Support BETWEEN operator in CASE statement to fix #735 (#2195)

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/50expression.js

@@ -249,6 +249,15 @@
 			if (this.left && this.left.findAggregator) {
 				this.left.findAggregator(query);
 			}
+			// Handle BETWEEN operators which have right1 and right2
+			if (this.op === 'BETWEEN' || this.op === 'NOT BETWEEN') {
+				if (this.right1 && this.right1.findAggregator) {
+					this.right1.findAggregator(query);
+				}
+				if (this.right2 && this.right2.findAggregator) {
+					this.right2.findAggregator(query);
+				}
+			}
 			// Do not go in > ALL
 			if (this.right && this.right.findAggregator && !this.allsome) {
 				this.right.findAggregator(query);

test/test735.js

@@ -0,0 +1,66 @@
+if (typeof exports === 'object') {
+	var assert = require('assert');
+	var alasql = require('..');
+}
+
+describe('Test 735: BETWEEN in CASE statement', function () {
+	it('1. CASE WHEN with > and < operators should work', function (done) {
+		var cities = [
+			{City: 'Moscow', Population: 1},
+			{City: 'London', Population: 10},
+			{City: 'Paris', Population: 100},
+		];
+
+		var res = alasql(
+			'SELECT City, CASE WHEN Population > 1 AND Population < 100 THEN "yes" ELSE "no" END AS isBetween1and100 FROM ?',
+			[cities]
+		);
+
+		assert.deepEqual(res, [
+			{City: 'Moscow', isBetween1and100: 'no'},
+			{City: 'London', isBetween1and100: 'yes'},
+			{City: 'Paris', isBetween1and100: 'no'},
+		]);
+		done();
+	});
+
+	it('2. CASE WHEN with BETWEEN operator should work', function (done) {
+		var cities = [
+			{City: 'Moscow', Population: 1},
+			{City: 'London', Population: 10},
+			{City: 'Paris', Population: 100},
+		];
+
+		var res = alasql(
+			'SELECT City, CASE WHEN Population BETWEEN 1 AND 100 THEN "yes" ELSE "no" END AS isBetween1and100 FROM ?',
+			[cities]
+		);
+
+		assert.deepEqual(res, [
+			{City: 'Moscow', isBetween1and100: 'yes'},
+			{City: 'London', isBetween1and100: 'yes'},
+			{City: 'Paris', isBetween1and100: 'yes'},
+		]);
+		done();
+	});
+
+	it('3. CASE WHEN with BETWEEN operator (exclusive) should work', function (done) {
+		var cities = [
+			{City: 'Moscow', Population: 1},
+			{City: 'London', Population: 10},
+			{City: 'Paris', Population: 100},
+		];
+
+		var res = alasql(
+			'SELECT City, CASE WHEN Population BETWEEN 2 AND 99 THEN "yes" ELSE "no" END AS isBetween2and99 FROM ?',
+			[cities]
+		);
+
+		assert.deepEqual(res, [
+			{City: 'Moscow', isBetween2and99: 'no'},
+			{City: 'London', isBetween2and99: 'yes'},
+			{City: 'Paris', isBetween2and99: 'no'},
+		]);
+		done();
+	});
+});