Resolve config paths during lenient projection

codex-rs/config/src/loader/mod.rs

@@ -15,6 +15,7 @@ use crate::diagnostics::ConfigError;
 use crate::diagnostics::config_error_from_toml;
 use crate::diagnostics::first_layer_config_error_from_entries as typed_first_layer_config_error_from_entries;
 use crate::diagnostics::io_error_from_config_error;
+use crate::lenient::deserialize_with_enum_warnings;
 use crate::merge::merge_toml_values;
 use crate::overrides::build_cli_overrides_layer;
 use crate::project_root_markers::default_project_root_markers;
@@ -870,9 +871,14 @@ pub fn resolve_relative_paths_in_config_toml(
     base_dir: &Path,
 ) -> io::Result<TomlValue> {
     // Use the serialize/deserialize round-trip to convert the
-    // `toml::Value` into a `ConfigToml` with `AbsolutePath
+    // `toml::Value` into a `ConfigToml` with `AbsolutePathBuf` fields resolved
+    // by the guard. Invalid enum values are ignored only for this typed
+    // projection; copy_shape_from_original preserves them in the raw layer so
+    // the final config load can still surface the startup warning.
     let _guard = AbsolutePathBufGuard::new(base_dir);
-    let Ok(resolved) = value_from_config_toml.clone().try_into::<ConfigToml>() else {
+    let Ok((_sanitized, resolved, _enum_warnings)) =
+        deserialize_with_enum_warnings::<ConfigToml>(value_from_config_toml.clone())
+    else {
         return Ok(value_from_config_toml);
     };
     drop(_guard);

codex-rs/core/src/config/config_loader_tests.rs

@@ -175,6 +175,39 @@ theme = "loudly"
     Ok(())
 }
 
+#[tokio::test]
+async fn invalid_enum_values_do_not_poison_relative_path_resolution() -> anyhow::Result<()> {
+    let tmp = tempdir().expect("tempdir");
+    std::fs::write(
+        tmp.path().join(CONFIG_TOML_FILE),
+        r#"
+model_instructions_file = "instructions.md"
+sandbox_mode = "make-it-so"
+"#,
+    )
+    .expect("write config");
+    std::fs::write(tmp.path().join("instructions.md"), "resolved instructions")
+        .expect("write instructions");
+
+    let config = ConfigBuilder::default()
+        .codex_home(tmp.path().to_path_buf())
+        .harness_overrides(ConfigOverrides {
+            cwd: Some(tmp.path().to_path_buf()),
+            ..Default::default()
+        })
+        .build()
+        .await?;
+
+    assert_eq!(
+        (config.base_instructions.as_deref(), config.startup_warnings,),
+        (
+            Some("resolved instructions"),
+            vec!["Ignoring invalid config value at sandbox_mode: \"make-it-so\"".to_string()],
+        )
+    );
+    Ok(())
+}
+
 #[tokio::test]
 async fn invalid_untagged_notification_value_does_not_delete_tui_table() -> anyhow::Result<()> {
     let tmp = tempdir().expect("tempdir");