test(functions): add math, aggregate and stats tests

2026-08-28 11:17:00 +02:00
1 parent e0d5adb91c
commit c31cea00f7
@@ -0,0 +1,78 @@
+import 'package:cellar/cellar.dart';
+import 'package:test/test.dart';
+
+double num(CellValue value) => (value as NumberValue).value;
+
+Sheet withColumn(List<String> values) {
+  final sheet = Sheet();
+  for (var i = 0; i < values.length; i++) {
+    sheet.setValue('A${i + 1}', values[i]);
+  }
+  return sheet;
+}
+
+void main() {
+  group('statistics functions', () {
+    test('MEDIAN', () {
+      final odd = withColumn(['3', '1', '2']);
+      odd.setValue('B1', '=MEDIAN(A1:A3)');
+      expect(num(odd.valueOf('B1')), 2);
+      final even = withColumn(['1', '2', '3', '4']);
+      even.setValue('B1', '=MEDIAN(A1:A4)');
+      expect(num(even.valueOf('B1')), 2.5);
+    });
+
+    test('MODE finds the most frequent value', () {
+      final sheet = withColumn(['2', '4', '4', '7', '4', '2']);
+      sheet.setValue('B1', '=MODE(A1:A6)');
+      expect(num(sheet.valueOf('B1')), 4);
+    });
+
+    test('COUNT COUNTA COUNTBLANK', () {
+      final sheet = Sheet();
+      sheet.setValue('A1', '10');
+      sheet.setValue('A2', 'text');
+      sheet.setValue('A4', '5');
+      sheet.setValue('C1', '=COUNT(A1:A4)');
+      sheet.setValue('C2', '=COUNTA(A1:A4)');
+      sheet.setValue('C3', '=COUNTBLANK(A1:A4)');
+      expect(num(sheet.valueOf('C1')), 2);
+      expect(num(sheet.valueOf('C2')), 3);
+      expect(num(sheet.valueOf('C3')), 1);
+    });
+
+    test('variance and standard deviation', () {
+      final sheet = withColumn(['2', '4', '4', '4', '5', '5', '7', '9']);
+      sheet.setValue('B1', '=VARP(A1:A8)');
+      sheet.setValue('B2', '=STDEVP(A1:A8)');
+      sheet.setValue('B3', '=VAR(A1:A8)');
+      expect(num(sheet.valueOf('B1')), closeTo(4, 1e-9));
+      expect(num(sheet.valueOf('B2')), closeTo(2, 1e-9));
+      expect(num(sheet.valueOf('B3')), closeTo(4.5714286, 1e-6));
+    });
+
+    test('LARGE SMALL RANK', () {
+      final sheet = withColumn(['5', '1', '9', '3']);
+      sheet.setValue('B1', '=LARGE(A1:A4, 1)');
+      sheet.setValue('B2', '=SMALL(A1:A4, 2)');
+      sheet.setValue('B3', '=RANK(9, A1:A4)');
+      sheet.setValue('B4', '=RANK(1, A1:A4, 1)');
+      expect(num(sheet.valueOf('B1')), 9);
+      expect(num(sheet.valueOf('B2')), 3);
+      expect(num(sheet.valueOf('B3')), 1);
+      expect(num(sheet.valueOf('B4')), 1);
+    });
+
+    test('PERCENTILE interpolates', () {
+      final sheet = withColumn(['1', '2', '3', '4']);
+      sheet.setValue('B1', '=PERCENTILE(A1:A4, 0.5)');
+      expect(num(sheet.valueOf('B1')), 2.5);
+    });
+
+    test('AVERAGE of an empty selection is #DIV/0!', () {
+      final sheet = Sheet();
+      sheet.setValue('B1', '=AVERAGE(A1:A3)');
+      expect(sheet.valueOf('B1'), const ErrorValue(ErrorKind.divZero));
+    });
+  });
+}