Make Rust managed bypass modes forward compatible

Replace the closed enum with an open string field and retain well-known policies as public constants.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: e98a14a6-7ad4-4cb6-b808-e56547701c19

Author: ellismg

rust/src/types.rs

@@ -1760,16 +1760,14 @@ pub struct CopilotExpAssignmentResponse {
     pub assignment_context: String,
 }
 
-/// Controls whether bypass-permissions mode is available in a managed session.
-#[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize)]
-#[serde(rename_all = "lowercase")]
-#[non_exhaustive]
-pub enum DisableBypassPermissionsMode {
-    /// Turn off bypass-permissions mode.
-    Disable,
+/// Well-known managed bypass-permissions policies.
+pub struct DisableBypassPermissionsModes;
+
+impl DisableBypassPermissionsModes {
+    /// Turn off bypass-permissions mode entirely.
+    pub const DISABLE: &'static str = "disable";
     /// Permit automatic bypass but block full allow-all.
-    #[serde(rename = "allow-auto-only")]
-    AllowAutoOnly,
+    pub const ALLOW_AUTO_ONLY: &'static str = "allow-auto-only";
 }
 
 /// Permission rules injected as a managed-settings layer at session bootstrap.
@@ -1784,10 +1782,11 @@ pub enum DisableBypassPermissionsMode {
 #[serde(rename_all = "camelCase")]
 #[non_exhaustive]
 pub struct ManagedSettingsPermissions {
-    /// Restricts bypass-permissions mode for the session. Serialized as
-    /// `disableBypassPermissionsMode`.
+    /// Restricts bypass-permissions mode for the session. See
+    /// [`DisableBypassPermissionsModes`] for well-known values. Unknown values
+    /// are forwarded so newer runtime policies fail closed.
     #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub disable_bypass_permissions_mode: Option<DisableBypassPermissionsMode>,
+    pub disable_bypass_permissions_mode: Option<String>,
     /// Tool-permission patterns that are always denied.
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub deny: Option<Vec<String>>,
@@ -1801,11 +1800,8 @@ pub struct ManagedSettingsPermissions {
 
 impl ManagedSettingsPermissions {
     /// Sets the bypass-permissions policy for this managed layer.
-    pub fn with_disable_bypass_permissions_mode(
-        mut self,
-        value: DisableBypassPermissionsMode,
-    ) -> Self {
-        self.disable_bypass_permissions_mode = Some(value);
+    pub fn with_disable_bypass_permissions_mode(mut self, value: impl Into<String>) -> Self {
+        self.disable_bypass_permissions_mode = Some(value.into());
         self
     }
 

rust/tests/session_test.rs

@@ -22,7 +22,7 @@ use github_copilot_sdk::session_events::{
 };
 use github_copilot_sdk::types::{
     CanvasProviderIdentity, CloudSessionOptions, CloudSessionRepository, CommandContext,
-    CommandDefinition, CommandHandler, DeliveryMode, DisableBypassPermissionsMode,
+    CommandDefinition, CommandHandler, DeliveryMode, DisableBypassPermissionsModes,
     ElicitationRequest, ElicitationResult, ExitPlanModeData, ExtensionInfo, ManagedSettings,
     ManagedSettingsPermissions, MessageOptions, PermissionDecisionContext,
     PermissionDecisionOutcome, PermissionDecisionSource, PermissionDecisionSurface, RequestId,
@@ -790,13 +790,18 @@ async fn create_session_sends_canvas_wire_fields() {
 
 #[test]
 fn managed_bypass_permissions_modes_use_wire_values() {
+    let known = ManagedSettingsPermissions::default()
+        .with_disable_bypass_permissions_mode(DisableBypassPermissionsModes::ALLOW_AUTO_ONLY);
     assert_eq!(
-        serde_json::to_value(DisableBypassPermissionsMode::Disable).unwrap(),
-        serde_json::json!("disable")
+        serde_json::to_value(known).unwrap()["disableBypassPermissionsMode"],
+        "allow-auto-only"
     );
+
+    let future = ManagedSettingsPermissions::default()
+        .with_disable_bypass_permissions_mode("future-fail-closed-mode");
     assert_eq!(
-        serde_json::to_value(DisableBypassPermissionsMode::AllowAutoOnly).unwrap(),
-        serde_json::json!("allow-auto-only")
+        serde_json::to_value(future).unwrap()["disableBypassPermissionsMode"],
+        "future-fail-closed-mode"
     );
 }
 
@@ -808,7 +813,7 @@ async fn create_and_resume_send_managed_settings_permissions() {
 
     let managed = ManagedSettings::default().with_permissions(
         ManagedSettingsPermissions::default()
-            .with_disable_bypass_permissions_mode(DisableBypassPermissionsMode::AllowAutoOnly)
+            .with_disable_bypass_permissions_mode(DisableBypassPermissionsModes::ALLOW_AUTO_ONLY)
             .with_deny(vec!["shell(rm*)".to_string()])
             .with_ask(vec!["write".to_string()])
             .with_allow(vec![]),