CommandType (#12)

* working

* more consistent comments

Author: danylo-safonov-solid

example/lib/main.dart

@@ -16,7 +16,12 @@ Future<Response> fetch(Request _) async {
   );
   await client.end();
 
-  return Response(result.rows.map(rowToPrettyString).join('\n\n'));
+  return Response(
+    [
+      result.command == CommandType.select,
+      ...result.rows.map(rowToPrettyString),
+    ].join('\n\n'),
+  );
 }
 
 Future<QueryObjectResult<dynamic>> transaction(Transaction transaction) async {

lib/deno_postgres_interop.dart

@@ -2,9 +2,11 @@
 library;
 
 export 'src/client.dart';
+export 'src/command_type.dart';
 export 'src/isolation_level.dart';
 export 'src/query_client.dart';
 export 'src/query_object.dart' show QueryArguments;
 export 'src/query_object_result.dart';
+export 'src/query_result.dart';
 export 'src/transaction.dart';
 export 'src/transaction_options.dart';

lib/src/command_type.dart

@@ -0,0 +1,27 @@
+/// All sql commands.
+enum CommandType {
+  /// insert.
+  insert,
+
+  /// delete.
+  delete,
+
+  /// update.
+  update,
+
+  /// select.
+  select,
+
+  /// move.
+  move,
+
+  /// fetch.
+  fetch,
+
+  /// copy.
+  copy;
+
+  /// Parses a string containing an [CommandType] literal into its instance.
+  static CommandType parse(String string) =>
+      values.firstWhere((e) => e.name.toUpperCase() == string);
+}

lib/src/query.dart

@@ -0,0 +1,5 @@
+import 'dart:js_interop';
+
+/// [[email protected]/Query](https://deno.land/x/[email protected]/query/query.ts?s=Query).
+@JS()
+class Query<T> {}

lib/src/query_object_result.dart

@@ -1,11 +1,17 @@
 import 'dart:js_interop';
 import 'dart:js_util';
 
+import 'package:deno_postgres_interop/src/query.dart';
+import 'package:deno_postgres_interop/src/query_result.dart';
+
 /// [[email protected]/QueryObjectResult](https://deno.land/x/[email protected]/query/query.ts?s=QueryObjectResult).
 @JS()
-class QueryObjectResult<T> {
+class QueryObjectResult<T> extends QueryResult {
   /// [[email protected]/QueryObjectResult/columns](https://deno.land/x/[email protected]/query/query.ts?s=QueryObjectResult#prop_columns).
   external List<String>? get columns;
+
+  /// [[email protected]/QueryResult/constructor](https://deno.land/x/[email protected]/query/query.ts?s=QueryResult#ctor_0).
+  external factory QueryObjectResult(Query<dynamic> query);
 }
 
 /// [[email protected]/QueryObjectResult](https://deno.land/x/[email protected]/query/query.ts?s=QueryObjectResult).

lib/src/query_result.dart

@@ -0,0 +1,16 @@
+import 'dart:js_interop';
+import 'dart:js_util';
+
+import 'package:deno_postgres_interop/src/command_type.dart';
+
+/// [[email protected]/QueryResult](https://deno.land/x/[email protected]/query/query.ts?s=QueryResult).
+@JS()
+class QueryResult {}
+
+/// [[email protected]/QueryResult](https://deno.land/x/[email protected]/query/query.ts?s=QueryResult).
+extension QueryResultProps on QueryResult {
+  /// [[email protected]/QueryResult/command](https://deno.land/x/[email protected]/query/query.ts?s=QueryResult#prop_command).
+  CommandType get command => CommandType.parse(
+        getProperty(this, 'command'),
+      );
+}