Add collaboration modes test prompts (#9443)

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codex-rs/core/src/features.rs

@@ -100,6 +100,8 @@ pub enum Feature {
     Collab,
     /// Steer feature flag - when enabled, Enter submits immediately instead of queuing.
     Steer,
+    /// Enable collaboration modes (Plan, Pair Programming, Execute).
+    CollaborationModes,
 }
 
 impl Feature {
@@ -444,4 +446,10 @@ pub const FEATURES: &[FeatureSpec] = &[
         },
         default_enabled: false,
     },
+    FeatureSpec {
+        id: Feature::CollaborationModes,
+        key: "collaboration_modes",
+        stage: Stage::Experimental,
+        default_enabled: false,
+    },
 ];

codex-rs/core/src/models_manager/collaboration_mode_presets.rs

@@ -2,23 +2,34 @@ use codex_protocol::config_types::CollaborationMode;
 use codex_protocol::config_types::Settings;
 use codex_protocol::openai_models::ReasoningEffort;
 
+const COLLABORATION_MODE_PLAN: &str = include_str!("../../templates/collaboration_mode/plan.md");
+const COLLABORATION_MODE_PAIR_PROGRAMMING: &str =
+    include_str!("../../templates/collaboration_mode/pair_programming.md");
+const COLLABORATION_MODE_EXECUTE: &str =
+    include_str!("../../templates/collaboration_mode/execute.md");
+
 pub(super) fn builtin_collaboration_mode_presets() -> Vec<CollaborationMode> {
-    vec![plan_preset(), collaborate_preset(), execute_preset()]
+    vec![plan_preset(), pair_programming_preset(), execute_preset()]
+}
+
+#[cfg(any(test, feature = "test-support"))]
+pub fn test_builtin_collaboration_mode_presets() -> Vec<CollaborationMode> {
+    builtin_collaboration_mode_presets()
 }
 
 fn plan_preset() -> CollaborationMode {
     CollaborationMode::Plan(Settings {
         model: "gpt-5.2-codex".to_string(),
         reasoning_effort: Some(ReasoningEffort::Medium),
-        developer_instructions: None,
+        developer_instructions: Some(COLLABORATION_MODE_PLAN.to_string()),
     })
 }
 
-fn collaborate_preset() -> CollaborationMode {
-    CollaborationMode::Collaborate(Settings {
+fn pair_programming_preset() -> CollaborationMode {
+    CollaborationMode::PairProgramming(Settings {
         model: "gpt-5.2-codex".to_string(),
         reasoning_effort: Some(ReasoningEffort::Medium),
-        developer_instructions: None,
+        developer_instructions: Some(COLLABORATION_MODE_PAIR_PROGRAMMING.to_string()),
     })
 }
 
@@ -26,6 +37,6 @@ fn execute_preset() -> CollaborationMode {
     CollaborationMode::Execute(Settings {
         model: "gpt-5.2-codex".to_string(),
         reasoning_effort: Some(ReasoningEffort::XHigh),
-        developer_instructions: None,
+        developer_instructions: Some(COLLABORATION_MODE_EXECUTE.to_string()),
     })
 }

codex-rs/core/src/models_manager/mod.rs

@@ -3,3 +3,6 @@ pub mod collaboration_mode_presets;
 pub mod manager;
 pub mod model_info;
 pub mod model_presets;
+
+#[cfg(any(test, feature = "test-support"))]
+pub use collaboration_mode_presets::test_builtin_collaboration_mode_presets;