Refactoring file handling with minimum backward compatibility breaks

Filesystem/AbstractCommonResource.php

@@ -0,0 +1,191 @@
+<?php declare(strict_types=1);
+
+namespace CleverAge\ProcessBundle\Filesystem;
+
+/**
+ * Common methods for readers using resources
+ */
+abstract class AbstractCommonResource implements FileStreamInterface
+{
+    /** @var resource */
+    protected $handler;
+
+    /** @var int|null */
+    protected $lineCount;
+
+    /** @var int */
+    protected $lineNumber = 1;
+
+    /** @var bool */
+    protected $closed;
+
+    /** @var bool */
+    protected $seekCalled = false;
+
+    /**
+     * @param resource $resource
+     *
+     * @throws \UnexpectedValueException
+     */
+    public function __construct($resource)
+    {
+        if (!\is_resource($resource)) {
+            $type = \gettype($resource);
+            throw new \UnexpectedValueException("Resource argument must be a resource, '{$type}' given");
+        }
+        $this->handler = $resource;
+    }
+
+    /**
+     * @return resource
+     */
+    public function getHandler()
+    {
+        return $this->handler;
+    }
+
+    /**
+     * Warning! This method will rewind the file to the beginning before and after counting the lines!
+     *
+     * @throws \RuntimeException
+     *
+     * @return int
+     */
+    public function getLineCount(): int
+    {
+        if (null === $this->lineCount) {
+            $this->rewind();
+            $line = 0;
+            while (!$this->isEndOfFile()) {
+                ++$line;
+                $this->readRaw();
+            }
+            $this->rewind();
+
+            $this->lineCount = $line;
+        }
+
+        return $this->lineCount;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function getLineNumber(): int
+    {
+        if ($this->seekCalled) {
+            throw new \LogicException('Cannot get current line number after calling "seek": the line number is lost');
+        }
+
+        return $this->lineNumber;
+    }
+
+    /**
+     * @throws \RuntimeException
+     *
+     * @return bool
+     */
+    public function isEndOfFile(): bool
+    {
+        $this->assertOpened();
+
+        return feof($this->handler);
+    }
+
+    /**
+     * Warning, this function will return exactly the same value as the internal function used by the subsystem.
+     *
+     * @param null|int $length
+     *
+     * @throws \RuntimeException
+     *
+     * @return mixed
+     */
+    abstract public function readRaw($length = null);
+
+    /**
+     * This methods rewinds the file to the first line of data, skipping the headers.
+     *
+     * @throws \RuntimeException
+     */
+    public function rewind(): void
+    {
+        $this->assertOpened();
+        if (!rewind($this->handler)) {
+            throw new \RuntimeException("Unable to rewind '{$this->getResourceName()}'");
+        }
+        $this->lineNumber = 1;
+    }
+
+    /**
+     * @throws \RuntimeException
+     *
+     * @return int
+     */
+    public function tell(): int
+    {
+        $this->assertOpened();
+
+        return ftell($this->handler);
+    }
+
+    /**
+     * @param int $offset
+     *
+     * @throws \RuntimeException
+     *
+     * @return int
+     */
+    public function seek($offset): int
+    {
+        $this->assertOpened();
+        $this->seekCalled = true;
+
+        return fseek($this->handler, $offset);
+    }
+
+    /**
+     * @return bool
+     */
+    public function close(): bool
+    {
+        if ($this->closed) {
+            return true;
+        }
+
+        $this->closed = fclose($this->handler);
+
+        return $this->closed;
+    }
+
+    /**
+     * @return bool
+     */
+    public function isClosed(): bool
+    {
+        return $this->closed;
+    }
+
+    /**
+     * Closes the resource when the object is destroyed.
+     */
+    public function __destruct()
+    {
+        $this->close();
+    }
+
+    /**
+     * @throws \RuntimeException
+     */
+    protected function assertOpened(): void
+    {
+        if ($this->closed) {
+            throw new \RuntimeException("{$this->getResourceName()} was closed earlier");
+        }
+    }
+
+    /**
+     * @return string
+     */
+    abstract protected function getResourceName(): string;
+}

Filesystem/CsvFile.php

@@ -18,6 +18,8 @@
  */
 class CsvFile extends CsvResource
 {
+    use FileHelperTrait;
+
     /** @var string */
     protected $filePath;
 
@@ -41,18 +43,8 @@ public function __construct(
         $mode = 'rb'
     ) {
         $this->filePath = $filePath;
+        $resource = $this->openResource($filePath, $mode);
 
-        if (!\in_array($filePath, ['php://stdin', 'php://stdout', 'php://stderr'])) {
-            $dirname = \dirname($this->filePath);
-            if (!@mkdir($dirname, 0755, true) && !is_dir($dirname)) {
-                throw new \RuntimeException(sprintf('Directory "%s" was not created', $dirname));
-            }
-        }
-
-        $resource = fopen($filePath, $mode);
-        if (false === $resource) {
-            throw new \UnexpectedValueException("Unable to open file: '{$filePath}' in {$mode} mode");
-        }
         // All modes allowing file reading, binary safe modes are handled by stripping out the b during test
         $readAllowedModes = ['r', 'r+', 'w+', 'a+', 'x+', 'c+'];
         if (null === $headers && !\in_array(str_replace('b', '', $mode), $readAllowedModes, true)) {