Fix maxBytes check

Author: mzur

src/FileCache.php

@@ -565,16 +565,19 @@ protected function cacheFromResource(File $file, $source, $target)
 
         $cachedPath = $this->getCachedPath($file);
         $maxBytes = intval($this->config['max_file_size']);
-        $bytes = stream_copy_to_stream($source, $target, $maxBytes);
-
-        if ($bytes === $maxBytes) {
-            throw new Exception("The file is too large with more than {$maxBytes} bytes.");
-        }
+        // Copy one byte more than allowed to detect files that exceed the limit.
+        // Using $maxBytes directly would reject files of exactly $maxBytes bytes.
+        $copyLimit = $maxBytes >= 0 ? $maxBytes + 1 : -1;
+        $bytes = stream_copy_to_stream($source, $target, $copyLimit);
 
         if ($bytes === false) {
             throw new Exception('The source resource is invalid.');
         }
 
+        if ($maxBytes >= 0 && $bytes > $maxBytes) {
+            throw new Exception("The file is too large with more than {$maxBytes} bytes.");
+        }
+
         $metadata = stream_get_meta_data($source);
 
         if (array_key_exists('timed_out', $metadata) && $metadata['timed_out']) {

tests/FileCacheTest.php

@@ -95,6 +95,22 @@ public function testGetRemoteTooLarge()
         $this->assertFalse(is_resource($cache->stream));
     }
 
+    public function testGetRemoteExactlyMaxSize()
+    {
+        $file = new GenericFile('https://files/image.jpg');
+        $cache = new FileCacheStub([
+            'path' => $this->cachePath,
+            'max_file_size' => 3,
+        ]);
+
+        $stream = fopen('php://temp', 'r+');
+        fwrite($stream, 'abc');
+        rewind($stream);
+        $cache->stream = $stream;
+        $path = $cache->get($file, $this->noop);
+        $this->assertEquals(3, filesize($path));
+    }
+
     public function testGetDiskDoesNotExist()
     {
         $file = new GenericFile('abc://files/image.jpg');
@@ -180,6 +196,31 @@ public function testGetDiskCloudTooLarge()
         $this->assertFalse(is_resource($stream));
     }
 
+    public function testGetDiskCloudExactlyMaxSize()
+    {
+        config(['filesystems.disks.s3' => ['driver' => 's3']]);
+        $file = new GenericFile('s3://files/image.txt');
+        $hash = hash('sha256', 's3://files/image.txt');
+
+        $stream = fopen('php://temp', 'r+');
+        fwrite($stream, 'abc');
+        rewind($stream);
+
+        $mock = Mockery::mock();
+        $mock->shouldReceive('disk')->once()->with('s3')->andReturn($mock);
+        $mock->shouldReceive('readStream')->once()->andReturn($stream);
+        $this->app['filesystem'] = $mock;
+
+        $cache = new FileCache([
+            'path' => $this->cachePath,
+            'max_file_size' => 3,
+        ]);
+
+        $path = $cache->get($file, $this->noop);
+        $this->assertEquals(3, filesize($path));
+        $this->assertFalse(is_resource($stream));
+    }
+
     public function testGetThrowOnLock()
     {
         $cache = new FileCache(['path' => $this->cachePath]);