Support PowerSync extension when analyzing SQL

docs/docs/generation_options/index.md

@@ -194,6 +194,8 @@ We currently support the following extensions:
 - `spellfix1`: Assumes that the [spellfix1](https://www.sqlite.org/spellfix1.html)
   module is available. Note that this is not the case for most sqlite3 builds,
   including the ones shipping with `sqlite3_flutter_libs`.
+- `powersync`: Assumes that the PowerSync SQLite extension is available, allowing references to e.g.
+  `powersync_crud` in `CREATE TABLE` statements.
 
 ### Known custom functions
 

drift_dev/lib/src/analysis/driver/driver.dart

@@ -86,6 +86,8 @@ class DriftAnalysisDriver {
           if (options.hasModule(SqlModule.spellfix1))
             const Spellfix1Extension(),
           if (options.hasModule(SqlModule.geopoly)) const GeopolyExtension(),
+          if (options.hasModule(SqlModule.powersync))
+            const PowerSyncSqliteExtension(),
         ],
         version: options.sqliteVersion,
       ),

drift_dev/lib/src/analysis/options.dart

@@ -451,6 +451,10 @@ enum SqlModule {
   /// Enables the dbstat table providing insights into the disk state occupied
   /// by certain tables.
   dbstat,
+
+  /// Enables static analysis support for PowerSync, providing the
+  /// `powersync_crud` virtual table.
+  powersync,
 }
 
 /// The possible values for the case of the table and column names.

drift_dev/lib/src/generated/analysis/options.g.dart

@@ -211,6 +211,7 @@ const _$SqlModuleEnumMap = {
   SqlModule.spellfix1: 'spellfix1',
   SqlModule.geopoly: 'geopoly',
   SqlModule.dbstat: 'dbstat',
+  SqlModule.powersync: 'powersync',
 };
 
 const _$CaseFromDartToSqlEnumMap = {

drift_dev/pubspec.yaml

@@ -37,7 +37,7 @@ dependencies:
   # Drift-specific analysis and apis
   drift: ">=2.28.0 <2.29.0"
   sqlite3: ^2.4.6
-  sqlparser: ^0.41.2
+  sqlparser: ^0.42.0-0
 
   # Dart analysis
   # Note: When changing this to a lower bound of 8.x, please re-enable

drift_dev/test/analysis/resolver/drift/powersync_test.dart

@@ -0,0 +1,58 @@
+import 'package:drift_dev/src/analysis/options.dart';
+import 'package:test/test.dart';
+
+import '../../test_utils.dart';
+
+void main() {
+  test('can define triggers referencing powersync vtab', () async {
+    final state = await TestBackend.inTest({
+      'a|lib/main.drift': '''
+CREATE TABLE todo_lists (
+   id TEXT NOT NULL PRIMARY KEY,
+   created_by TEXT NOT NULL,
+   title TEXT NOT NULL,
+   content TEXT
+) STRICT;
+
+CREATE TRIGGER todo_lists_insert
+   AFTER INSERT ON todo_lists
+   FOR EACH ROW
+   BEGIN
+      INSERT INTO powersync_crud (op, id, type, data) VALUES ('PUT', NEW.id, 'todo_lists', json_object(
+         'created_by', NEW.created_by,
+         'title', NEW.title,
+         'content', NEW.content
+      ));
+   END;
+
+CREATE TRIGGER todo_lists_update
+   AFTER UPDATE ON todo_lists
+   FOR EACH ROW
+   BEGIN
+      SELECT CASE
+         WHEN (OLD.id != NEW.id)
+         THEN RAISE (FAIL, 'Cannot update id')
+      END;
+
+      -- TODO: You may want to replace the json_object with a powersync_diff call of the old and new values, or
+      -- use your own diff logic to avoid marking unchanged columns as updated.
+      INSERT INTO powersync_crud (op, id, type, data) VALUES ('PATCH', NEW.id, 'todo_lists', json_object(
+         'created_by', NEW.created_by,
+         'title', NEW.title,
+         'content', NEW.content
+      ));
+   END;
+
+CREATE TRIGGER todo_lists_delete
+   AFTER DELETE ON todo_lists
+   FOR EACH ROW
+   BEGIN
+      INSERT INTO powersync_crud (op, id, type) VALUES ('DELETE', OLD.id, 'todo_lists');
+   END;
+'''
+    }, options: DriftOptions.defaults(modules: [SqlModule.powersync]));
+
+    await state.analyze('package:a/main.drift');
+    state.expectNoErrors();
+  });
+}

sqlparser/CHANGELOG.md

@@ -1,6 +1,7 @@
-## 0.41.3-dev
+## 0.42.0-dev
 
 - Fix unresolved references in CTEs resolving against the scope of the main query.
+- Static analysis support for the PowerSync SQLite extension.
 
 ## 0.41.2
 

sqlparser/lib/sqlparser.dart

@@ -10,6 +10,7 @@ export 'src/engine/module/fts5.dart' show Fts5Extension, Fts5Table;
 export 'src/engine/module/geopoly.dart' show GeopolyExtension;
 export 'src/engine/module/json1.dart' show Json1Extension;
 export 'src/engine/module/math.dart' show BuiltInMathExtension;
+export 'src/engine/module/powersync.dart' show PowerSyncSqliteExtension;
 export 'src/engine/module/rtree.dart' show RTreeExtension;
 export 'src/engine/module/spellfix1.dart' show Spellfix1Extension;
 export 'src/engine/module/module.dart';

sqlparser/lib/src/engine/module/powersync.dart

@@ -0,0 +1,95 @@
+import 'package:sqlparser/src/analysis/types/types.dart';
+import 'package:sqlparser/src/ast/ast.dart';
+import 'package:sqlparser/src/engine/sql_engine.dart';
+
+import '../../analysis/analysis.dart';
+import 'module.dart';
+
+/// Provides static analysis support for the [PowerSync SQLite core extension].
+///
+/// This provides the `powersync_crud` eponymous virtual table to store local
+/// mutation as well as some JSON / UUID helper functions.
+///
+/// [PowerSync SQLite core extension]: https://github.com/powersync-ja/powersync-sqlite-core/
+final class PowerSyncSqliteExtension implements Extension {
+  const PowerSyncSqliteExtension();
+
+  @override
+  void register(SqlEngine engine) {
+    engine
+      ..registerTable(_powersyncCrudLegacy)
+      ..registerTable(_powersyncCrud)
+      ..registerFunctionHandler(const _PowerSyncFunctionHandler());
+  }
+}
+
+final class _PowerSyncFunctionHandler implements FunctionHandler {
+  const _PowerSyncFunctionHandler();
+
+  @override
+  Set<String> get functionNames => {
+        'powersync_diff', // (TEXT, TEXT) -> TEXT
+        'powersync_client_id', // () -> TEXT
+        'powersync_in_sync_operation', // () -> BOOLEAN
+        'gen_random_uuid', // () -> TEXT
+        'uuid', // () -> TEXT
+      };
+
+  @override
+  ResolveResult inferArgumentType(
+      TypeInferenceSession session, SqlInvocation call, Expression argument) {
+    switch (call.name.toLowerCase()) {
+      case 'powersync_diff':
+        return ResolveResult(_text);
+      default:
+        return ResolveResult.unknown();
+    }
+  }
+
+  @override
+  ResolveResult inferReturnType(TypeInferenceSession session,
+      SqlInvocation call, List<Typeable> expandedArgs) {
+    switch (call.name.toLowerCase()) {
+      case 'powersync_diff':
+      case 'powersync_client_id':
+      case 'gen_random_uuid':
+      case 'uuid':
+        return const ResolveResult(_text);
+      case 'powersync_in_sync_operation':
+        return const ResolveResult(ResolvedType.bool());
+      default:
+        return ResolveResult.unknown();
+    }
+  }
+
+  @override
+  void reportErrors(SqlInvocation call, AnalysisContext context) {}
+}
+
+/// `CREATE TABLE powersync_crud_(data TEXT, options INT HIDDEN);`
+///
+/// Source: https://github.com/powersync-ja/powersync-sqlite-core/blob/637fda0f1d84c46964736a4f8c59fab5ae27e304/crates/core/src/crud_vtab.rs#L26
+Table get _powersyncCrudLegacy {
+  return Table(name: 'powersync_crud', isVirtual: true, resolvedColumns: [
+    TableColumn('data', _text),
+    TableColumn('options', _int, isHidden: true),
+  ]);
+}
+
+/// `CREATE TABLE powersync_crud(op TEXT, id TEXT, type TEXT, data TEXT, old_values TEXT, metadata TEXT, options INT HIDDEN);`
+///
+/// Source: https://github.com/powersync-ja/powersync-sqlite-core/blob/637fda0f1d84c46964736a4f8c59fab5ae27e304/crates/core/src/crud_vtab.rs#L27C6-L27C126
+Table get _powersyncCrud {
+  return Table(name: 'powersync_crud', isVirtual: true, resolvedColumns: [
+    TableColumn('op', _text),
+    TableColumn('id', _text),
+    TableColumn('type', _text),
+    TableColumn('data', _text),
+    TableColumn('old_values', _text),
+    TableColumn('metadata', _text),
+    TableColumn('options', _int, isHidden: true),
+  ]);
+}
+
+const _text = ResolvedType(type: BasicType.text);
+const _int = ResolvedType(type: BasicType.int);

sqlparser/pubspec.yaml

@@ -1,6 +1,6 @@
 name: sqlparser
 description: Parses sqlite statements and performs static analysis on them
-version: 0.41.3-dev
+version: 0.42.0-dev
 homepage: https://github.com/simolus3/drift/tree/develop/sqlparser
 repository: https://github.com/simolus3/drift
 #homepage: https://drift.simonbinder.eu/

sqlparser/test/engine/module/powersync_test.dart

@@ -0,0 +1,99 @@
+import 'package:sqlparser/sqlparser.dart';
+import 'package:test/test.dart';
+
+import '../../analysis/data.dart';
+import '../../analysis/errors/utils.dart';
+
+void main() {
+  final options = EngineOptions(
+      version: SqliteVersion.current,
+      enabledExtensions: [const PowerSyncSqliteExtension()]);
+  late SqlEngine engine;
+
+  setUp(() {
+    engine = SqlEngine(options)..registerTableFromSql('''
+CREATE TABLE todo_lists (
+   id TEXT NOT NULL PRIMARY KEY,
+   created_by TEXT NOT NULL,
+   title TEXT NOT NULL,
+   content TEXT
+) STRICT;
+''');
+  });
+
+  group('crud vtab via triggers', () {
+    // This captures suggestions from https://docs.powersync.com/usage/use-case-examples/raw-tables#capture-local-writes-with-triggers
+    test('insert', () {
+      final result = engine.analyze('''
+CREATE TRIGGER todo_lists_insert
+   AFTER INSERT ON todo_lists
+   FOR EACH ROW
+   BEGIN
+      INSERT INTO powersync_crud (op, id, type, data) VALUES ('PUT', NEW.id, 'todo_lists', json_object(
+         'created_by', NEW.created_by,
+         'title', NEW.title,
+         'content', NEW.content
+      ));
+   END;
+''');
+
+      result.expectNoError();
+    });
+
+    test('update', () {
+      final result = engine.analyze('''
+CREATE TRIGGER todo_lists_update
+   AFTER UPDATE ON todo_lists
+   FOR EACH ROW
+   BEGIN
+      SELECT CASE
+         WHEN (OLD.id != NEW.id)
+         THEN RAISE (FAIL, 'Cannot update id')
+      END;
+
+      -- TODO: You may want to replace the json_object with a powersync_diff call of the old and new values, or
+      -- use your own diff logic to avoid marking unchanged columns as updated.
+      INSERT INTO powersync_crud (op, id, type, data) VALUES ('PATCH', NEW.id, 'todo_lists', json_object(
+         'created_by', NEW.created_by,
+         'title', NEW.title,
+         'content', NEW.content
+      ));
+   END;
+''');
+
+      result.expectNoError();
+    });
+
+    test('delete', () {
+      final result = engine.analyze('''
+CREATE TRIGGER todo_lists_delete
+   AFTER DELETE ON todo_lists
+   FOR EACH ROW
+   BEGIN
+      INSERT INTO powersync_crud (op, id, type) VALUES ('DELETE', OLD.id, 'todo_lists');
+   END;
+''');
+
+      result.expectNoError();
+    });
+  });
+
+  test('infers function return type', () {
+    final functions = {
+      "powersync_diff('{}', '{}')": BasicType.text,
+      'powersync_client_id()': BasicType.text,
+      'powersync_in_sync_operation()': BasicType.int,
+      'gen_random_uuid()': BasicType.text,
+      'uuid()': BasicType.text,
+    };
+
+    functions.forEach((call, type) {
+      final analyzed = engine.analyze('SELECT $call;');
+      analyzed.expectNoError();
+      final [column] = (analyzed.root as SelectStatement).resolvedColumns!;
+
+      expect(analyzed.typeOf(column).type?.type, type,
+          reason: '$call should resolve to $type');
+    });
+  });
+}