fix: Session::__get() should trigger error when data does not exist

Author: Jonathon Hill

behat.yml

@@ -1,5 +1,10 @@
 default:
   suites:
+    access:
+      paths:
+        - 'features/access.feature'
+      contexts:
+        - 'Compwright\PhpSession\BehaviorTest\AccessContext'
     concurrency:
       paths:
         - 'features/concurrency.feature'

features/access.feature

@@ -0,0 +1,20 @@
+Feature: Session access
+  Scenario: Check data does not exist
+    When data does not exist
+    Then property check returns false
+  Scenario: Check data exist
+    When data exists
+    Then property check returns true
+  Scenario: Read data that exists
+    When data exists
+    Then property read returns data
+  Scenario: Read data that does not exist
+    When data does not exist
+    Then property read triggers error
+    And property read returns null
+  Scenario: Null coalesce when data does not exist
+    When data does not exist
+    Then property read with null coalesce returns null
+  Scenario: Write data
+    When data does not exist
+    Then property write succeeds

src/Session.php

@@ -50,7 +50,8 @@ public function __get(string $name)
             throw new RuntimeException('Session not initialized');
         }
 
-        return $this->contents[$name] ?? null;
+        // @phpstan-ignore-next-line
+        return $this->contents[$name];
     }
 
     public function __isset(string $name): bool

tests/behavior/AccessContext.php

@@ -0,0 +1,104 @@
+<?php
+
+namespace Compwright\PhpSession\BehaviorTest;
+
+use Behat\Behat\Context\Context;
+use Compwright\PhpSession\Session;
+use PHPUnit\Framework\Assert;
+use Throwable;
+
+/**
+ * Defines application features from the specific context.
+ */
+class AccessContext implements Context
+{
+    private Session $session;
+
+    /**
+     * @When data does not exist
+     */
+    public function dataDoesNotExist(): void
+    {
+        $this->session = new Session('foo', 'bar', []);
+        Assert::assertTrue($this->session->isWriteable());
+        Assert::assertCount(0, $this->session);
+    }
+
+    /**
+     * @When data exists
+     */
+    public function dataExists(): void
+    {
+        $this->session = new Session('foo', 'bar', ['foo' => 'bar']);
+        Assert::assertTrue($this->session->isWriteable());
+        Assert::assertCount(1, $this->session);
+    }
+
+    /**
+     * @Then property check returns false
+     */
+    public function propertyCheckReturnsFalse(): void
+    {
+        Assert::assertFalse(isset($this->session->foo));
+    }
+
+    /**
+     * @Then property check returns true
+     */
+    public function propertyCheckReturnsTrue(): void
+    {
+        Assert::assertTrue(isset($this->session->foo));
+    }
+
+    /**
+     * @Then property read returns data
+     */
+    public function propertyReadReturnsData(): void
+    {
+        Assert::assertEquals('bar', $this->session->foo);
+    }
+
+    /**
+     * @Then property read triggers error
+     */
+    public function propertyReadTriggersNoticeError(): void
+    {
+        try {
+            $errorThrown = false;
+            $bar = $this->session->bar;
+            // @phpstan-ignore-next-line
+        } catch (Throwable $e) {
+            $errorThrown = true;
+        } finally {
+            Assert::assertTrue($errorThrown);
+        }
+    }
+
+    /**
+     * @Then property read returns null
+     */
+    public function propertyReadReturnsNull(): void
+    {
+        $bar = @$this->session->bar;
+        Assert::assertSame(null, $bar);
+    }
+
+    /**
+     * @Then property read with null coalesce returns null
+     */
+    public function propertyReadWithNullCoalesceReturnsNull(): void
+    {
+        $bar = $this->session->bar ?? null;
+        Assert::assertSame(null, $bar);
+    }
+
+    /**
+     * @Then property write succeeds
+     */
+    public function propertyWriteSucceeds(): void
+    {
+        $this->session->bar = 'baz';
+        Assert::assertCount(1, $this->session);
+        Assert::assertTrue(isset($this->session->bar));
+    }
+}