[3.1] Fail parser on preg error

src/Parser.php

@@ -3,6 +3,7 @@
 namespace Dotenv;
 
 use Dotenv\Exception\InvalidFileException;
+use Dotenv\Regex\Regex;
 
 class Parser
 {
@@ -154,9 +155,16 @@ private static function processQuotedValue($value)
             $quote
         );
 
-        $value = (string) preg_replace($pattern, '$1', $value);
-
-        return str_replace('\\\\', '\\', str_replace("\\$quote", $quote, $value));
+        return Regex::pregReplace($pattern, '$1', $value)
+            ->mapSuccess(function ($str) use ($quote) {
+                return str_replace('\\\\', '\\', str_replace("\\$quote", $quote, $str));
+            })
+            ->mapError(function ($err) use ($value) {
+                throw new InvalidFileException(
+                    self::getErrorMessage(sprintf('a quote parsing error (%s)', $err), $value)
+                );
+            })
+            ->getSuccess();
     }
 
     /**

src/Regex/Error.php

@@ -0,0 +1,82 @@
+<?php
+
+namespace Dotenv\Regex;
+
+use PhpOption\None;
+use PhpOption\Some;
+
+class Error extends Result
+{
+    /**
+     * @var string
+     */
+    private $value;
+
+    /**
+     * Internal constructor for an error value.
+     *
+     * @param string $value
+     *
+     * @return void
+     */
+    private function __construct($value)
+    {
+        $this->value = $value;
+    }
+
+    /**
+     * Create a new error value.
+     *
+     * @param string $value
+     *
+     * @return \Dotenv\Regex\Result
+     */
+    public static function create($value)
+    {
+        return new self($value);
+    }
+
+    /**
+     * Get the success option value.
+     *
+     * @return \PhpOption\Option
+     */
+    public function success()
+    {
+        return None::create();
+    }
+
+    /**
+     * Map over the success value.
+     *
+     * @param callable $f
+     *
+     * @return \Dotenv\Regex\Result
+     */
+    public function mapSuccess(callable $f)
+    {
+        return self::create($this->value);
+    }
+
+    /**
+     * Get the error option value.
+     *
+     * @return \PhpOption\Option
+     */
+    public function error()
+    {
+        return Some::create($this->value);
+    }
+
+    /**
+     * Map over the error value.
+     *
+     * @param callable $f
+     *
+     * @return \Dotenv\Regex\Result
+     */
+    public function mapError(callable $f)
+    {
+        return self::create($f($this->value));
+    }
+}

src/Regex/Regex.php

@@ -0,0 +1,54 @@
+<?php
+
+namespace Dotenv\Regex;
+
+use PhpOption\Option;
+
+class Regex
+{
+    /**
+     * Perform a preg replace, failing with an exception.
+     *
+     * @param string $pattern
+     * @param string $repalcement
+     * @param string $subject
+     *
+     * @return \Dotenv\Regex\Result
+     */
+    public static function pregReplace($pattern, $replacement, $subject)
+    {
+        $result = (string) @preg_replace($pattern, $replacement, $subject);
+
+        if (($e = preg_last_error()) !== PREG_NO_ERROR) {
+            return Error::create(self::lookupError($e));
+        }
+
+        return Success::create($result);
+    }
+
+    /**
+     * Lookup the preg error code.
+     *
+     * @param int $code
+     *
+     * @return string
+     */
+    private static function lookupError($code)
+    {
+        return Option::fromValue(get_defined_constants(true))
+            ->filter(function (array $consts) {
+                return isset($consts['pcre']) && defined('ARRAY_FILTER_USE_KEY');
+            })
+            ->map(function (array $consts) {
+                return array_filter($consts['pcre'], function ($msg) {
+                    return substr($msg, -6) === '_ERROR';
+                }, ARRAY_FILTER_USE_KEY);
+            })
+            ->flatMap(function (array $errors) use ($code) {
+                return Option::fromValue(
+                    array_search($code, $errors, true)
+                );
+            })
+            ->getOrElse('PREG_ERROR');
+    }
+}

src/Regex/Result.php

@@ -0,0 +1,58 @@
+<?php
+
+namespace Dotenv\Regex;
+
+abstract class Result
+{
+    /**
+     * Get the success option value.
+     *
+     * @return \PhpOption\Option
+     */
+    abstract public function success();
+
+    /**
+     * Get the error value, if possible.
+     *
+     * @return string
+     */
+    public function getSuccess()
+    {
+        return $this->success()->get();
+    }
+
+    /**
+     * Map over the success value.
+     *
+     * @param callable $f
+     *
+     * @return \Dotenv\Regex\Result
+     */
+    abstract public function mapSuccess(callable $f);
+
+    /**
+     * Get the error option value.
+     *
+     * @return \PhpOption\Option
+     */
+    abstract public function error();
+
+    /**
+     * Get the error value, if possible.
+     *
+     * @return string
+     */
+    public function getError()
+    {
+        return $this->error()->get();
+    }
+
+    /**
+     * Map over the error value.
+     *
+     * @param callable $f
+     *
+     * @return \Dotenv\Regex\Result
+     */
+    abstract public function mapError(callable $f);
+}

src/Regex/Success.php

@@ -0,0 +1,82 @@
+<?php
+
+namespace Dotenv\Regex;
+
+use PhpOption\None;
+use PhpOption\Some;
+
+class Success extends Result
+{
+    /**
+     * @var string
+     */
+    private $value;
+
+    /**
+     * Internal constructor for a success value.
+     *
+     * @param string $value
+     *
+     * @return void
+     */
+    private function __construct($value)
+    {
+        $this->value = $value;
+    }
+
+    /**
+     * Create a new success value.
+     *
+     * @param string $value
+     *
+     * @return \Dotenv\Regex\Result
+     */
+    public static function create($value)
+    {
+        return new self($value);
+    }
+
+    /**
+     * Get the success option value.
+     *
+     * @return \PhpOption\Option
+     */
+    public function success()
+    {
+        return Some::create($this->value);
+    }
+
+    /**
+     * Map over the success value.
+     *
+     * @param callable $f
+     *
+     * @return \Dotenv\Regex\Result
+     */
+    public function mapSuccess(callable $f)
+    {
+        return self::create($f($this->value));
+    }
+
+    /**
+     * Get the error option value.
+     *
+     * @return \PhpOption\Option
+     */
+    public function error()
+    {
+        return None::create();
+    }
+
+    /**
+     * Map over the error value.
+     *
+     * @param callable $f
+     *
+     * @return \Dotenv\Regex\Result
+     */
+    public function mapError(callable $f)
+    {
+        return self::create($this->value);
+    }
+}

tests/Dotenv/ParserTest.php

@@ -15,6 +15,11 @@ public function testQuotesParse()
         $this->assertSame(['FOO', "BAR  \n"], Parser::parse("FOO=\"BAR  \n\""));
     }
 
+    public function testWhitespaceParse()
+    {
+        $this->assertSame(['FOO', "\n"], Parser::parse("FOO=\"\n\""));
+    }
+
     public function testExportParse()
     {
         $this->assertSame(['FOO', 'bar baz'], Parser::parse('export FOO="bar baz"'));
@@ -46,4 +51,19 @@ public function testParseInvalidName()
     {
         Parser::parse('FOO_ASD!=BAZ');
     }
+
+    /**
+     * @expectedException \Dotenv\Exception\InvalidFileException
+     * @expectedExceptionMessage Failed to parse dotenv file due to a quote parsing error (PREG_
+     */
+    public function testParserFailsWithException()
+    {
+        $limit = (int) ini_get('pcre.backtrack_limit');
+
+        if ($limit > 1000000) {
+            $this->markTestSkipped('System pcre.backtrack_limit too large.');
+        }
+
+        Parser::parse('FOO_BAD="iiiiviiiixiiiiviiii\\n"');
+    }
 }

tests/Dotenv/ResultTest.php

@@ -0,0 +1,58 @@
+<?php
+
+use DotEnv\Regex\Error;
+use DotEnv\Regex\Success;
+use PHPUnit\Framework\TestCase;
+
+class ResultTest extends TestCase
+{
+    public function testSuccessValue()
+    {
+        $this->assertTrue(Success::create('foo')->error()->isEmpty());
+        $this->assertTrue(Success::create('foo')->success()->isDefined());
+        $this->assertEquals('foo', Success::create('foo')->getSuccess());
+    }
+
+    public function testSuccessMapping()
+    {
+        $r = Success::create('foo')
+            ->mapSuccess('strtoupper')
+            ->mapError('ucfirst');
+
+        $this->assertEquals('FOO', $r->getSuccess());
+    }
+
+    /**
+     * @expectedException \RuntimeException
+     * @expectedExceptionMessage None has no value.
+     */
+    public function testSuccessFail()
+    {
+        Success::create('foo')->getError();
+    }
+
+    public function testErrorValue()
+    {
+        $this->assertTrue(Error::create('foo')->error()->isDefined());
+        $this->assertTrue(Error::create('foo')->success()->isEmpty());
+        $this->assertEquals('foo', Error::create('foo')->getError());
+    }
+
+    public function testErrorMapping()
+    {
+        $r = Error::create('foo')
+            ->mapSuccess('strtoupper')
+            ->mapError('ucfirst');
+
+        $this->assertEquals('Foo', $r->getError());
+    }
+
+    /**
+     * @expectedException \RuntimeException
+     * @expectedExceptionMessage None has no value.
+     */
+    public function testErrorFail()
+    {
+        Error::create('foo')->getSuccess();
+    }
+}