Remove redundant environment validation wrapper

Route the remaining validation convenience API through resolve_environment_selections and keep the resolver tests attached to the resolver itself.

Co-authored-by: Codex <noreply@openai.com>

codex-rs/core/src/environment_selection.rs

@@ -90,13 +90,6 @@ pub(crate) fn resolve_environment_selections(
     Ok(ResolvedTurnEnvironments { turn_environments })
 }
 
-pub(crate) fn validate_environment_selections(
-    environment_manager: &EnvironmentManager,
-    environments: &[TurnEnvironmentSelection],
-) -> CodexResult<()> {
-    resolve_environment_selections(environment_manager, environments).map(|_| ())
-}
-
 #[cfg(test)]
 mod tests {
     use codex_exec_server::ExecServerRuntimePaths;
@@ -145,11 +138,11 @@ mod tests {
     }
 
     #[tokio::test]
-    async fn validate_environment_selections_rejects_duplicate_ids() {
+    async fn resolve_environment_selections_rejects_duplicate_ids() {
         let cwd = AbsolutePathBuf::current_dir().expect("cwd");
         let manager = EnvironmentManager::default_for_tests();
 
-        let err = validate_environment_selections(
+        let err = resolve_environment_selections(
             &manager,
             &[
                 TurnEnvironmentSelection {

codex-rs/core/src/session/session.rs

@@ -2,6 +2,7 @@ use super::*;
 use crate::goals::GoalRuntimeState;
 use codex_protocol::permissions::FileSystemPath;
 use codex_protocol::permissions::FileSystemSpecialPath;
+use codex_protocol::protocol::TurnEnvironmentSelection;
 use tokio::sync::Semaphore;
 
 /// Context for an initialized model agent

codex-rs/core/src/thread_manager.rs

@@ -5,7 +5,6 @@ use crate::config::Config;
 use crate::config::ThreadStoreConfig;
 use crate::environment_selection::default_thread_environment_selections;
 use crate::environment_selection::resolve_environment_selections;
-use crate::environment_selection::validate_environment_selections;
 use crate::file_watcher::FileWatcher;
 use crate::mcp::McpManager;
 use crate::rollout::RolloutRecorder;
@@ -419,7 +418,8 @@ impl ThreadManager {
         &self,
         environments: &[TurnEnvironmentSelection],
     ) -> CodexResult<()> {
-        validate_environment_selections(self.state.environment_manager.as_ref(), environments)
+        resolve_environment_selections(self.state.environment_manager.as_ref(), environments)
+            .map(|_| ())
     }
 
     pub fn get_models_manager(&self) -> SharedModelsManager {