🧪 Liberate the tests from their inline prison

At last, the tests have been FREED from their cramped quarters in
history.rs and reducer.rs! They now reside in their own glorious
src/studio/tests/ kingdom where they can BREATHE and MULTIPLY.

No longer shall implementation code and test code share the same
file like some kind of CHAOS ZONE. Order has been restored!

But wait - there's MORE! I have exposed max_events as pub(crate)
so we can VERIFY the history trimming actually works. Trust no one.
Test EVERYTHING.

Added comprehensive reducer tests because EVERY. SINGLE. PATH.
must be covered: agent results, message navigation, edit modes,
error handling - NONE SHALL ESCAPE MY VALIDATION!

Author: hyperb1iss

src/studio/history.rs

@@ -93,7 +93,7 @@ pub struct History {
     events: VecDeque<HistoryEntry>,
 
     /// Maximum events to retain (prevents unbounded growth)
-    max_events: usize,
+    pub(crate) max_events: usize,
 
     /// Chat messages (persists across modes)
     chat_messages: Vec<ChatMessage>,
@@ -577,85 +577,3 @@ pub struct ModeContext {
     /// Related content (e.g., commit message being discussed)
     pub related_content: Option<String>,
 }
-
-// ═══════════════════════════════════════════════════════════════════════════════
-// Tests
-// ═══════════════════════════════════════════════════════════════════════════════
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_new_history() {
-        let history = History::new();
-        assert_eq!(history.event_count(), 0);
-        assert_eq!(history.chat_messages().len(), 0);
-    }
-
-    #[test]
-    fn test_add_chat_message() {
-        let mut history = History::new();
-
-        history.add_chat_message(ChatRole::User, "Hello, Iris!".to_string());
-        history.add_chat_message(ChatRole::Iris, "Hello! How can I help?".to_string());
-
-        assert_eq!(history.chat_messages().len(), 2);
-        assert_eq!(history.chat_messages()[0].role, ChatRole::User);
-        assert_eq!(history.chat_messages()[1].role, ChatRole::Iris);
-    }
-
-    #[test]
-    fn test_record_content() {
-        let mut history = History::new();
-
-        let msg = GeneratedMessage {
-            emoji: Some("✨".to_string()),
-            title: "Add new feature".to_string(),
-            message: "Implement the thing".to_string(),
-        };
-
-        history.record_content(
-            Mode::Commit,
-            ContentType::CommitMessage,
-            &ContentData::Commit(msg),
-            EventSource::Agent,
-            "initial_generation",
-        );
-
-        assert_eq!(
-            history.content_version_count(Mode::Commit, ContentType::CommitMessage),
-            1
-        );
-        assert!(
-            history
-                .latest_content(Mode::Commit, ContentType::CommitMessage)
-                .is_some()
-        );
-    }
-
-    #[test]
-    fn test_content_preview() {
-        let msg = GeneratedMessage {
-            emoji: Some("🔧".to_string()),
-            title: "Fix the bug".to_string(),
-            message: "Details here".to_string(),
-        };
-
-        let data = ContentData::Commit(msg);
-        assert!(data.preview(50).starts_with("🔧 Fix"));
-    }
-
-    #[test]
-    fn test_history_trimming() {
-        let mut history = History::new();
-        history.max_events = 10;
-
-        for i in 0..20 {
-            history.add_chat_message(ChatRole::User, format!("Message {}", i));
-        }
-
-        // Events should be trimmed, but chat messages aren't (different storage)
-        assert!(history.event_count() <= 10);
-    }
-}

src/studio/mod.rs

@@ -28,6 +28,9 @@ mod theme;
 // Submodules
 pub mod components;
 
+#[cfg(test)]
+mod tests;
+
 // Re-exports
 pub use app::{ExitResult, StudioApp, run_studio};
 pub use state::{Mode, StudioState};

src/studio/reducer.rs

@@ -1006,73 +1006,3 @@ fn reduce_mouse_event(
 
     effects
 }
-
-// ═══════════════════════════════════════════════════════════════════════════════
-// Tests
-// ═══════════════════════════════════════════════════════════════════════════════
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::config::Config;
-
-    fn test_state() -> StudioState {
-        StudioState::new(Config::default(), None)
-    }
-
-    #[test]
-    fn test_mode_switch() {
-        let mut state = test_state();
-        let mut history = History::new();
-
-        let effects = reduce(
-            &mut state,
-            StudioEvent::SwitchMode(Mode::Commit),
-            &mut history,
-        );
-
-        assert_eq!(state.active_mode, Mode::Commit);
-        assert!(!effects.is_empty()); // Should have LoadData effect
-    }
-
-    #[test]
-    fn test_focus_panel() {
-        let mut state = test_state();
-        let mut history = History::new();
-
-        let _ = reduce(
-            &mut state,
-            StudioEvent::FocusPanel(PanelId::Right),
-            &mut history,
-        );
-
-        assert_eq!(state.focused_panel, PanelId::Right);
-    }
-
-    #[test]
-    fn test_notify() {
-        let mut state = test_state();
-        let mut history = History::new();
-
-        let _ = reduce(
-            &mut state,
-            StudioEvent::Notify {
-                level: NotificationLevel::Success,
-                message: "Test notification".to_string(),
-            },
-            &mut history,
-        );
-
-        assert!(!state.notifications.is_empty());
-    }
-
-    #[test]
-    fn test_quit_produces_effect() {
-        let mut state = test_state();
-        let mut history = History::new();
-
-        let effects = reduce(&mut state, StudioEvent::Quit, &mut history);
-
-        assert!(effects.iter().any(|e| matches!(e, SideEffect::Quit)));
-    }
-}

src/studio/tests/history_tests.rs

@@ -0,0 +1,79 @@
+//! Tests for the History system
+
+use crate::studio::events::{ContentType, EventSource};
+use crate::studio::history::{ChatRole, ContentData, History};
+use crate::studio::state::Mode;
+use crate::types::GeneratedMessage;
+
+#[test]
+fn test_new_history() {
+    let history = History::new();
+    assert_eq!(history.event_count(), 0);
+    assert_eq!(history.chat_messages().len(), 0);
+}
+
+#[test]
+fn test_add_chat_message() {
+    let mut history = History::new();
+
+    history.add_chat_message(ChatRole::User, "Hello, Iris!".to_string());
+    history.add_chat_message(ChatRole::Iris, "Hello! How can I help?".to_string());
+
+    assert_eq!(history.chat_messages().len(), 2);
+    assert_eq!(history.chat_messages()[0].role, ChatRole::User);
+    assert_eq!(history.chat_messages()[1].role, ChatRole::Iris);
+}
+
+#[test]
+fn test_record_content() {
+    let mut history = History::new();
+
+    let msg = GeneratedMessage {
+        emoji: Some("✨".to_string()),
+        title: "Add new feature".to_string(),
+        message: "Implement the thing".to_string(),
+    };
+
+    history.record_content(
+        Mode::Commit,
+        ContentType::CommitMessage,
+        &ContentData::Commit(msg),
+        EventSource::Agent,
+        "initial_generation",
+    );
+
+    assert_eq!(
+        history.content_version_count(Mode::Commit, ContentType::CommitMessage),
+        1
+    );
+    assert!(
+        history
+            .latest_content(Mode::Commit, ContentType::CommitMessage)
+            .is_some()
+    );
+}
+
+#[test]
+fn test_content_preview() {
+    let msg = GeneratedMessage {
+        emoji: Some("🔧".to_string()),
+        title: "Fix the bug".to_string(),
+        message: "Details here".to_string(),
+    };
+
+    let data = ContentData::Commit(msg);
+    assert!(data.preview(50).starts_with("🔧 Fix"));
+}
+
+#[test]
+fn test_history_trimming() {
+    let mut history = History::new();
+    history.max_events = 10;
+
+    for i in 0..20 {
+        history.add_chat_message(ChatRole::User, format!("Message {}", i));
+    }
+
+    // Events should be trimmed, but chat messages aren't (different storage)
+    assert!(history.event_count() <= 10);
+}

src/studio/tests/mod.rs

@@ -0,0 +1,4 @@
+//! Tests for Iris Studio
+
+mod history_tests;
+mod reducer_tests;