From 8f6ec2ec5c3ba8ab33126ec79de7702835592902 Mon Sep 17 00:00:00 2001
From: Aaron Andersen <aaron@fosslib.net>
Date: Mon, 5 Jan 2026 20:57:51 -0500
Subject: [PATCH] Fix path coercion by calling eval_state_builder_load()

Without this call, settings from the global Nix configuration are never
loaded, leaving readOnlyMode = true (the default). This prevents Nix
from adding paths to the store during evaluation, causing errors like:

  error: path '/some/local/path' does not exist

This fix loads global settings before creating the EvalState, enabling
path coercion for local file references.
---
 nix-bindings-expr/src/eval_state.rs | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/nix-bindings-expr/src/eval_state.rs b/nix-bindings-expr/src/eval_state.rs
index 7d0808c..6fdedab 100644
--- a/nix-bindings-expr/src/eval_state.rs
+++ b/nix-bindings-expr/src/eval_state.rs
@@ -288,6 +288,15 @@ impl EvalStateBuilder {
 
         let mut context = Context::new();
 
+        // Load settings from global configuration (including readOnlyMode = false).
+        // This is necessary for path coercion to work (adding files to the store).
+        unsafe {
+            check_call!(raw::eval_state_builder_load(
+                &mut context,
+                self.eval_state_builder
+            ))?;
+        }
+
         // Note: these raw C string pointers borrow from self.lookup_path
         let mut lookup_path: Vec<*const c_char> = self
             .lookup_path