Added FileConnector and accompany test.

composer.json

@@ -17,7 +17,7 @@
   },
   "autoload": {
     "psr-4": {
-      "ScriptFUSION\\Porter\\Net\\File\\": "src"
+      "ScriptFUSION\\Porter\\Connector\\File\\": "src"
     }
   },
   "autoload-dev": {

src/FileConnector.php

@@ -0,0 +1,22 @@
+<?php
+declare(strict_types=1);
+
+namespace ScriptFUSION\Porter\Connector\File;
+
+use ScriptFUSION\Porter\Connector\ConnectionContext;
+use ScriptFUSION\Porter\Connector\Connector;
+use ScriptFUSION\Porter\Options\EncapsulatedOptions;
+
+class FileConnector implements Connector
+{
+    public function fetch(ConnectionContext $context, $source, EncapsulatedOptions $options = null)
+    {
+        if (preg_match('[^(\w+)://]', $source, $matches) && strtolower($matches[1]) !== 'file') {
+            throw new InvalidFilePathException($source);
+        }
+
+        return $context->retry(function () use ($source) {
+            return file_get_contents($source);
+        });
+    }
+}

src/InvalidFilePathException.php

@@ -0,0 +1,12 @@
+<?php
+declare(strict_types=1);
+
+namespace ScriptFUSION\Porter\Connector\File;
+
+final class InvalidFilePathException extends \RuntimeException
+{
+    public function __construct(string $path)
+    {
+        parent::__construct("The specified file path was invalid: \"$path\".");
+    }
+}

test/FixtureFactory.php

@@ -0,0 +1,23 @@
+<?php
+declare(strict_types=1);
+
+namespace ScriptFUSIONTest;
+
+use ScriptFUSION\Porter\Connector\ConnectionContext;
+use ScriptFUSION\StaticClass;
+
+final class FixtureFactory
+{
+    use StaticClass;
+
+    public static function createConnectionContext(): ConnectionContext
+    {
+        return new ConnectionContext(
+            false,
+            function () {
+                // Intentionally empty.
+            },
+            1
+        );
+    }
+}

test/Functional/FileConnectorTest.php

@@ -0,0 +1,78 @@
+<?php
+declare(strict_types=1);
+
+namespace ScriptFUSIONTest\Functional;
+
+use PHPUnit\Framework\TestCase;
+use ScriptFUSION\Porter\Connector\File\FileConnector;
+use ScriptFUSION\Porter\Connector\File\InvalidFilePathException;
+use ScriptFUSION\Retry\FailingTooHardException;
+use ScriptFUSIONTest\FixtureFactory;
+
+/**
+ * @see FileConnector
+ */
+final class FileConnectorTest extends TestCase
+{
+    /**
+     * @var FileConnector
+     */
+    private $connector;
+
+    protected function setUp()
+    {
+        $this->connector = new FileConnector;
+    }
+
+    /**
+     * Tests that an empty path fails.
+     */
+    public function testEmpty()
+    {
+        $this->expectException(FailingTooHardException::class);
+
+        $this->fetch('');
+    }
+
+    /**
+     * Tests that absolute paths succeed.
+     */
+    public function testAbsolutePath()
+    {
+        self::assertStringEqualsFile(__FILE__, $this->fetch(__FILE__));
+    }
+
+    /**
+     * Tests that relative paths succeed.
+     */
+    public function testRelativePath()
+    {
+        chdir(__DIR__);
+
+        self::assertStringEqualsFile(__FILE__, $this->fetch(basename(__FILE__)));
+    }
+
+    /**
+     * Tests that accessing the file:// protocol, with any capitalization, succeeds.
+     */
+    public function testFileProtocol()
+    {
+        self::assertStringEqualsFile(__FILE__, $this->fetch('file://' . __FILE__));
+        self::assertStringEqualsFile(__FILE__, $this->fetch('FILE://' . __FILE__));
+    }
+
+    /**
+     * Tests that accessing any protocol other than file:// throws an exception.
+     */
+    public function testHttpProtocol()
+    {
+        $this->expectException(InvalidFilePathException::class);
+
+        $this->fetch('http://example.com');
+    }
+
+    private function fetch(string $file)
+    {
+        return $this->connector->fetch(FixtureFactory::createConnectionContext(), $file);
+    }
+}