Override default macOS SQLite for tests (#99)

* Override default macOS sqlite db for tests

* Update to use flutter test rather than dart test

* Added documentation

Author: mugikhan

melos.yaml

@@ -31,7 +31,7 @@ scripts:
 
   test:
     description: Run tests in a specific package.
-    run: dart test
+    run: flutter test
     exec:
       concurrency: 1
     packageFilters:

packages/powersync/lib/src/open_factory.dart

@@ -79,13 +79,22 @@ class PowerSyncOpenFactory extends DefaultSqliteOpenFactory {
   }
 
   void enableExtension() {
-    var powersyncLib = Platform.isIOS || Platform.isMacOS
-        ? DynamicLibrary.process()
-        : DynamicLibrary.open(getLibraryForPlatform());
+    var powersyncLib = _getDynamicLibraryForPlatform();
     sqlite.sqlite3.ensureExtensionLoaded(
         SqliteExtension.inLibrary(powersyncLib, 'sqlite3_powersync_init'));
   }
 
+  /// Returns the dynamic library for the current platform.
+  DynamicLibrary _getDynamicLibraryForPlatform() {
+    /// When running tests, we need to load the library for all platforms.
+    if (Platform.environment.containsKey('FLUTTER_TEST')) {
+      return DynamicLibrary.open(getLibraryForPlatform());
+    }
+    return (Platform.isIOS || Platform.isMacOS)
+        ? DynamicLibrary.process()
+        : DynamicLibrary.open(getLibraryForPlatform());
+  }
+
   void setupFunctions(sqlite.Database db) {
     db.createFunction(
       functionName: 'powersync_sleep',

packages/powersync/test/util.dart

@@ -35,6 +35,9 @@ class TestOpenFactory extends PowerSyncOpenFactory {
     sqlite_open.open.overrideFor(sqlite_open.OperatingSystem.linux, () {
       return DynamicLibrary.open('libsqlite3.so.0');
     });
+    sqlite_open.open.overrideFor(sqlite_open.OperatingSystem.macOS, () {
+      return DynamicLibrary.open('libsqlite3.dylib');
+    });
     return super.open(options);
   }