added checkpoint tests

Author: JoshuaWise

test/40.database.checkpoint.js

@@ -1,6 +1,39 @@
 var expect = require('chai').expect;
+var fs = require('fs');
 var Database = require('../.');
+var db;
+
+before(function (done) {
+	db = new Database('temp/' + require('path').basename(__filename).split('.')[0] + '.db');
+	db.on('open', function () {
+		db.pragma('journal_mode = WAL');
+		db.prepare('CREATE TABLE entries (a TEXT, b INTEGER)').run();
+		done();
+	});
+});
 
 describe('Database#checkpoint()', function () {
-	
+	describe('before a checkpoint', function () {
+		it('every insert should increase the size of the WAL file', function () {
+			var size1, size2;
+			for (var i=0; i<10; ++i) {
+				size1 = fs.statSync(db.name + '-wal').size;
+				db.prepare('INSERT INTO entries VALUES (?, ?)').run('bar', 999);
+				size2 = fs.statSync(db.name + '-wal').size;
+				expect(size2).to.be.above(size1);
+			}
+		});
+	});
+	describe('after a checkpoint', function () {
+		it('inserts should NOT increase the size of the WAL file', function () {
+			expect(db.checkpoint()).to.equal(1);
+			var size1, size2;
+			for (var i=0; i<10; ++i) {
+				size1 = fs.statSync(db.name + '-wal').size;
+				db.prepare('INSERT INTO entries VALUES (?, ?)').run('bar', 999);
+				size2 = fs.statSync(db.name + '-wal').size;
+				expect(size2).to.be.equal(size1);
+			}
+		});
+	});
 });