All: Fixes #3234: Sync would fail in some cases due to a database error

CliClient/tests/database.js

@@ -0,0 +1,36 @@
+/* eslint-disable no-unused-vars */
+
+require('app-module-path').addPath(__dirname);
+
+const { time } = require('lib/time-utils.js');
+const { sortedIds, createNTestNotes, asyncTest, fileContentEqual, setupDatabase, setupDatabaseAndSynchronizer, db, synchronizer, fileApi, sleep, clearDatabase, switchClient, syncTargetId, objectsEqual, checkThrowAsync } = require('test-utils.js');
+const Folder = require('lib/models/Folder.js');
+const Note = require('lib/models/Note.js');
+const Setting = require('lib/models/Setting.js');
+const BaseModel = require('lib/BaseModel.js');
+const ArrayUtils = require('lib/ArrayUtils.js');
+const { shim } = require('lib/shim');
+
+process.on('unhandledRejection', (reason, p) => {
+	console.log('Unhandled Rejection at: Promise', p, 'reason:', reason);
+});
+
+describe('database', function() {
+	beforeEach(async (done) => {
+		await setupDatabaseAndSynchronizer(1);
+		await switchClient(1);
+		done();
+	});
+
+	it('should not modify cached field names', asyncTest(async () => {
+		const db = BaseModel.db();
+
+		const fieldNames = db.tableFieldNames('notes');
+		const fieldCount = fieldNames.length;
+		fieldNames.push('type_');
+
+		expect(fieldCount).toBeGreaterThan(0);
+		expect(db.tableFieldNames('notes').length).toBe(fieldCount);
+	}));
+
+});

ReactNativeClient/lib/joplin-database.js

@@ -146,7 +146,7 @@ class JoplinDatabase extends Database {
 		}
 		this.tableFieldNames_[tableName] = output;
 
-		return output;
+		return output.slice();
 	}
 
 	tableFields(tableName, options = null) {