Use Month enum internally where appropriate.

src/Field/WeekOfYear.php

@@ -7,6 +7,7 @@
 use Brick\DateTime\DateTimeException;
 use Brick\DateTime\DayOfWeek;
 use Brick\DateTime\LocalDate;
+use Brick\DateTime\Month;
 
 /**
  * The week-of-year field.
@@ -51,7 +52,7 @@ public static function check(int $weekOfYear, ?int $year = null): void
      */
     public static function is53WeekYear(int $year): bool
     {
-        $date = LocalDate::of($year, 1, 1);
+        $date = LocalDate::of($year, Month::JANUARY, 1);
         $dayOfWeek = $date->getDayOfWeek();
 
         return $dayOfWeek === DayOfWeek::THURSDAY

src/LocalDate.php

@@ -111,7 +111,7 @@ public static function ofYearDay(int $year, int $dayOfYear): LocalDate
 
         $dayOfMonth = $dayOfYear - $monthOfYear->getFirstDayOfYear($isLeap) + 1;
 
-        return LocalDate::of($year, $monthOfYear->value, $dayOfMonth);
+        return LocalDate::of($year, $monthOfYear, $dayOfMonth);
     }
 
     /**
@@ -223,7 +223,7 @@ public static function min(): LocalDate
             return $min;
         }
 
-        return $min = LocalDate::of(self::MIN_YEAR, 1, 1);
+        return $min = LocalDate::of(self::MIN_YEAR, Month::JANUARY, 1);
     }
 
     /**
@@ -240,7 +240,7 @@ public static function max(): LocalDate
             return $max;
         }
 
-        return $max = LocalDate::of(self::MAX_YEAR, 12, 31);
+        return $max = LocalDate::of(self::MAX_YEAR, Month::DECEMBER, 31);
     }
 
     /**

src/LocalTime.php

@@ -607,7 +607,7 @@ public function toSecondOfDay(): int
      */
     public function toNativeDateTime(): DateTime
     {
-        return $this->atDate(LocalDate::of(0, 1, 1))->toNativeDateTime();
+        return $this->atDate(LocalDate::of(0, Month::JANUARY, 1))->toNativeDateTime();
     }
 
     /**

src/Year.php

@@ -274,8 +274,8 @@ public function atMonthDay(MonthDay $monthDay): LocalDate
     public function toLocalDateRange(): LocalDateRange
     {
         return LocalDateRange::of(
-            $this->atMonth(1)->getFirstDay(),
-            $this->atMonth(12)->getLastDay(),
+            $this->atMonth(Month::JANUARY)->getFirstDay(),
+            $this->atMonth(Month::DECEMBER)->getLastDay(),
         );
     }
 

src/YearWeek.php

@@ -206,7 +206,7 @@ public function atDay(DayOfWeek|int $dayOfWeek): LocalDate
             $dayOfWeek = DayOfWeek::from($dayOfWeek);
         }
 
-        $correction = LocalDate::of($this->year, 1, 4)->getDayOfWeek()->value + 3;
+        $correction = LocalDate::of($this->year, Month::JANUARY, 4)->getDayOfWeek()->value + 3;
         $dayOfYear = $this->week * 7 + $dayOfWeek->value - $correction;
         $maxDaysOfYear = Field\Year::isLeap($this->year) ? 366 : 365;