Improved automated tests

Fixed bugs
Added support for in-memory database (without import/export)

lib/src/backend/impls/objectbox/backend/backend.dart

@@ -8,6 +8,7 @@ import 'dart:isolate';
 
 import 'package:collection/collection.dart';
 import 'package:flutter/services.dart';
+import 'package:meta/meta.dart';
 import 'package:path/path.dart' as path;
 import 'package:path_provider/path_provider.dart';
 
@@ -39,16 +40,20 @@ final class FMTCObjectBoxBackend implements FMTCBackend {
   /// specify the application group (of less than 20 chars). See
   /// [the ObjectBox docs](https://docs.objectbox.io/getting-started) for
   /// details.
+  ///
+  /// Avoid using [useInMemoryDatabase] outside of testing purposes.
   @override
   Future<void> initialise({
     String? rootDirectory,
     int maxDatabaseSize = 10000000,
     String? macosApplicationGroup,
+    @visibleForTesting bool useInMemoryDatabase = false,
   }) =>
       FMTCObjectBoxBackendInternal._instance.initialise(
         rootDirectory: rootDirectory,
         maxDatabaseSize: maxDatabaseSize,
         macosApplicationGroup: macosApplicationGroup,
+        useInMemoryDatabase: useInMemoryDatabase,
       );
 
   /// {@macro fmtc.backend.uninitialise}

lib/src/backend/impls/objectbox/backend/internal.dart

@@ -18,11 +18,10 @@ class _ObjectBoxBackendImpl implements FMTCObjectBoxBackendInternal {
   @override
   String get friendlyIdentifier => 'ObjectBox';
 
-  @override
-  Directory? rootDirectory;
-
   void get expectInitialised => _sendPort ?? (throw RootUnavailable());
 
+  late String rootDirectory;
+
   // Worker communication protocol storage
 
   SendPort? _sendPort;
@@ -117,16 +116,21 @@ class _ObjectBoxBackendImpl implements FMTCObjectBoxBackendInternal {
     required String? rootDirectory,
     required int maxDatabaseSize,
     required String? macosApplicationGroup,
+    required bool useInMemoryDatabase,
   }) async {
     if (_sendPort != null) throw RootAlreadyInitialised();
 
-    this.rootDirectory = await Directory(
-      path.join(
-        rootDirectory ??
-            (await getApplicationDocumentsDirectory()).absolute.path,
-        'fmtc',
-      ),
-    ).create(recursive: true);
+    if (useInMemoryDatabase) {
+      this.rootDirectory = Store.inMemoryPrefix + (rootDirectory ?? 'fmtc');
+    } else {
+      await Directory(
+        this.rootDirectory = path.join(
+          rootDirectory ??
+              (await getApplicationDocumentsDirectory()).absolute.path,
+          'fmtc',
+        ),
+      ).create(recursive: true);
+    }
 
     // Prepare to recieve `SendPort` from worker
     _workerResOneShot[0] = Completer();
@@ -200,7 +204,7 @@ class _ObjectBoxBackendImpl implements FMTCObjectBoxBackendInternal {
       _worker,
       (
         sendPort: receivePort.sendPort,
-        rootDirectory: this.rootDirectory!,
+        rootDirectory: this.rootDirectory,
         maxDatabaseSize: maxDatabaseSize,
         macosApplicationGroup: macosApplicationGroup,
         rootIsolateToken: ServicesBinding.rootIsolateToken!,
@@ -389,7 +393,7 @@ class _ObjectBoxBackendImpl implements FMTCObjectBoxBackendInternal {
     required String url,
   }) async =>
       (await _sendCmdOneShot(
-        type: _WorkerCmdType.deleteStore,
+        type: _WorkerCmdType.deleteTile,
         args: {'storeName': storeName, 'url': url},
       ))!['wasOrphan'];
 

lib/src/backend/impls/objectbox/backend/internal_worker.dart

@@ -65,7 +65,7 @@ enum _WorkerCmdType {
 Future<void> _worker(
   ({
     SendPort sendPort,
-    Directory rootDirectory,
+    String rootDirectory,
     int maxDatabaseSize,
     String? macosApplicationGroup,
     RootIsolateToken rootIsolateToken,
@@ -85,7 +85,7 @@ Future<void> _worker(
   late final Store root;
   try {
     root = await openStore(
-      directory: input.rootDirectory.absolute.path,
+      directory: input.rootDirectory,
       maxDBSizeInKB: input.maxDatabaseSize, // Defaults to 10 GB
       macosApplicationGroup: input.macosApplicationGroup,
     );
@@ -238,7 +238,11 @@ Future<void> _worker(
         root.close();
 
         if (cmd.args['deleteRoot'] == true) {
-          input.rootDirectory.deleteSync(recursive: true);
+          if (input.rootDirectory.startsWith(Store.inMemoryPrefix)) {
+            Store.removeDbFiles(input.rootDirectory);
+          } else {
+            Directory(input.rootDirectory).deleteSync(recursive: true);
+          }
         }
 
         sendRes(id: cmd.id);
@@ -248,8 +252,8 @@ Future<void> _worker(
         sendRes(
           id: cmd.id,
           data: {
-            'size': Store.dbFileSize(input.rootDirectory.absolute.path) /
-                1024, // Convert to KiB
+            'size':
+                Store.dbFileSize(input.rootDirectory) / 1024, // Convert to KiB
           },
         );
       case _WorkerCmdType.rootSize:
@@ -318,7 +322,7 @@ Future<void> _worker(
                   size: 0,
                   hits: 0,
                   misses: 0,
-                  metadataJson: '',
+                  metadataJson: '{}',
                 ),
                 mode: PutMode.insert,
               );
@@ -465,6 +469,8 @@ Future<void> _worker(
       case _WorkerCmdType.writeTile:
         final storeName = cmd.args['storeName']! as String;
         final url = cmd.args['url']! as String;
+
+        // TODO: `null` `bytes` is never actually used. Do we need to keep it?
         final bytes = cmd.args['bytes'] as Uint8List?;
 
         final tiles = root.box<ObjectBoxTile>();
@@ -509,10 +515,6 @@ Future<void> _worker(
                       ..length += 1
                       ..size += existingTile.bytes.lengthInBytes,
                   );
-                  updateRootStatistics(
-                    deltaLength: 1,
-                    deltaSize: existingTile.bytes.lengthInBytes,
-                  );
                 }
               case (false, false): // Existing tile, update required
                 final storesToUpdate = <String, ObjectBoxStore>{};
@@ -715,12 +717,12 @@ Future<void> _worker(
                 (throw StoreNotExists(storeName: storeName));
             query.close();
 
-            final Map<String, dynamic> json =
-                store.metadataJson == '' ? {} : jsonDecode(store.metadataJson);
-            json[key] = value;
-
             stores.put(
-              store..metadataJson = jsonEncode(json),
+              store
+                ..metadataJson = jsonEncode(
+                  (jsonDecode(store.metadataJson) as Map<String, dynamic>)
+                    ..[key] = value,
+                ),
               mode: PutMode.update,
             );
           },
@@ -743,13 +745,12 @@ Future<void> _worker(
                 (throw StoreNotExists(storeName: storeName));
             query.close();
 
-            final Map<String, dynamic> json =
-                store.metadataJson == '' ? {} : jsonDecode(store.metadataJson);
-            // ignore: cascade_invocations
-            json.addAll(kvs);
-
             stores.put(
-              store..metadataJson = jsonEncode(json),
+              store
+                ..metadataJson = jsonEncode(
+                  (jsonDecode(store.metadataJson) as Map<String, dynamic>)
+                    ..addAll(kvs),
+                ),
               mode: PutMode.update,
             );
           },
@@ -776,8 +777,8 @@ Future<void> _worker(
                 query.close();
 
                 final metadata =
-                    jsonDecode(store.metadataJson) as Map<String, String>;
-                final removedVal = metadata.remove(key);
+                    jsonDecode(store.metadataJson) as Map<String, dynamic>;
+                final removedVal = metadata.remove(key) as String?;
 
                 stores.put(
                   store..metadataJson = jsonEncode(metadata),
@@ -805,7 +806,7 @@ Future<void> _worker(
             query.close();
 
             stores.put(
-              store..metadataJson = jsonEncode(<String, String>{}),
+              store..metadataJson = '{}',
               mode: PutMode.update,
             );
           },
@@ -903,7 +904,7 @@ Future<void> _worker(
 
         final outputDir = path.dirname(outputPath);
 
-        if (outputDir == input.rootDirectory.absolute.path) {
+        if (path.equals(outputDir, input.rootDirectory)) {
           throw ExportInRootDirectoryForbidden();
         }
 
@@ -1028,8 +1029,7 @@ Future<void> _worker(
         final strategy = cmd.args['strategy'] as ImportConflictStrategy;
         final storesToImport = cmd.args['stores'] as List<String>?;
 
-        final importDir =
-            path.join(input.rootDirectory.absolute.path, 'import_tmp');
+        final importDir = path.join(input.rootDirectory, 'import_tmp');
         final importDirIO = Directory(importDir)..createSync();
 
         final importFile =
@@ -1437,8 +1437,7 @@ Future<void> _worker(
       case _WorkerCmdType.listImportableStores:
         final importPath = cmd.args['path']! as String;
 
-        final importDir =
-            path.join(input.rootDirectory.absolute.path, 'import_tmp');
+        final importDir = path.join(input.rootDirectory, 'import_tmp');
         final importDirIO = Directory(importDir)..createSync();
 
         final importFile =

lib/src/backend/interfaces/backend/internal.dart

@@ -2,9 +2,10 @@
 // A full license can be found at .\LICENSE
 
 import 'dart:async';
-import 'dart:io';
 import 'dart:typed_data';
 
+import 'package:meta/meta.dart';
+
 import '../../../../flutter_map_tile_caching.dart';
 import '../../export_internal.dart';
 
@@ -32,12 +33,6 @@ abstract interface class FMTCBackendInternal
   /// Generic description/name of this backend
   abstract final String friendlyIdentifier;
 
-  /// The filesystem directory in use
-  ///
-  /// May also be used as an indicator as to whether the root has been
-  /// initialised.
-  Directory? get rootDirectory;
-
   /// {@template fmtc.backend.realSize}
   /// Retrieve the actual total size of the database in KiBs
   ///
@@ -86,6 +81,8 @@ abstract interface class FMTCBackendInternal
   ///
   /// This operation cannot be undone! Ensure you confirm with the user that
   /// this action is expected.
+  ///
+  /// Does nothing if the store does not already exist.
   /// {@endtemplate}
   Future<void> deleteStore({
     required String storeName,
@@ -99,6 +96,8 @@ abstract interface class FMTCBackendInternal
   ///
   /// This operation cannot be undone! Ensure you confirm with the user that
   /// this action is expected.
+  ///
+  /// Does nothing if the store does not already exist.
   /// {@endtemplate}
   Future<void> resetStore({
     required String storeName,
@@ -173,6 +172,7 @@ abstract interface class FMTCBackendInternal
   ///  * `null` : if there was no existing tile
   ///  * `true` : if the tile itself could be deleted (it was orphaned)
   ///  * `false`: if the tile still belonged to at least one other store
+  @visibleForTesting
   Future<bool?> deleteTile({
     required String storeName,
     required String url,

lib/src/bulk_download/manager.dart

@@ -6,7 +6,6 @@ part of '../../flutter_map_tile_caching.dart';
 Future<void> _downloadManager(
   ({
     SendPort sendPort,
-    String rootDirectory,
     DownloadableRegion region,
     String storeName,
     int parallelThreads,
@@ -189,7 +188,6 @@ Future<void> _downloadManager(
           (
             sendPort: downloadThreadReceivePort.sendPort,
             storeName: input.storeName,
-            rootDirectory: input.rootDirectory,
             options: input.region.options,
             maxBufferLength: threadBufferLength,
             skipExistingTiles: input.skipExistingTiles,

lib/src/bulk_download/thread.dart

@@ -7,7 +7,6 @@ Future<void> _singleDownloadThread(
   ({
     SendPort sendPort,
     String storeName,
-    String rootDirectory,
     TileLayer options,
     int maxBufferLength,
     bool skipExistingTiles,

lib/src/store/download.dart

@@ -173,7 +173,6 @@ class DownloadManagement {
       _downloadManager,
       (
         sendPort: receivePort.sendPort,
-        rootDirectory: FMTCBackendAccess.internal.rootDirectory!.absolute.path,
         region: region,
         storeName: _storeDirectory.storeName,
         parallelThreads: parallelThreads,

lib/src/store/metadata.dart

@@ -33,7 +33,7 @@ class StoreMetadata {
           .setBulkMetadata(storeName: _storeName, kvs: kvs);
 
   /// {@macro fmtc.backend.removeMetadata}
-  Future<void> remove({
+  Future<String?> remove({
     required String key,
   }) =>
       FMTCBackendAccess.internal

lib/src/store/store.dart

@@ -82,4 +82,7 @@ class FMTCStore {
 
   @override
   int get hashCode => storeName.hashCode;
+
+  @override
+  String toString() => 'FMTCStore(storeName: $storeName)';
 }