Resolve aliased columns

extras/integration_tests/README.md

@@ -17,5 +17,7 @@ communicates with an app to verify behavior of widgets. As we want to run the wh
 on a device, we instead put the test files into `flutter_db/lib` and run them with
 `flutter run`. That works, but we don't get an output format that is machine readable.
 Please create an issue if you know a better way, thanks!
+TODO: https://github.com/tomaszpolanski/flutter-presentations/blob/master/lib/test_driver/test_runner.dart
+looks promising
 
 That is also why these tests are not running automatically.

sqlparser/lib/src/analysis/steps/column_resolver.dart

@@ -80,14 +80,16 @@ class ColumnResolver extends RecursiveVisitor<void> {
         }
       } else if (resultColumn is ExpressionResultColumn) {
         final name = _nameOfResultColumn(resultColumn);
-        usedColumns.add(
-          ExpressionColumn(name: name, expression: resultColumn.expression),
-        );
+        final column =
+            ExpressionColumn(name: name, expression: resultColumn.expression);
+
+        availableColumns.add(column);
+        usedColumns.add(column);
       }
     }
 
     s.resolvedColumns = usedColumns;
-    s.scope.availableColumns = availableColumns;
+    scope.availableColumns = availableColumns;
   }
 
   String _nameOfResultColumn(ExpressionResultColumn c) {

sqlparser/test/analysis/reference_resolver_test.dart

@@ -1,6 +1,8 @@
+import 'package:sqlparser/src/utils/ast_equality.dart';
 import 'package:test/test.dart';
 import 'package:sqlparser/sqlparser.dart';
 
+import '../parser/utils.dart';
 import 'data.dart';
 
 void main() {
@@ -34,4 +36,26 @@ void main() {
     expect((secondColumn.expression as Reference).resolved, content);
     expect(from.resolved, demoTable);
   });
+
+  test('resolves the column for order by clauses', () {
+    final engine = SqlEngine()..registerTable(demoTable);
+
+    final context = engine
+        .analyze('SELECT d.content, 3 * d.id AS t FROM demo AS d ORDER BY t');
+
+    expect(context.errors, isEmpty);
+
+    final select = context.root as SelectStatement;
+    final orderingTerm = select.orderBy.terms.single.expression as Reference;
+    final resolved = orderingTerm.resolved as ExpressionColumn;
+
+    enforceEqual(
+      resolved.expression,
+      BinaryExpression(
+        NumericLiteral(3, token(TokenType.numberLiteral)),
+        token(TokenType.star),
+        Reference(tableName: 'd', columnName: 'id'),
+      ),
+    );
+  });
 }