Add hermetic coverage for service boundaries

crates/remora-worker/src/client.rs

@@ -250,3 +250,69 @@ fn generated_id(prefix: char) -> OpaqueId {
     }
     OpaqueId::parse(value).expect("generated identifier is valid")
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn response(status: StatusCode) -> Response {
+        http::Response::builder()
+            .status(status)
+            .body(String::new())
+            .unwrap()
+            .into()
+    }
+
+    #[test]
+    fn classifies_statuses() {
+        assert!(classify(response(StatusCode::NO_CONTENT)).is_ok());
+        assert!(matches!(
+            classify(response(StatusCode::BAD_REQUEST)),
+            Err(WorkerError::InvalidRequest)
+        ));
+        for status in [StatusCode::UNAUTHORIZED, StatusCode::FORBIDDEN] {
+            assert!(matches!(
+                classify(response(status)),
+                Err(WorkerError::Unauthenticated)
+            ));
+        }
+        assert!(matches!(
+            classify(response(StatusCode::CONFLICT)),
+            Err(WorkerError::PreconditionFailed)
+        ));
+        for status in [
+            StatusCode::NOT_FOUND,
+            StatusCode::TOO_MANY_REQUESTS,
+            StatusCode::SERVICE_UNAVAILABLE,
+        ] {
+            assert!(matches!(
+                classify(response(status)),
+                Err(WorkerError::ApiUnavailable)
+            ));
+        }
+    }
+
+    #[test]
+    fn validates_base_url() {
+        let client = Client::new();
+        let valid = WorkerApiClient::new("https://api.example.test/", client.clone()).unwrap();
+        assert_eq!(valid.base_url, "https://api.example.test");
+        for url in ["http://api.example.test", "https://", "not-a-url"] {
+            assert!(matches!(
+                WorkerApiClient::new(url, client.clone()),
+                Err(WorkerError::InvalidConfiguration)
+            ));
+        }
+    }
+
+    #[test]
+    fn ids_are_unique() {
+        let operation = operation_id();
+        let second = operation_id();
+        let incarnation = incarnation_id();
+        assert!(operation.as_str().starts_with('o'));
+        assert!(incarnation.as_str().starts_with('w'));
+        assert_ne!(operation, second);
+        assert_ne!(operation, incarnation);
+    }
+}