default to using package level Clock implementation

src/Adapters/InMemory/InMemoryClientAdapter.php

@@ -14,6 +14,7 @@
 use Cosmastech\StatsDClientAdapter\Adapters\InMemory\Models\InMemoryTimingRecord;
 use Cosmastech\StatsDClientAdapter\Adapters\StatsDClientAdapter;
 use Cosmastech\StatsDClientAdapter\TagNormalizers\NoopTagNormalizer;
+use Cosmastech\StatsDClientAdapter\Utility\Clock;
 use Psr\Clock\ClockInterface;
 
 class InMemoryClientAdapter implements StatsDClientAdapter, TagNormalizerAware
@@ -24,7 +25,7 @@ class InMemoryClientAdapter implements StatsDClientAdapter, TagNormalizerAware
     protected InMemoryStatsRecord $stats;
     protected readonly ClockInterface $clock;
 
-    public function __construct(ClockInterface $clock, array $defaultTags = [])
+    public function __construct(ClockInterface $clock = new Clock(), array $defaultTags = [])
     {
         $this->clock = $clock;
 

src/Utility/Clock.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace Cosmastech\StatsDClientAdapter\Utility;
+
+use DateTimeImmutable;
+use Psr\Clock\ClockInterface;
+
+/**
+ * The simplest possible interface: always return the current time.
+ */
+class Clock implements ClockInterface
+{
+    /**
+     * @inheritDoc
+     */
+    public function now(): DateTimeImmutable
+    {
+        return new DateTimeImmutable();
+    }
+}

tests/Adapters/InMemory/InMemoryTest.php

@@ -5,9 +5,7 @@
 use Cosmastech\StatsDClientAdapter\Adapters\InMemory\InMemoryClientAdapter;
 use Cosmastech\StatsDClientAdapter\Adapters\InMemory\Models\InMemoryStatsRecord;
 use Cosmastech\StatsDClientAdapter\Tests\BaseTestCase;
-use Cosmastech\StatsDClientAdapter\Tests\Doubles\ClockStub;
 use Cosmastech\StatsDClientAdapter\Tests\Doubles\TagNormalizerSpy;
-use DateTimeImmutable;
 use PHPUnit\Framework\Attributes\Test;
 
 class InMemoryTest extends BaseTestCase
@@ -16,7 +14,7 @@ class InMemoryTest extends BaseTestCase
     public function getStats_returnsInMemoryStatsRecord(): void
     {
         // Given
-        $inMemoryClient = new InMemoryClientAdapter(new ClockStub(new DateTimeImmutable()));
+        $inMemoryClient = new InMemoryClientAdapter();
 
         // When
         $record = $inMemoryClient->getStats();
@@ -30,7 +28,7 @@ public function getStats_returnsInMemoryStatsRecord(): void
     public function reset_clearsStats(): void
     {
         // Given
-        $inMemoryClient = new InMemoryClientAdapter(new ClockStub(new DateTimeImmutable()));
+        $inMemoryClient = new InMemoryClientAdapter();
 
         // And set some data
         $inMemoryClient->increment("bogus", 1, ["tag1" => true], 99);
@@ -49,7 +47,7 @@ public function reset_clearsStats(): void
     public function setTagNormalizer(): void
     {
         // Given
-        $inMemoryClient = new InMemoryClientAdapter(new ClockStub(new DateTimeImmutable()));
+        $inMemoryClient = new InMemoryClientAdapter();
 
         // And
         $tagNormalizerSpy = new TagNormalizerSpy();
@@ -66,7 +64,7 @@ public function setTagNormalizer(): void
     public function getClient_returnsNull(): void
     {
         // Given
-        $inMemoryClient = new InMemoryClientAdapter(new ClockStub(new DateTimeImmutable()));
+        $inMemoryClient = new InMemoryClientAdapter();
 
         // When
         $client = $inMemoryClient->getClient();

tests/Doubles/ClockStub.php

@@ -8,15 +8,17 @@
 
 class ClockStub implements ClockInterface
 {
+    /** @var array<int,DateTimeImmutable> */
     private readonly array $time;
+
     private int $currentIndex = 0;
 
     public function __construct(array|DateTimeImmutable $now)
     {
         $time = is_array($now) ? $now : [$now];
 
         if (empty($time)) {
-            throw new InvalidArgumentException("Clock requires at least one DateTimeImmutable");
+            throw new InvalidArgumentException("Clock requires at least one DateTimeImmutable.");
         }
 
         $this->time = $time;