Add startOfHour() and endOfHour() methods to ChronosTime

src/ChronosTime.php

@@ -325,6 +325,37 @@ public function setTime(int $hours = 0, int $minutes = 0, int $seconds = 0, int
         return $clone;
     }
 
+    /**
+     * Resets time to the start of the current hour.
+     *
+     * @return static
+     */
+    public function startOfHour(): static
+    {
+        $hourTicks = $this->ticks - $this->ticks % self::TICKS_PER_HOUR;
+
+        $clone = clone $this;
+        $clone->ticks = $hourTicks;
+
+        return $clone;
+    }
+
+    /**
+     * Sets time to the end of the current hour.
+     *
+     * @return static
+     */
+    public function endOfHour(): static
+    {
+        $hourTicks = $this->ticks - $this->ticks % self::TICKS_PER_HOUR;
+        $endTicks = $hourTicks + self::TICKS_PER_HOUR - 1;
+
+        $clone = clone $this;
+        $clone->ticks = $endTicks;
+
+        return $clone;
+    }
+
     /**
      * @param int $a Left side
      * @param int $a Right side

tests/TestCase/ChronosTimeTest.php

@@ -193,6 +193,36 @@ public function testSetTime(): void
         $this->assertSame('01:00:00.000001', $t->format('H:i:s.u'));
     }
 
+    public function testStartOfHour(): void
+    {
+        $t = ChronosTime::parse('12:30:45.123456');
+        $start = $t->startOfHour();
+
+        $this->assertNotSame($t, $start);
+        $this->assertSame('12:00:00.000000', $start->format('H:i:s.u'));
+
+        $t = ChronosTime::parse('00:59:59.999999');
+        $this->assertSame('00:00:00.000000', $t->startOfHour()->format('H:i:s.u'));
+
+        $t = ChronosTime::parse('23:01:01');
+        $this->assertSame('23:00:00.000000', $t->startOfHour()->format('H:i:s.u'));
+    }
+
+    public function testEndOfHour(): void
+    {
+        $t = ChronosTime::parse('12:30:45.123456');
+        $end = $t->endOfHour();
+
+        $this->assertNotSame($t, $end);
+        $this->assertSame('12:59:59.999999', $end->format('H:i:s.u'));
+
+        $t = ChronosTime::parse('00:00:00');
+        $this->assertSame('00:59:59.999999', $t->endOfHour()->format('H:i:s.u'));
+
+        $t = ChronosTime::parse('23:30:00');
+        $this->assertSame('23:59:59.999999', $t->endOfHour()->format('H:i:s.u'));
+    }
+
     public function testFormat(): void
     {
         $t = new ChronosTime('23:59:59.999999');