Merge pull request #29 from assoconnect/fix_timetraveler

Fix traveler for last day of month

Author: sylfabre

src/TimeTraveler.php

@@ -14,6 +14,9 @@ class TimeTraveler
      *
      * (new AbsoluteDate(2020-01-31))->modify('+1 month') = 2020-02-31 => 2020-03-02 so more than a month
      * addMonth(new AbsoluteDate(2020-01-31)) = 2020-02-29
+     *
+     * (new AbsoluteDate(2020-06-30))->modify('+1 month') = 2020-07-30 so less than a month
+     * addMonth(new AbsoluteDate(2020-06-30)) = 2020-07-31
      */
     public function addMonth(AbsoluteDate $from): AbsoluteDate
     {
@@ -22,7 +25,8 @@ public function addMonth(AbsoluteDate $from): AbsoluteDate
         while ($expectedMonth !== intval($next->format('n'))) {
             $next = $next->modify('-1 day');
         }
-        return $next;
+
+        return $this->modifyForTheLastDayOfThisMonthIfNeedBe($next, $from);
     }
 
     /**
@@ -51,7 +55,10 @@ public function addMonthWithReference(AbsoluteDate $reference, AbsoluteDate $fro
             intval($next->modify('last day of this month')->format('j'))
         );
         $dayString = str_pad(strval($day), 2, '0', STR_PAD_LEFT);
-        return new AbsoluteDate($next->format('Y-m') . '-' . $dayString);
+        return $this->modifyForTheLastDayOfThisMonthIfNeedBe(
+            new AbsoluteDate($next->format('Y-m') . '-' . $dayString),
+            $reference
+        );
     }
 
     /**
@@ -68,4 +75,13 @@ public function addYear(AbsoluteDate $from): AbsoluteDate
         }
         return $next;
     }
+
+    private function modifyForTheLastDayOfThisMonthIfNeedBe(AbsoluteDate $result, AbsoluteDate $reference): AbsoluteDate
+    {
+        $pattern = 'last day of this month';
+        if ($reference->equalsTo($reference->modify($pattern))) {
+            return $result->modify($pattern);
+        }
+        return $result;
+    }
 }

tests/TimeTravelerTest.php

@@ -31,7 +31,8 @@ public function provideMonths(): iterable
         yield ['2020-01-29', '2020-02-29'];
         yield ['2020-01-30', '2020-02-29'];
         yield ['2020-01-31', '2020-02-29'];
-        yield ['2020-02-29', '2020-03-29'];
+        yield ['2020-02-29', '2020-03-31'];
+        yield ['2020-06-30', '2020-07-31'];
     }
 
     /** @dataProvider provideMonthsWithReference */
@@ -55,6 +56,9 @@ public function provideMonthsWithReference(): iterable
         yield ['2020-01-30', '2020-02-29', '2020-03-30'];
         yield ['2020-01-31', '2020-02-29', '2020-03-31'];
         yield ['2020-01-31', '2020-03-31', '2020-04-30'];
+        yield ['2020-06-30', '2020-06-30', '2020-07-31'];
+        yield ['2020-06-30', '2020-07-31', '2020-08-31'];
+        yield ['2020-06-30', '2020-08-31', '2020-09-30'];
     }
 
     /** @dataProvider provideMonthsWithReferenceOverYear */
@@ -78,6 +82,7 @@ public function provideMonthsWithReferenceOverYear(): iterable
         yield ['2020-01-29', '2021-01-29'];
         yield ['2020-01-30', '2021-01-30'];
         yield ['2020-01-31', '2021-01-31'];
+        yield ['2020-06-30', '2021-06-30'];
     }
 
     /** @dataProvider provideYears */
@@ -92,5 +97,6 @@ public function provideYears(): iterable
         yield ['2020-01-01', '2021-01-01'];
         yield ['2020-01-31', '2021-01-31'];
         yield ['2020-02-29', '2021-02-28'];
+        yield ['2020-06-30', '2021-06-30'];
     }
 }