Upsert test.

test/upsert.test.js

+var sqlite3 = require('..');
+var assert = require('assert');
+
+describe('query properties', function() {
+    var db;
+    before(function(done) {
+        db = new sqlite3.Database(':memory:');
+        db.run("CREATE TABLE foo (id INT PRIMARY KEY, count INT)", done);
+    });
+
+    it('should upsert', function(done) {
+        var stmt = db.prepare("INSERT INTO foo VALUES(?, ?)");
+        stmt.run(1, 1, function(err) { // insert 1
+            if (err) throw err;
+            var upsert_stmt = db.prepare("INSERT INTO foo VALUES(?, ?) ON CONFLICT (id) DO UPDATE SET count = count + excluded.count");
+            upsert_stmt.run(1, 2, function(err) { // add 2
+                if (err) throw err;
+                var select_stmt = db.prepare("SELECT count FROM foo WHERE id = ?");
+                select_stmt.get(1, function(err, row) {
+                    if (err) throw err;
+                    assert.equal(row.count, 3); // equals 3
+                });
+            })
+        });
+        db.wait(done);
+    });
+});