice_question.is_multiselect()
                 {
                     temp_ret = self.most_recently_entered_value(&full_choice);
@@ -680,7 +680,7 @@ impl QuestionHelper {
         &self,
         interviewer: &dyn Fn() -> anyhow::Result<Result<PhpMixed, MissingInputException>>,
         output: Rc<RefCell<dyn OutputInterface>>,
-        question: &Question,
+        question: &impl QuestionInterface,
     ) -> anyhow::Result<Result<PhpMixed, MissingInputException>> {
         let mut error: Option<shirabe_php_shim::Exception> = None;
         let mut attempts = question.get_max_attempts();
@@ -752,7 +752,7 @@ impl QuestionHelper {
     fn read_input(
         &self,
         input_stream: &shirabe_php_shim::PhpResource,
-        question: &Question,
+        question: &impl QuestionInterface,
     ) -> PhpMixed {
         if !question.is_multiline() {
             let cp = self.set_io_codepage();
@@ -869,11 +869,6 @@ impl QuestionHelper {
     }
 }
 
-/// Downcasts a Question to a ChoiceQuestion if applicable.
-fn question_as_choice_question(question: &Question) -> Option<&ChoiceQuestion> {
-    question.as_any().downcast_ref::<ChoiceQuestion>()
-}
-
 // PHP `__FILE__` magic constant. The shim's `file()` is PHP's file() function,
 // not the magic constant, and there is no `__FILE__` shim yet (see report).
 fn magic_file() -> String {
diff --git a/crates/shirabe-external-packages/src/symfony/console/helper/symfony_question_helper.rs b/crates/shirabe-external-packages/src/symfony/console/helper/symfony_question_helper.rs
index c1d8455..9940896 100644
--- a/crates/shirabe-external-packages/src/symfony/console/helper/symfony_question_helper.rs
+++ b/crates/shirabe-external-packages/src/symfony/console/helper/symfony_question_helper.rs
@@ -4,9 +4,7 @@ use crate::symfony::console::formatter::output_formatter::OutputFormatter;
 use crate::symfony::console::helper::question_helper::QuestionHelper;
 use crate::symfony::console::output::output_interface;
 use crate::symfony::console::output::output_interface::OutputInterface;
-use crate::symfony::console::question::choice_question::ChoiceQuestion;
-use crate::symfony::console::question::confirmation_question::ConfirmationQuestion;
-use crate::symfony::console::question::question::Question;
+use crate::symfony::console::question::QuestionInterface;
 use crate::symfony::console::style::symfony_style::SymfonyStyle;
 use shirabe_php_shim::AsAny;
 use shirabe_php_shim::PhpMixed;
@@ -28,7 +26,7 @@ impl SymfonyQuestionHelper {
     pub(crate) fn write_prompt(
         &self,
         output: Rc<RefCell<dyn OutputInterface>>,
-        question: &Question,
+        question: &impl QuestionInterface,
     ) {
         let mut text = OutputFormatter::escape_trailing_backslash(question.get_question());
         let default = question.get_default();
@@ -43,11 +41,7 @@ impl SymfonyQuestionHelper {
         // switch (true)
         if matches!(default, PhpMixed::Null) {
             text = format!(" <info>{}</info>:", PhpMixed::String(text));
-        } else if question
-            .as_any()
-            .downcast_ref::<ConfirmationQuestion>()
-            .is_some()
-        {
+        } else if question.as_confirmation().is_some() {
             text = format!(
                 " <info>{} (yes/no)</info> [<comment>{}</comment>]:",
                 PhpMixed::String(text),
@@ -60,11 +54,7 @@ impl SymfonyQuestionHelper {
                     .to_string(),
                 ),
             );
-        } else if let Some(choice_question) = question
-            .as_any()
-            .downcast_ref::<ChoiceQuestion>()
-            .filter(|q| q.is_multiselect())
-        {
+        } else if let Some(choice_question) = question.as_choice().filter(|q| q.is_multiselect()) {
             let choices = choice_question.get_choices();
             let default_parts = shirabe_php_shim::explode(",", &default.to_string());
 
@@ -83,7 +73,7 @@ impl SymfonyQuestionHelper {
                 PhpMixed::String(text),
                 PhpMixed::String(OutputFormatter::escape(&resolved.join(", ")).unwrap()),
             );
-        } else if let Some(choice_question) = question.as_any().downcast_ref::<ChoiceQuestion>() {
+        } else if let Some(choice_question) = question.as_choice() {
             let choices = choice_question.get_choices();
             text = format!(
                 " <info>{}</info> [<comment>{}</comment>]:",
@@ -113,7 +103,7 @@ impl SymfonyQuestionHelper {
 
         let mut prompt = " > ".to_string();
 
-        if let Some(choice_question) = question.as_any().downcast_ref::<ChoiceQuestion>() {
+        if let Some(choice_question) = question.as_choice() {
             output.borrow().writeln(
                 &self
                     .inner
diff --git a/crates/shirabe-external-packages/src/symfony/console/question/choice_question.rs b/crates/shirabe-external-packages/src/symfony/console/question/choice_question.rs
index 24d434d..b862eb8 100644
--- a/crates/shirabe-external-packages/src/symfony/console/question/choice_question.rs
+++ b/crates/shirabe-external-packages/src/symfony/console/question/choice_question.rs
@@ -3,6 +3,7 @@
 use crate::symfony::console::exception::invalid_argument_exception::InvalidArgumentException;
 use crate::symfony::console::exception::logic_exception::LogicException;
 use crate::symfony::console::question::Question;
+use crate::symfony::console::question::QuestionInterface;
 use indexmap::IndexMap;
 use shirabe_php_shim::PhpMixed;
 
@@ -83,6 +84,16 @@ impl ChoiceQuestion {
         self
     }
 
+    /// Inherited from Question. Sets the maximum number of attempts.
+    pub fn set_max_attempts(
+        &mut self,
+        attempts: Option<i64>,
+    ) -> Result<&mut Self, InvalidArgumentException> {
+        self.inner.set_max_attempts(attempts)?;
+
+        Ok(self)
+    }
+
     /// Sets the error message for invalid values.
     ///
     /// The error message has a string placeholder (%s) for the invalid value.
@@ -229,6 +240,58 @@ impl ChoiceQuestion {
     }
 }
 
+impl QuestionInterface for ChoiceQuestion {
+    fn get_question(&self) -> &str {
+        self.inner.get_question()
+    }
+
+    fn get_default(&self) -> PhpMixed {
+        self.inner.get_default()
+    }
+
+    fn is_multiline(&self) -> bool {
+        self.inner.is_multiline()
+    }
+
+    fn is_hidden(&self) -> bool {
+        self.inner.is_hidden()
+    }
+
+    fn is_hidden_fallback(&self) -> bool {
+        self.inner.is_hidden_fallback()
+    }
+
+    fn get_autocompleter_values(&self) -> Option<Vec<PhpMixed>> {
+        self.inner.get_autocompleter_values()
+    }
+
+    fn get_autocompleter_callback(&self) -> Option<&(dyn Fn(&str) -> Option<Vec<PhpMixed>>)> {
+        self.inner.get_autocompleter_callback()
+    }
+
+    fn get_validator(
+        &self,
+    ) -> Option<&(dyn Fn(Option<PhpMixed>) -> Result<PhpMixed, InvalidArgumentException>)> {
+        self.inner.get_validator()
+    }
+
+    fn get_max_attempts(&self) -> Option<i64> {
+        self.inner.get_max_attempts()
+    }
+
+    fn get_normalizer(&self) -> Option<&(dyn Fn(PhpMixed) -> PhpMixed)> {
+        self.inner.get_normalizer()
+    }
+
+    fn is_trimmable(&self) -> bool {
+        self.inner.is_trimmable()
+    }
+
+    fn as_choice(&self) -> Option<&ChoiceQuestion> {
+        Some(self)
+    }
+}
+
 /// array_search operates over the choice values as strings; this projects the
 /// choices map's values into the string-keyed form the shim expects.
 fn choices_as_str(choices: &IndexMap<String, PhpMixed>) -> IndexMap<String, String> {
diff --git a/crates/shirabe-external-packages/src/symfony/console/question/confirmation_question.rs b/crates/shirabe-external-packages/src/symfony/console/question/confirmation_question.rs
index 5076d84..74039d0 100644
--- a/crates/shirabe-external-packages/src/symfony/console/question/confirmation_question.rs
+++ b/crates/shirabe-external-packages/src/symfony/console/question/confirmation_question.rs
@@ -1,6 +1,8 @@
 //! ref: composer/vendor/symfony/console/Question/ConfirmationQuestion.php
 
+use crate::symfony::console::exception::invalid_argument_exception::InvalidArgumentException;
 use crate::symfony::console::question::Question;
+use crate::symfony::console::question::QuestionInterface;
 use shirabe_php_shim::PhpMixed;
 
 /// Represents a yes/no question.
@@ -57,3 +59,55 @@ impl ConfirmationQuestion {
         })
     }
 }
+
+impl QuestionInterface for ConfirmationQuestion {
+    fn get_question(&self) -> &str {
+        self.inner.get_question()
+    }
+
+    fn get_default(&self) -> PhpMixed {
+        self.inner.get_default()
+    }
+
+    fn is_multiline(&self) -> bool {
+        self.inner.is_multiline()
+    }
+
+    fn is_hidden(&self) -> bool {
+        self.inner.is_hidden()
+    }
+
+    fn is_hidden_fallback(&self) -> bool {
+        self.inner.is_hidden_fallback()
+    }
+
+    fn get_autocompleter_values(&self) -> Option<Vec<PhpMixed>> {
+        self.inner.get_autocompleter_values()
+    }
+
+    fn get_autocompleter_callback(&self) -> Option<&(dyn Fn(&str) -> Option<Vec<PhpMixed>>)> {
+        self.inner.get_autocompleter_callback()
+    }
+
+    fn get_validator(
+        &self,
+    ) -> Option<&(dyn Fn(Option<PhpMixed>) -> Result<PhpMixed, InvalidArgumentException>)> {
+        self.inner.get_validator()
+    }
+
+    fn get_max_attempts(&self) -> Option<i64> {
+        self.inner.get_max_attempts()
+    }
+
+    fn get_normalizer(&self) -> Option<&(dyn Fn(PhpMixed) -> PhpMixed)> {
+        self.inner.get_normalizer()
+    }
+
+    fn is_trimmable(&self) -> bool {
+        self.inner.is_trimmable()
+    }
+
+    fn as_confirmation(&self) -> Option<&ConfirmationQuestion> {
+        Some(self)
+    }
+}
diff --git a/crates/shirabe-external-packages/src/symfony/console/question/mod.rs b/crates/shirabe-external-packages/src/symfony/console/question/mod.rs
index 06e0c2c..06d03b4 100644
--- a/crates/shirabe-external-packages/src/symfony/console/question/mod.rs
+++ b/crates/shirabe-external-packages/src/symfony/console/question/mod.rs
@@ -1,6 +1,6 @@
-pub mod choice_question;
-pub mod confirmation_question;
-pub mod question;
+mod choice_question;
+mod confirmation_question;
+mod question;
 
 pub use choice_question::*;
 pub use confirmation_question::*;
diff --git a/crates/shirabe-external-packages/src/symfony/console/question/question.rs b/crates/shirabe-external-packages/src/symfony/console/question/question.rs
index 9ec3aef..c93a71e 100644
--- a/crates/shirabe-external-packages/src/symfony/console/question/question.rs
+++ b/crates/shirabe-external-packages/src/symfony/console/question/question.rs
@@ -2,8 +2,53 @@
 
 use crate::symfony::console::exception::invalid_argument_exception::InvalidArgumentException;
 use crate::symfony::console::exception::logic_exception::LogicException;
+use crate::symfony::console::question::choice_question::ChoiceQuestion;
+use crate::symfony::console::question::confirmation_question::ConfirmationQuestion;
 use shirabe_php_shim::PhpMixed;
 
+/// Polymorphic boundary for the Symfony Console Question hierarchy.
+///
+/// PHP has no `QuestionInterface`; `Question` is a concrete class extended by
+/// `ChoiceQuestion`/`ConfirmationQuestion`. Modelling those subclasses as
+/// `inner: Question` composition loses subtype identity, so consumers that take
+/// a `Question` and run `instanceof` checks are expressed here as a trait whose
+/// `as_choice`/`as_confirmation` downcasts stand in for `instanceof`.
+pub trait QuestionInterface: std::fmt::Debug {
+    fn get_question(&self) -> &str;
+
+    fn get_default(&self) -> PhpMixed;
+
+    fn is_multiline(&self) -> bool;
+
+    fn is_hidden(&self) -> bool;
+
+    fn is_hidden_fallback(&self) -> bool;
+
+    fn get_autocompleter_values(&self) -> Option<Vec<PhpMixed>>;
+
+    fn get_autocompleter_callback(&self) -> Option<&(dyn Fn(&str) -> Option<Vec<PhpMixed>>)>;
+
+    fn get_validator(
+        &self,
+    ) -> Option<&(dyn Fn(Option<PhpMixed>) -> Result<PhpMixed, InvalidArgumentException>)>;
+
+    fn get_max_attempts(&self) -> Option<i64>;
+
+    fn get_normalizer(&self) -> Option<&(dyn Fn(PhpMixed) -> PhpMixed)>;
+
+    fn is_trimmable(&self) -> bool;
+
+    /// Models `$question instanceof ChoiceQuestion`.
+    fn as_choice(&self) -> Option<&ChoiceQuestion> {
+        None
+    }
+
+    /// Models `$question instanceof ConfirmationQuestion`.
+    fn as_confirmation(&self) -> Option<&ConfirmationQuestion> {
+        None
+    }
+}
+
 /// Represents a Question.
 pub struct Question {
     question: String,
@@ -275,3 +320,51 @@ impl Question {
         self
     }
 }
+
+impl QuestionInterface for Question {
+    fn get_question(&self) -> &str {
+        self.get_question()
+    }
+
+    fn get_default(&self) -> PhpMixed {
+        self.get_default()
+    }
+
+    fn is_multiline(&self) -> bool {
+        self.is_multiline()
+    }
+
+    fn is_hidden(&self) -> bool {
+        self.is_hidden()
+    }
+
+    fn is_hidden_fallback(&self) -> bool {
+        self.is_hidden_fallback()
+    }
+
+    fn get_autocompleter_values(&self) -> Option<Vec<PhpMixed>> {
+        self.get_autocompleter_values()
+    }
+
+    fn get_autocompleter_callback(&self) -> Option<&(dyn Fn(&str) -> Option<Vec<PhpMixed>>)> {
+        self.get_autocompleter_callback()
+    }
+
+    fn get_validator(
+        &self,
+    ) -> Option<&(dyn Fn(Option<PhpMixed>) -> Result<PhpMixed, InvalidArgumentException>)> {
+        self.get_validator()
+    }
+
+    fn get_max_attempts(&self) -> Option<i64> {
+        self.get_max_attempts()
+    }
+
+    fn get_normalizer(&self) -> Option<&(dyn Fn(PhpMixed) -> PhpMixed)> {
+        self.get_normalizer()
+    }
+
+    fn is_trimmable(&self) -> bool {
+        self.is_trimmable()
+    }
+}
diff --git a/crates/shirabe-external-packages/src/symfony/console/style/symfony_style.rs b/crates/shirabe-external-packages/src/symfony/console/style/symfony_style.rs
index 4b945b0..f445877 100644
--- a/crates/shirabe-external-packages/src/symfony/console/style/symfony_style.rs
+++ b/crates/shirabe-external-packages/src/symfony/console/style/symfony_style.rs
@@ -18,6 +18,7 @@ use crate::symfony::console::output::output_interface::OUTPUT_NORMAL;
 use crate::symfony::console::question::ChoiceQuestion;
 use crate::symfony::console::question::ConfirmationQuestion;
 use crate::symfony::console::question::Question;
+use crate::symfony::console::question::QuestionInterface;
 use crate::symfony::console::style::output_style::OutputStyle;
 use crate::symfony::console::style::style_interface::StyleInterface;
 use crate::symfony::console::terminal::Terminal;
@@ -211,7 +212,7 @@ impl SymfonyStyle {
         todo!()
     }
 
-    pub fn ask_question(&mut self, question: Question) -> PhpMixed {
+    pub fn ask_question(&mut self, question: &impl QuestionInterface) -> PhpMixed {
         if self.input.borrow().is_interactive() {
             self.auto_prepend_block();
         }
@@ -227,7 +228,7 @@ impl SymfonyStyle {
             self.question_helper
                 .as_mut()
                 .unwrap()
-                .ask(&mut *input, self.output.clone(), &question)
+                .ask(&mut *input, self.output.clone(), question)
         };
         // PHP `askQuestion` returns the answer directly; exceptions propagate. Phase B
         // collapses the double `Result` by panicking on either error.
@@ -669,7 +670,7 @@ impl StyleInterface for SymfonyStyle {
         );
         question.set_validator(Self::adapt_validator(validator));
 
-        self.ask_question(question)
+        self.ask_question(&question)
     }
 
     /// {@inheritdoc}
@@ -683,23 +684,18 @@ impl StyleInterface for SymfonyStyle {
         question.set_hidden(true);
         question.set_validator(Self::adapt_validator(validator));
 
-        self.ask_question(question)
+        self.ask_question(&question)
     }
 
     /// {@inheritdoc}
     fn confirm(&mut self, question: &str, default: bool) -> bool {
-        // PHP: return $this->askQuestion(new ConfirmationQuestion($question, $default));
-        // ConfirmationQuestion extends Question, but the ported type embeds a private
-        // `inner: Question` and cannot be passed to `ask_question(Question)`. The
-        // Question class hierarchy needs a trait/enum to dispatch polymorphically.
-        let _confirmation_question =
-            ConfirmationQuestion::new(question.to_string(), default, "/^y/i".to_string());
-        let answer = self.ask_question(todo!());
-        // PHP returns the bool answer from ConfirmationQuestion.
-        match answer {
-            PhpMixed::Bool(b) => b,
-            _ => todo!(),
-        }
+        let answer = self.ask_question(&ConfirmationQuestion::new(
+            question.to_string(),
+            default,
+            "/^y/i".to_string(),
+        ));
+
+        shirabe_php_shim::boolval(&answer)
     }
 
     /// {@inheritdoc}
@@ -713,21 +709,24 @@ impl StyleInterface for SymfonyStyle {
             let values =
                 shirabe_php_shim::array_flip(&PhpMixed::List(choices.iter().cloned().collect()));
             // $default = $values[$default] ?? $default;
-            let _ = values;
-            Some(default)
+            let resolved = match &values {
+                PhpMixed::Array(map) => map.get(&default.to_string()).cloned(),
+                _ => None,
+            };
+            Some(resolved.unwrap_or(default))
         } else {
             None
         };
 
         // PHP: return $this->askQuestion(new ChoiceQuestion($question, $choices, $default));
-        // ChoiceQuestion extends Question; see `confirm` for the polymorphism note.
         let choices_map: indexmap::IndexMap<String, PhpMixed> = choices
             .into_iter()
             .enumerate()
             .map(|(i, c)| (i.to_string(), c))
             .collect();
-        let _choice_question = ChoiceQuestion::new(question.to_string(), choices_map, default);
-        self.ask_question(todo!())
+        let choice_question = ChoiceQuestion::new(question.to_string(), choices_map, default)
+            .expect("choice() always provides at least one choice");
+        self.ask_question(&choice_question)
     }
 
     /// {@inheritdoc}