Merge pull request #656 from kroky/bugfix/bymonth-rrule

Yearly rrule compliance by the iterator

Author: phil-davis

lib/Recur/RRuleIterator.php

@@ -610,7 +610,11 @@ protected function nextYearly(): void
                     // If we advanced to the next month or year, the first
                     // occurrence is always correct.
                     if ($occurrence > $currentDayOfMonth || $advancedToNewMonth) {
-                        break 2;
+                        // only consider byMonth matches,
+                        // otherwise, we don't follow RRule correctly
+                        if (in_array($currentMonth, $this->byMonth)) {
+                            break 2;
+                        }
                     }
                 }
 

tests/VObject/Recur/RRuleIteratorTest.php

@@ -922,6 +922,52 @@ public function testYearlyBySetPosLoop(): void
         );
     }
 
+    /**
+     * This caused an incorrect date to be returned by the rule iterator when
+     * start date was not on the rrule list.
+     *
+     * @dataProvider yearlyStartDateNotOnRRuleListProvider
+     */
+    public function testYearlyStartDateNotOnRRuleList(string $rule, string $start, array $expected): void
+    {
+        $this->parse($rule, $start, $expected);
+    }
+
+    public function yearlyStartDateNotOnRRuleListProvider(): array
+    {
+        return [
+            [
+                'FREQ=YEARLY;BYMONTH=6;BYDAY=-1FR;UNTIL=20250901T000000Z',
+                '2023-09-01 12:00:00',
+                [
+                    '2023-09-01 12:00:00',
+                    '2024-06-28 12:00:00',
+                    '2025-06-27 12:00:00',
+                ],
+            ],
+            [
+                'FREQ=YEARLY;BYMONTH=6;BYDAY=-1FR;UNTIL=20250901T000000Z',
+                '2023-06-01 12:00:00',
+                [
+                    '2023-06-01 12:00:00',
+                    '2023-06-30 12:00:00',
+                    '2024-06-28 12:00:00',
+                    '2025-06-27 12:00:00',
+                ],
+            ],
+            [
+                'FREQ=YEARLY;BYMONTH=6;BYDAY=-1FR;UNTIL=20250901T000000Z',
+                '2023-05-01 12:00:00',
+                [
+                    '2023-05-01 12:00:00',
+                    '2023-06-30 12:00:00',
+                    '2024-06-28 12:00:00',
+                    '2025-06-27 12:00:00',
+                ],
+            ],
+        ];
+    }
+
     /**
      * Something, somewhere produced an ics with an interval set to 0. Because
      * this means we increase the current day (or week, month) by 0, this also