Add a library for running SQLite databases in threads (#7350)

test/lib/sql.js

@@ -0,0 +1,30 @@
+"use strict";
+const {SQL} = require('../../lib/sql');
+const assert = require('../assert').strict;
+
+const database = SQL(`:memory:`);
+
+describe(`SQLite worker wrapper`, async () => {
+	// prepare statements and set up table
+	await database.exec(`CREATE TABLE IF NOT EXISTS test (col TEXT, col2 TEXT)`);
+	const select = await database.prepare(`SELECT * FROM test`); // 0
+	const insert = await database.prepare(`INSERT INTO test (col, col2) VALUES (?, ?)`); // 1
+	it(`should require you to prepare a statement before running`, async () => {
+		assert.throws(async () => {
+			await database.get('SELECT col FROM test');
+		}, /Prepare a statement before using another database function with SQLDatabase.prepare/);
+	});
+	it(`should retrieve one line from Database.get`, async () => {
+		const result = await database.get(select);
+		assert(result.length, 1);
+	});
+	it(`should support both statement strings and corresponding numbers`, async () => {
+		await database.run(`INSERT INTO test (col, col2) VALUES(?, ?)`, ['a', 'b']);
+		await database.run(insert, ['a', 'b']);
+	});
+	it(`should support both inline and object params`, async () => {
+		const num = await database.prepare(`INSERT INTO test (col, col2) VALUES($col, $col2)`);
+		await database.run(insert, ['a', 'b']);
+		await database.run(num, {col: 'a', col1: 'b'});
+	});
+});