feat: make Session iterable

features/access.feature

@@ -27,3 +27,9 @@ Feature: Session access
   Scenario: Write array access data
     When data does not exist
     Then array access write succeeds
+  Scenario: Iterate over populated session
+    When data exists
+    Then data is iterated
+  Scenario: Iterate over non-populated session
+    When data does not exist
+    Then data is not iterated

src/Session.php

@@ -4,11 +4,12 @@
 
 namespace Compwright\PhpSession;
 
+use Iterator;
 use Countable;
 use ArrayAccess;
 use RuntimeException;
 
-class Session implements ArrayAccess, Countable
+class Session implements ArrayAccess, Iterator, Countable
 {
     protected string $name;
 
@@ -223,6 +224,56 @@ public function toArray(): array
         return $this->contents ?? [];
     }
 
+    public function rewind(): void
+    {
+        if (!$this->isInitialized()) {
+            throw new RuntimeException('Session not initialized');
+        }
+
+        // @phpstan-ignore-next-line
+        reset($this->contents);
+    }
+
+    public function current(): mixed
+    {
+        if (!$this->isInitialized()) {
+            throw new RuntimeException('Session not initialized');
+        }
+
+        // @phpstan-ignore-next-line
+        return current($this->contents);
+    }
+
+    public function key(): mixed
+    {
+        if (!$this->isInitialized()) {
+            throw new RuntimeException('Session not initialized');
+        }
+
+        // @phpstan-ignore-next-line
+        return key($this->contents);
+    }
+
+    public function next(): void
+    {
+        if (!$this->isInitialized()) {
+            throw new RuntimeException('Session not initialized');
+        }
+
+        // @phpstan-ignore-next-line
+        next($this->contents);
+    }
+
+    public function valid(): bool
+    {
+        if (!$this->isInitialized()) {
+            throw new RuntimeException('Session not initialized');
+        }
+
+        // @phpstan-ignore-next-line
+        return key($this->contents) !== null;
+    }
+
     public function count(): int
     {
         return count($this->contents ?? []);

tests/behavior/AccessContext.php

@@ -169,4 +169,34 @@ public function arrayAccessWriteSucceeds(): void
         Assert::assertCount(1, $this->session);
         Assert::assertTrue(isset($this->session['bar']));
     }
+
+    /**
+     * @Then data is iterated
+     */
+    public function iteratorSucceeds(): void
+    {
+        $counter = 0;
+
+        foreach ($this->session as $var => $val) {
+            Assert::assertSame('foo', $var);
+            Assert::assertSame('bar', $val);
+            $counter++;
+        }
+
+        Assert::assertSame(1, $counter);
+    }
+
+    /**
+     * @Then data is not iterated
+     */
+    public function iteratorFails(): void
+    {
+        $counter = 0;
+
+        foreach ($this->session as $var => $val) {
+            $counter++;
+        }
+
+        Assert::assertSame(0, $counter);
+    }
 }