chore: add update for test_message_schema (#286)

Author: jokemanfire

crates/rmcp/tests/test_message_schema.rs

@@ -2,39 +2,71 @@ mod tests {
     use rmcp::model::{ClientJsonRpcMessage, ServerJsonRpcMessage};
     use schemars::schema_for;
 
+    fn compare_schemas(name: &str, actual: &str, expected_file: &str) {
+        let expected = match std::fs::read_to_string(expected_file) {
+            Ok(content) => content,
+            Err(e) => {
+                panic!(
+                    "Failed to read expected schema file {}: {}",
+                    expected_file, e
+                );
+            }
+        };
+
+        let actual_json: serde_json::Value =
+            serde_json::from_str(actual).expect("Failed to parse actual schema as JSON");
+        let expected_json: serde_json::Value =
+            serde_json::from_str(&expected).expect("Failed to parse expected schema as JSON");
+
+        if actual_json == expected_json {
+            println!("{} schema matches expected", name);
+            return;
+        }
+
+        // Write current schema to file for comparison
+        let current_file = expected_file.replace(".json", "_current.json");
+        std::fs::write(&current_file, actual).expect("Failed to write current schema");
+
+        println!("{} schema differs from expected", name);
+        println!("Expected: {}", expected_file);
+        println!("Current: {}", current_file);
+        println!(
+            "Run 'diff {} {}' to see differences",
+            expected_file, current_file
+        );
+
+        // UPDATE_SCHEMA=1 cargo test -p rmcp --test test_message_schema --features="server client schemars"
+        if std::env::var("UPDATE_SCHEMA").is_ok() {
+            println!("UPDATE_SCHEMA is set, updating expected file");
+            std::fs::write(expected_file, actual).expect("Failed to update expected schema file");
+            println!("Updated {}", expected_file);
+        } else {
+            println!("Set UPDATE_SCHEMA=1 to auto-update expected schemas");
+            panic!("Schema validation failed");
+        }
+    }
+
     #[test]
     fn test_client_json_rpc_message_schema() {
         let schema = schema_for!(ClientJsonRpcMessage);
-        let schema_str = serde_json::to_string_pretty(&schema).unwrap();
-        let expected = std::fs::read_to_string(
+        let schema_str = serde_json::to_string_pretty(&schema).expect("Failed to serialize schema");
+
+        compare_schemas(
+            "ClientJsonRpcMessage",
+            &schema_str,
             "tests/test_message_schema/client_json_rpc_message_schema.json",
-        )
-        .unwrap();
-
-        // Parse both strings to JSON values for more robust comparison
-        let schema_json: serde_json::Value = serde_json::from_str(&schema_str).unwrap();
-        let expected_json: serde_json::Value = serde_json::from_str(&expected).unwrap();
-        assert_eq!(
-            schema_json, expected_json,
-            "Schema generation for ClientJsonRpcMessage should match expected output"
         );
     }
 
     #[test]
     fn test_server_json_rpc_message_schema() {
         let schema = schema_for!(ServerJsonRpcMessage);
-        let schema_str = serde_json::to_string_pretty(&schema).unwrap();
-        let expected = std::fs::read_to_string(
+        let schema_str = serde_json::to_string_pretty(&schema).expect("Failed to serialize schema");
+
+        compare_schemas(
+            "ServerJsonRpcMessage",
+            &schema_str,
             "tests/test_message_schema/server_json_rpc_message_schema.json",
-        )
-        .unwrap();
-
-        // Parse both strings to JSON values for more robust comparison
-        let schema_json: serde_json::Value = serde_json::from_str(&schema_str).unwrap();
-        let expected_json: serde_json::Value = serde_json::from_str(&expected).unwrap();
-        assert_eq!(
-            schema_json, expected_json,
-            "Schema generation for ServerJsonRpcMessage should match expected output"
         );
     }
 }