feat(diagnostics): split error and shutdown messages

libs/kaptan-log-derive/tests/ui/enum.rs

@@ -2,20 +2,30 @@ extern crate self as kaptan_log;
 
 use kaptan_log_derive::KaptanError;
 
-pub struct StaticErrorMessage(&'static str);
+pub struct StaticError {
+    path: &'static str,
+    additional_information: &'static str,
+}
 
-impl StaticErrorMessage {
+impl StaticError {
     pub const fn new(text: &'static str) -> Self {
-        Self(text)
+        Self {
+            path: text,
+            additional_information: "",
+        }
     }
 
-    pub const fn as_str(&self) -> &'static str {
-        self.0
+    pub const fn path(&self) -> &'static str {
+        self.path
+    }
+
+    pub const fn additional_information(&self) -> &'static str {
+        self.additional_information
     }
 }
 
 pub trait ErrorReport {
-    fn error_message(&self) -> &'static StaticErrorMessage;
+    fn static_error(&self) -> &'static StaticError;
 }
 
 #[derive(Debug, KaptanError)]
@@ -32,11 +42,11 @@ fn main() {
     fn assert_error<T: core::error::Error>() {}
     assert_error::<Generic<'_, u8>>();
     assert_eq!(
-        Generic::<u8>::Unit.error_message().as_str(),
+        Generic::<u8>::Unit.static_error().path(),
         concat!(module_path!(), "::Generic::Unit"),
     );
     assert_eq!(
-        Generic::Tuple(1_u8, 2).error_message().as_str(),
+        Generic::Tuple(1_u8, 2).static_error().path(),
         concat!(module_path!(), "::Generic::Tuple"),
     );
     let named: Generic<'_, u8> = Generic::Named { label: "test" };
@@ -44,4 +54,9 @@ fn main() {
         named.to_string(),
         concat!(module_path!(), "::Generic::Named"),
     );
+    assert_eq!(
+        named.static_error().additional_information(),
+        "",
+        "derives emit identity only; callers own optional context",
+    );
 }