chore: move types out of config.rs into config_types.rs (#1054)

`config.rs` is already quite long without these definitions. Since they
have no real dependencies of their own, let's move them to their own
file so `config.rs` can focus on the business logic of loading a config.

codex-rs/core/src/config.rs

@@ -1,6 +1,9 @@
 use crate::config_profile::ConfigProfile;
+use crate::config_types::History;
+use crate::config_types::McpServerConfig;
+use crate::config_types::Tui;
+use crate::config_types::UriBasedFileOpener;
 use crate::flags::OPENAI_DEFAULT_MODEL;
-use crate::mcp_server_config::McpServerConfig;
 use crate::model_provider_info::ModelProviderInfo;
 use crate::model_provider_info::built_in_model_providers;
 use crate::protocol::AskForApproval;
@@ -93,75 +96,6 @@ pub struct Config {
     pub tui: Tui,
 }
 
-/// Settings that govern if and what will be written to `~/.codex/history.jsonl`.
-#[derive(Deserialize, Debug, Clone, PartialEq, Default)]
-pub struct History {
-    /// If true, history entries will not be written to disk.
-    pub persistence: HistoryPersistence,
-
-    /// If set, the maximum size of the history file in bytes.
-    /// TODO(mbolin): Not currently honored.
-    pub max_bytes: Option<usize>,
-}
-
-#[derive(Deserialize, Debug, Copy, Clone, PartialEq, Default)]
-#[serde(rename_all = "kebab-case")]
-pub enum HistoryPersistence {
-    /// Save all history entries to disk.
-    #[default]
-    SaveAll,
-    /// Do not write history to disk.
-    None,
-}
-
-/// Collection of settings that are specific to the TUI.
-#[derive(Deserialize, Debug, Clone, PartialEq, Default)]
-pub struct Tui {
-    /// By default, mouse capture is enabled in the TUI so that it is possible
-    /// to scroll the conversation history with a mouse. This comes at the cost
-    /// of not being able to use the mouse to select text in the TUI.
-    /// (Most terminals support a modifier key to allow this. For example,
-    /// text selection works in iTerm if you hold down the `Option` key while
-    /// clicking and dragging.)
-    ///
-    /// Setting this option to `true` disables mouse capture, so scrolling with
-    /// the mouse is not possible, though the keyboard shortcuts e.g. `b` and
-    /// `space` still work. This allows the user to select text in the TUI
-    /// using the mouse without needing to hold down a modifier key.
-    pub disable_mouse_capture: bool,
-}
-
-#[derive(Deserialize, Debug, Copy, Clone, PartialEq)]
-pub enum UriBasedFileOpener {
-    #[serde(rename = "vscode")]
-    VsCode,
-
-    #[serde(rename = "vscode-insiders")]
-    VsCodeInsiders,
-
-    #[serde(rename = "windsurf")]
-    Windsurf,
-
-    #[serde(rename = "cursor")]
-    Cursor,
-
-    /// Option to disable the URI-based file opener.
-    #[serde(rename = "none")]
-    None,
-}
-
-impl UriBasedFileOpener {
-    pub fn get_scheme(&self) -> Option<&str> {
-        match self {
-            UriBasedFileOpener::VsCode => Some("vscode"),
-            UriBasedFileOpener::VsCodeInsiders => Some("vscode-insiders"),
-            UriBasedFileOpener::Windsurf => Some("windsurf"),
-            UriBasedFileOpener::Cursor => Some("cursor"),
-            UriBasedFileOpener::None => None,
-        }
-    }
-}
-
 /// Base config deserialized from ~/.codex/config.toml.
 #[derive(Deserialize, Debug, Clone, Default)]
 pub struct ConfigToml {
@@ -523,6 +457,8 @@ pub fn parse_sandbox_permission_with_base_path(
 #[cfg(test)]
 mod tests {
     #![allow(clippy::expect_used, clippy::unwrap_used)]
+    use crate::config_types::HistoryPersistence;
+
     use super::*;
     use pretty_assertions::assert_eq;
     use tempfile::TempDir;

codex-rs/core/src/config_types.rs

@@ -0,0 +1,88 @@
+//! Types used to define the fields of [`crate::config::Config`].
+
+// Note this file should generally be restricted to simple struct/enum
+// definitions that do not contain business logic.
+
+use std::collections::HashMap;
+
+use serde::Deserialize;
+
+#[derive(Deserialize, Debug, Clone, PartialEq)]
+pub struct McpServerConfig {
+    pub command: String,
+
+    #[serde(default)]
+    pub args: Vec<String>,
+
+    #[serde(default)]
+    pub env: Option<HashMap<String, String>>,
+}
+
+#[derive(Deserialize, Debug, Copy, Clone, PartialEq)]
+pub enum UriBasedFileOpener {
+    #[serde(rename = "vscode")]
+    VsCode,
+
+    #[serde(rename = "vscode-insiders")]
+    VsCodeInsiders,
+
+    #[serde(rename = "windsurf")]
+    Windsurf,
+
+    #[serde(rename = "cursor")]
+    Cursor,
+
+    /// Option to disable the URI-based file opener.
+    #[serde(rename = "none")]
+    None,
+}
+
+impl UriBasedFileOpener {
+    pub fn get_scheme(&self) -> Option<&str> {
+        match self {
+            UriBasedFileOpener::VsCode => Some("vscode"),
+            UriBasedFileOpener::VsCodeInsiders => Some("vscode-insiders"),
+            UriBasedFileOpener::Windsurf => Some("windsurf"),
+            UriBasedFileOpener::Cursor => Some("cursor"),
+            UriBasedFileOpener::None => None,
+        }
+    }
+}
+
+/// Settings that govern if and what will be written to `~/.codex/history.jsonl`.
+#[derive(Deserialize, Debug, Clone, PartialEq, Default)]
+pub struct History {
+    /// If true, history entries will not be written to disk.
+    pub persistence: HistoryPersistence,
+
+    /// If set, the maximum size of the history file in bytes.
+    /// TODO(mbolin): Not currently honored.
+    pub max_bytes: Option<usize>,
+}
+
+#[derive(Deserialize, Debug, Copy, Clone, PartialEq, Default)]
+#[serde(rename_all = "kebab-case")]
+pub enum HistoryPersistence {
+    /// Save all history entries to disk.
+    #[default]
+    SaveAll,
+    /// Do not write history to disk.
+    None,
+}
+
+/// Collection of settings that are specific to the TUI.
+#[derive(Deserialize, Debug, Clone, PartialEq, Default)]
+pub struct Tui {
+    /// By default, mouse capture is enabled in the TUI so that it is possible
+    /// to scroll the conversation history with a mouse. This comes at the cost
+    /// of not being able to use the mouse to select text in the TUI.
+    /// (Most terminals support a modifier key to allow this. For example,
+    /// text selection works in iTerm if you hold down the `Option` key while
+    /// clicking and dragging.)
+    ///
+    /// Setting this option to `true` disables mouse capture, so scrolling with
+    /// the mouse is not possible, though the keyboard shortcuts e.g. `b` and
+    /// `space` still work. This allows the user to select text in the TUI
+    /// using the mouse without needing to hold down a modifier key.
+    pub disable_mouse_capture: bool,
+}

codex-rs/core/src/lib.rs

@@ -13,6 +13,7 @@ pub use codex::Codex;
 pub mod codex_wrapper;
 pub mod config;
 pub mod config_profile;
+pub mod config_types;
 mod conversation_history;
 pub mod error;
 pub mod exec;
@@ -22,7 +23,6 @@ mod is_safe_command;
 #[cfg(target_os = "linux")]
 pub mod landlock;
 mod mcp_connection_manager;
-pub mod mcp_server_config;
 mod mcp_tool_call;
 mod message_history;
 mod model_provider_info;

codex-rs/core/src/mcp_connection_manager.rs

@@ -19,7 +19,7 @@ use mcp_types::Tool;
 use tokio::task::JoinSet;
 use tracing::info;
 
-use crate::mcp_server_config::McpServerConfig;
+use crate::config_types::McpServerConfig;
 
 /// Delimiter used to separate the server name from the tool name in a fully
 /// qualified tool name.

codex-rs/core/src/mcp_server_config.rs

@@ -1,14 +0,0 @@
-use std::collections::HashMap;
-
-use serde::Deserialize;
-
-#[derive(Deserialize, Debug, Clone, PartialEq)]
-pub struct McpServerConfig {
-    pub command: String,
-
-    #[serde(default)]
-    pub args: Vec<String>,
-
-    #[serde(default)]
-    pub env: Option<HashMap<String, String>>,
-}

codex-rs/core/src/message_history.rs

@@ -28,7 +28,7 @@ use tokio::io::AsyncReadExt;
 use uuid::Uuid;
 
 use crate::config::Config;
-use crate::config::HistoryPersistence;
+use crate::config_types::HistoryPersistence;
 
 #[cfg(unix)]
 use std::os::unix::fs::OpenOptionsExt;

codex-rs/tui/src/markdown.rs

@@ -1,5 +1,5 @@
 use codex_core::config::Config;
-use codex_core::config::UriBasedFileOpener;
+use codex_core::config_types::UriBasedFileOpener;
 use ratatui::text::Line;
 use ratatui::text::Span;
 use std::borrow::Cow;