Let REGEXP support MySQL style word boundaries to fix #1384 (#2308)

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

Author: Copilot

src/55functions.js

@@ -192,7 +192,11 @@ stdlib.SUBSTRING =
 
 stdfn.REGEXP_LIKE = function (a, b, c) {
 	//	console.log(a,b,c);
-	return (a || '').search(RegExp(b, c)) > -1;
+	// Convert MySQL word boundaries to JavaScript word boundaries
+	// [[:<:]] -> \b (start of word)
+	// [[:>:]] -> \b (end of word)
+	var pattern = b.replace(/\[\[:<:\]\]/g, '\\b').replace(/\[\[:>:\]\]/g, '\\b');
+	return (a || '').search(RegExp(pattern, c)) > -1;
 };
 
 // Here we uses undefined instead of null

test/test1384.js

@@ -0,0 +1,103 @@
+if (typeof exports === 'object') {
+	var assert = require('assert');
+	var alasql = require('..');
+}
+
+describe('Test 1384 - REGEXP with MySQL word boundaries', function () {
+	const test = '1384';
+
+	before(function () {
+		alasql('create database test' + test);
+		alasql('use test' + test);
+	});
+
+	after(function () {
+		alasql('drop database test' + test);
+	});
+
+	it('A) Test REGEXP with [[:<:]] and [[:>:]] word boundaries', function () {
+		var sql =
+			'CREATE TABLE cities (city string, population number);' +
+			"INSERT INTO cities VALUES ('Rome,madrid',2863223),('Paris',2249975),('Berlin,rid',3517424), ('Madrid',3041579);" +
+			"SELECT * FROM cities WHERE city REGEXP '[[:<:]]rid[[:>:]]';";
+
+		var res = alasql(sql);
+		// When multiple statements are executed, result is an array with each statement's result
+		// [1, 4, [{matching_rows}]] where 1 = CREATE result, 4 = INSERT count, last = SELECT result
+		var selectResult = res[2];
+		assert.equal(selectResult.length, 1, 'Should match exactly one city');
+		assert.equal(selectResult[0].city, 'Berlin,rid', 'Should match Berlin,rid');
+		assert.equal(selectResult[0].population, 3517424, 'Should have correct population');
+	});
+
+	it('B) Test that REGEXP does not match partial words', function () {
+		alasql('CREATE TABLE test_words (word string)');
+		alasql(
+			"INSERT INTO test_words VALUES ('rid'),('Madrid'),('riddle'),('pride'),('ридда'),('Berlin,rid')"
+		);
+
+		// Should only match 'rid' and 'Berlin,rid' where 'rid' appears as a complete word
+		var res = alasql("SELECT * FROM test_words WHERE word REGEXP '[[:<:]]rid[[:>:]]'");
+		assert.equal(res.length, 2, 'Should match exactly two words');
+
+		var matched = res.map(r => r.word).sort();
+		assert.deepEqual(matched, ['Berlin,rid', 'rid'], 'Should match only complete word rid');
+	});
+
+	it('C) Test REGEXP_LIKE with word boundaries', function () {
+		assert.equal(
+			alasql("= REGEXP_LIKE('Berlin,rid', '[[:<:]]rid[[:>:]]')"),
+			true,
+			'Should match rid in Berlin,rid'
+		);
+		assert.equal(
+			alasql("= REGEXP_LIKE('Madrid', '[[:<:]]rid[[:>:]]')"),
+			false,
+			'Should not match rid in Madrid'
+		);
+		assert.equal(
+			alasql("= REGEXP_LIKE('riddle', '[[:<:]]rid[[:>:]]')"),
+			false,
+			'Should not match rid in riddle'
+		);
+		assert.equal(
+			alasql("= REGEXP_LIKE('rid', '[[:<:]]rid[[:>:]]')"),
+			true,
+			'Should match standalone rid'
+		);
+	});
+
+	it('D) Test mixed word boundaries', function () {
+		// Test start boundary only
+		assert.equal(
+			alasql("= REGEXP_LIKE('riddle', '[[:<:]]rid')"),
+			true,
+			'Should match rid at start of riddle'
+		);
+		assert.equal(
+			alasql("= REGEXP_LIKE('Madrid', '[[:<:]]rid')"),
+			false,
+			'Should not match rid in Madrid (not at word start)'
+		);
+
+		// Test end boundary only
+		assert.equal(
+			alasql("= REGEXP_LIKE('Madrid', 'rid[[:>:]]')"),
+			true,
+			'Should match rid at end of Madrid'
+		);
+		assert.equal(
+			alasql("= REGEXP_LIKE('riddle', 'rid[[:>:]]')"),
+			false,
+			'Should not match rid in riddle (not at word end)'
+		);
+	});
+
+	it('E) Test backward compatibility - normal REGEXP still works', function () {
+		// Ensure existing REGEXP functionality is not broken
+		assert.equal(alasql("= REGEXP_LIKE('abcdef', 'a.*')"), true);
+		assert.equal(alasql("= REGEXP_LIKE('abcdef', '[aq]')"), true);
+		assert.equal(alasql("= REGEXP_LIKE('abcdef', '[^qw]')"), true);
+		assert.equal(alasql("= REGEXP_LIKE('abcdef', '[qw]')"), false);
+	});
+});