[RateLimit] Allow to get RateLimit without consuming again

Author: ERuban

src/Symfony/Component/RateLimiter/Policy/SlidingWindowLimiter.php

@@ -65,12 +65,18 @@ public function reserve(int $tokens = 1, float $maxTime = null): Reservation
             $now = microtime(true);
             $hitCount = $window->getHitCount();
             $availableTokens = $this->getAvailableTokens($hitCount);
+            if (0 === $tokens) {
+                $resetDuration = $window->calculateTimeForTokens($this->limit, $window->getHitCount());
+                $resetTime = \DateTimeImmutable::createFromFormat('U', $availableTokens ? floor($now) : floor($now + $resetDuration));
+
+                return new Reservation($now, new RateLimit($availableTokens, $resetTime, true, $this->limit));
+            }
             if ($availableTokens >= $tokens) {
                 $window->add($tokens);
 
                 $reservation = new Reservation($now, new RateLimit($this->getAvailableTokens($window->getHitCount()), \DateTimeImmutable::createFromFormat('U', floor($now)), true, $this->limit));
             } else {
-                $waitDuration = $window->calculateTimeForTokens($this->limit, max(1, $tokens));
+                $waitDuration = $window->calculateTimeForTokens($this->limit, $tokens);
 
                 if (null !== $maxTime && $waitDuration > $maxTime) {
                     // process needs to wait longer than set interval

src/Symfony/Component/RateLimiter/Tests/Policy/SlidingWindowLimiterTest.php

@@ -52,6 +52,7 @@ public function testConsume()
         $rateLimit = $limiter->consume(10);
         $this->assertTrue($rateLimit->isAccepted());
         $this->assertSame(10, $rateLimit->getLimit());
+        $this->assertSame(0, $rateLimit->getRemainingTokens());
     }
 
     public function testWaitIntervalOnConsumeOverLimit()
@@ -76,6 +77,9 @@ public function testReserve()
 
         // 2 over the limit, causing the WaitDuration to become 2/10th of the 12s interval
         $this->assertEqualsWithDelta(12 / 5, $limiter->reserve(4)->getWaitDuration(), 1);
+
+        $limiter->reset();
+        $this->assertEquals(0, $limiter->reserve(10)->getWaitDuration());
     }
 
     public function testPeekConsume()
@@ -90,7 +94,7 @@ public function testPeekConsume()
             $this->assertTrue($rateLimit->isAccepted());
             $this->assertSame(10, $rateLimit->getLimit());
             $this->assertEquals(
-                \DateTimeImmutable::createFromFormat('U.u', sprintf('%.6F', microtime(true))),
+                \DateTimeImmutable::createFromFormat('U', (string) floor(microtime(true))),
                 $rateLimit->getRetryAfter()
             );
         }
@@ -101,7 +105,7 @@ public function testPeekConsume()
         $this->assertEquals(0, $rateLimit->getRemainingTokens());
         $this->assertTrue($rateLimit->isAccepted());
         $this->assertEquals(
-            \DateTimeImmutable::createFromFormat('U.u', sprintf('%.6F', microtime(true) + 12)),
+            \DateTimeImmutable::createFromFormat('U', (string) floor(microtime(true) + 12)),
             $rateLimit->getRetryAfter()
         );
     }