feat: improve last_error and cffi_wrapper

omrf/tests/last_error.rs

@@ -0,0 +1,76 @@
+//! Integration tests for the `last_error` module.
+
+use sarasacw_omrf::last_error::{self, CError, CERROR_OK, CStrPtr};
+use thiserror::Error;
+
+#[derive(Debug, Error)]
+enum TestErr {
+    #[error("boom error")]
+    Boom,
+    #[error("bad\x00value")]
+    WithNul,
+}
+
+impl From<TestErr> for CError {
+    fn from(e: TestErr) -> Self {
+        match e {
+            TestErr::Boom => 7,
+            TestErr::WithNul => 9,
+        }
+    }
+}
+
+fn parse_cstr(ptr: CStrPtr) -> String {
+    assert!(!ptr.is_null());
+    unsafe { std::ffi::CStr::from_ptr(ptr) }
+        .to_string_lossy()
+        .into_owned()
+}
+
+#[test]
+fn fresh_state_is_absolute_success() {
+    last_error::clear_last_error();
+    assert!(!last_error::has_last_message());
+    assert_eq!(last_error::get_error_code(), CERROR_OK);
+    assert_eq!(parse_cstr(last_error::get_error_message()), "");
+}
+
+#[test]
+fn set_records_code_and_message() {
+    last_error::clear_last_error();
+    last_error::set_last_error(TestErr::Boom);
+    assert!(last_error::has_last_message());
+    assert_eq!(last_error::get_error_code(), 7);
+    assert_eq!(parse_cstr(last_error::get_error_message()), "boom error");
+}
+
+#[test]
+fn clear_resets_to_absolute_success() {
+    last_error::set_last_error(TestErr::Boom);
+    assert!(last_error::has_last_message());
+    last_error::clear_last_error();
+    assert!(!last_error::has_last_message());
+    assert_eq!(last_error::get_error_code(), CERROR_OK);
+    assert_eq!(parse_cstr(last_error::get_error_message()), "");
+}
+
+#[test]
+fn interior_nul_in_message_is_sanitized() {
+    last_error::clear_last_error();
+    last_error::set_last_error(TestErr::WithNul);
+    assert_eq!(last_error::get_error_code(), 9);
+    let msg = parse_cstr(last_error::get_error_message());
+    assert!(!msg.contains('\0'));
+    assert!(msg.contains("bad"));
+    assert!(msg.contains("value"));
+}
+
+#[test]
+fn overwriting_replaces_previous_state() {
+    last_error::clear_last_error();
+    last_error::set_last_error(TestErr::Boom);
+    last_error::set_last_error(TestErr::WithNul);
+    assert_eq!(last_error::get_error_code(), 9);
+    let msg = parse_cstr(last_error::get_error_message());
+    assert!(!msg.contains("boom"));
+}