[router] add ut for worker and errors (#8170)

sgl-router/src/core/error.rs

@@ -55,3 +55,182 @@ impl From<reqwest::Error> for WorkerError {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::error::Error;
+
+    #[test]
+    fn test_health_check_failed_display() {
+        let error = WorkerError::HealthCheckFailed {
+            url: "http://worker1:8080".to_string(),
+            reason: "Connection refused".to_string(),
+        };
+        assert_eq!(
+            error.to_string(),
+            "Health check failed for worker http://worker1:8080: Connection refused"
+        );
+    }
+
+    #[test]
+    fn test_worker_not_found_display() {
+        let error = WorkerError::WorkerNotFound {
+            url: "http://worker2:8080".to_string(),
+        };
+        assert_eq!(error.to_string(), "Worker not found: http://worker2:8080");
+    }
+
+    #[test]
+    fn test_invalid_configuration_display() {
+        let error = WorkerError::InvalidConfiguration {
+            message: "Missing port number".to_string(),
+        };
+        assert_eq!(
+            error.to_string(),
+            "Invalid worker configuration: Missing port number"
+        );
+    }
+
+    #[test]
+    fn test_network_error_display() {
+        let error = WorkerError::NetworkError {
+            url: "http://worker3:8080".to_string(),
+            error: "Timeout after 30s".to_string(),
+        };
+        assert_eq!(
+            error.to_string(),
+            "Network error for worker http://worker3:8080: Timeout after 30s"
+        );
+    }
+
+    #[test]
+    fn test_worker_at_capacity_display() {
+        let error = WorkerError::WorkerAtCapacity {
+            url: "http://worker4:8080".to_string(),
+        };
+        assert_eq!(error.to_string(), "Worker at capacity: http://worker4:8080");
+    }
+
+    #[test]
+    fn test_worker_error_implements_std_error() {
+        let error = WorkerError::WorkerNotFound {
+            url: "http://test".to_string(),
+        };
+        // Verify it implements Error trait
+        let _: &dyn Error = &error;
+        assert!(error.source().is_none());
+    }
+
+    #[test]
+    fn test_error_send_sync() {
+        fn assert_send_sync<T: Send + Sync>() {}
+        assert_send_sync::<WorkerError>();
+    }
+
+    #[test]
+    fn test_worker_result_type_alias() {
+        // Test Ok variant
+        let result: WorkerResult<i32> = Ok(42);
+        assert!(result.is_ok());
+        assert_eq!(result.unwrap(), 42);
+
+        // Test Err variant
+        let error = WorkerError::WorkerNotFound {
+            url: "test".to_string(),
+        };
+        let result: WorkerResult<i32> = Err(error);
+        assert!(result.is_err());
+    }
+
+    #[test]
+    fn test_empty_url_handling() {
+        // Test empty URLs in error variants
+        let error1 = WorkerError::HealthCheckFailed {
+            url: "".to_string(),
+            reason: "No connection".to_string(),
+        };
+        assert_eq!(
+            error1.to_string(),
+            "Health check failed for worker : No connection"
+        );
+
+        let error2 = WorkerError::NetworkError {
+            url: "".to_string(),
+            error: "DNS failure".to_string(),
+        };
+        assert_eq!(error2.to_string(), "Network error for worker : DNS failure");
+
+        let error3 = WorkerError::WorkerNotFound {
+            url: "".to_string(),
+        };
+        assert_eq!(error3.to_string(), "Worker not found: ");
+    }
+
+    #[test]
+    fn test_special_characters_in_messages() {
+        // Test with special characters
+        let error = WorkerError::InvalidConfiguration {
+            message: "Invalid JSON: {\"error\": \"test\"}".to_string(),
+        };
+        assert_eq!(
+            error.to_string(),
+            "Invalid worker configuration: Invalid JSON: {\"error\": \"test\"}"
+        );
+
+        // Test with unicode
+        let error2 = WorkerError::HealthCheckFailed {
+            url: "http://测试:8080".to_string(),
+            reason: "连接被拒绝".to_string(),
+        };
+        assert_eq!(
+            error2.to_string(),
+            "Health check failed for worker http://测试:8080: 连接被拒绝"
+        );
+    }
+
+    #[test]
+    fn test_very_long_error_messages() {
+        let long_message = "A".repeat(10000);
+        let error = WorkerError::InvalidConfiguration {
+            message: long_message.clone(),
+        };
+        let display = error.to_string();
+        assert!(display.contains(&long_message));
+        assert_eq!(
+            display.len(),
+            "Invalid worker configuration: ".len() + long_message.len()
+        );
+    }
+
+    // Mock reqwest error for testing conversion
+    #[test]
+    fn test_reqwest_error_conversion() {
+        // Test that NetworkError is the correct variant
+        let network_error = WorkerError::NetworkError {
+            url: "http://example.com".to_string(),
+            error: "connection timeout".to_string(),
+        };
+
+        match network_error {
+            WorkerError::NetworkError { url, error } => {
+                assert_eq!(url, "http://example.com");
+                assert_eq!(error, "connection timeout");
+            }
+            _ => panic!("Expected NetworkError variant"),
+        }
+    }
+
+    #[test]
+    fn test_error_equality() {
+        // WorkerError doesn't implement PartialEq, but we can test that
+        // the same error construction produces the same display output
+        let error1 = WorkerError::WorkerNotFound {
+            url: "http://test".to_string(),
+        };
+        let error2 = WorkerError::WorkerNotFound {
+            url: "http://test".to_string(),
+        };
+        assert_eq!(error1.to_string(), error2.to_string());
+    }
+}