Improve test coverage for SOURCE keyword to close #2218 (#2381)

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: mathiasrw <[email protected]>

Author: Copilot

test/test2218.js

@@ -0,0 +1,107 @@
+if (typeof exports === 'object') {
+	var assert = require('assert');
+	var alasql = require('..');
+}
+
+describe('Test 2218 - SOURCE keyword context', function () {
+	const testId = '2218';
+
+	before(function () {
+		alasql('create database test' + testId);
+		alasql('use test' + testId);
+	});
+
+	after(function () {
+		alasql('drop database test' + testId);
+	});
+
+	it('A) Should allow "source" as a table name', function () {
+		alasql('CREATE TABLE source(id INT, data VARCHAR(50))');
+		alasql('INSERT INTO source VALUES (1, "test1"), (2, "test2")');
+
+		var res = alasql('SELECT * FROM source ORDER BY id');
+		assert.deepEqual(res, [
+			{id: 1, data: 'test1'},
+			{id: 2, data: 'test2'},
+		]);
+	});
+
+	it('B) Should allow "source" as a column name', function () {
+		alasql('CREATE TABLE test_col(id INT, source VARCHAR(50))');
+		alasql('INSERT INTO test_col VALUES (1, "data1"), (2, "data2")');
+
+		var res = alasql('SELECT id, source FROM test_col ORDER BY id');
+		assert.deepEqual(res, [
+			{id: 1, source: 'data1'},
+			{id: 2, source: 'data2'},
+		]);
+	});
+
+	it('C) Should allow "source" as a JSON property name', function () {
+		alasql('CREATE TABLE test_json(data JSON)');
+		alasql('CREATE INDEX idx_source on test_json(data->source)');
+
+		alasql('INSERT INTO test_json VALUES (@{source:100})');
+		alasql('INSERT INTO test_json VALUES (@{source:200})');
+
+		var res = alasql('SELECT * FROM test_json ORDER BY data->source');
+		assert.equal(res.length, 2);
+		assert.deepEqual(res, [{data: {source: 100}}, {data: {source: 200}}]);
+	});
+
+	it('D) Should parse MERGE BY SOURCE syntax without error', function () {
+		// Test that MERGE statement with BY SOURCE clause is properly parsed
+		// The SOURCE keyword should be recognized in this context
+		// We just verify it parses - actual MERGE functionality is tested elsewhere
+		var sql = `
+			MERGE tbl_target AS t
+			USING tbl_source AS s
+			ON t.id = s.id
+			WHEN MATCHED THEN UPDATE SET t.name = s.name
+			WHEN NOT MATCHED BY SOURCE AND t.name LIKE 'S%' THEN DELETE
+			WHEN NOT MATCHED BY TARGET THEN INSERT VALUES (s.id, s.name)
+		`;
+
+		// This should not throw a parse error
+		var parsed = alasql.parse(sql);
+		assert.ok(parsed);
+		// The parsed object should have statements array
+		assert.ok(parsed.statements);
+		assert.ok(parsed.statements.length > 0);
+		// Check that it contains a MERGE statement with BY SOURCE clause
+		assert.ok(parsed.statements[0].using);
+	});
+
+	it('E) Should work with source in UNIQUE constraint', function () {
+		alasql('CREATE TABLE test_unique(id INT, source VARCHAR(50), UNIQUE(source))');
+
+		alasql('INSERT INTO test_unique VALUES (1, "unique1")');
+
+		// This should fail - duplicate source
+		assert.throws(() => {
+			alasql('INSERT INTO test_unique VALUES (2, "unique1")');
+		}, Error);
+
+		// This should succeed - different source
+		alasql('INSERT INTO test_unique VALUES (3, "unique2")');
+
+		var res = alasql('SELECT * FROM test_unique');
+		assert.equal(res.length, 2);
+	});
+
+	it('F) Should allow "source" in table alias', function () {
+		alasql('CREATE TABLE test_alias(id INT, data VARCHAR(50))');
+		alasql('INSERT INTO test_alias VALUES (1, "test1")');
+
+		var res = alasql('SELECT source.id, source.data FROM test_alias AS source');
+		assert.deepEqual(res, [{id: 1, data: 'test1'}]);
+	});
+
+	it('G) Should work with "source" in WHERE clause', function () {
+		alasql('CREATE TABLE test_where(id INT, source VARCHAR(50))');
+		alasql('INSERT INTO test_where VALUES (1, "value1"), (2, "value2")');
+
+		var res = alasql('SELECT * FROM test_where WHERE source = "value1"');
+		assert.deepEqual(res, [{id: 1, source: 'value1'}]);
+	});
+});