investigation

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

Author: anakrish

bindings/csharp/Regorus/MemoryLimits.cs

@@ -75,7 +75,9 @@ public static void SetThreadFlushThresholdOverride(ulong? bytes)
 
                 if (result.data_type != RegorusDataType.Integer)
                 {
-                    throw new InvalidOperationException($"{errorContext}: native call did not return an integer");
+                    throw new InvalidOperationException(
+                        $"{errorContext}: native call returned {result.data_type} ({(int)result.data_type}) with bool_value={result.bool_value}"
+                    );
                 }
 
                 if (result.int_value < 0)

bindings/csharp/Regorus/NativeMethods.cs

@@ -560,6 +560,7 @@ internal unsafe partial struct RegorusResult
         /// Boolean value.
         /// Valid when data_type is Boolean.
         /// </summary>
+        [MarshalAs(UnmanagedType.I1)]
         public bool bool_value;
         /// <summary>
         /// Integer value.

bindings/ffi/src/limits.rs

@@ -130,3 +130,43 @@ fn feature_disabled(function: &str) -> RegorusResult {
         format!("{function} unavailable: regorus built without allocator-memory-limits feature"),
     )
 }
+
+#[cfg(test)]
+mod tests {
+    use super::{optional_u64_to_result, regorus_get_global_memory_limit, regorus_set_global_memory_limit};
+    use crate::common::{regorus_result_drop, RegorusDataType, RegorusStatus};
+
+    #[test]
+    fn optional_some_returns_integer() {
+        let result = optional_u64_to_result(Some(123));
+        assert!(result.bool_value);
+        assert!(matches!(result.data_type, RegorusDataType::Integer));
+        assert_eq!(result.int_value, 123);
+    }
+
+    #[test]
+    fn optional_none_returns_void() {
+        let result = optional_u64_to_result(None);
+        assert!(!result.bool_value);
+        assert!(matches!(result.data_type, RegorusDataType::None));
+        assert_eq!(result.int_value, 0);
+    }
+
+    #[test]
+    fn ffi_roundtrips_global_limit() {
+        let limit = 456_u64;
+        let result = regorus_set_global_memory_limit(limit, true);
+        assert!(matches!(result.status, RegorusStatus::Ok));
+        regorus_result_drop(result);
+
+        let result = regorus_get_global_memory_limit();
+        assert!(matches!(result.status, RegorusStatus::Ok));
+        assert!(result.bool_value);
+        assert!(matches!(result.data_type, RegorusDataType::Integer));
+        assert_eq!(result.int_value, 456);
+        regorus_result_drop(result);
+
+        let result = regorus_set_global_memory_limit(0, false);
+        regorus_result_drop(result);
+    }
+}