Avoiding stat of file with realpath

cfphpflex · Apr 3, 2015 · d921ca3 · d921ca3
1 parent 6d43be8
commit d921ca3
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Showing 2 changed files with 68 additions and 1 deletion.
diff --git a/src/JsonCompiler.php b/src/JsonCompiler.php
@@ -73,7 +73,7 @@ public function load($path)
             return json_decode(file_get_contents($path), true);
         }
 
-        $real = realpath($path);
+        $real = $this->normalize($path);
         $cache = str_replace($this->stripPath, '', $real);
         $cache = str_replace(['\\', '/'], '_', $cache);
         $cache = $this->cacheDir . DIRECTORY_SEPARATOR . $cache . '.php';
@@ -93,4 +93,44 @@ public function load($path)
 
         return $data;
     }
+
+    /**
+     * Resolve relative paths without using realpath (which causes an
+     * unnecessary fstat).
+     *
+     * @param $path
+     *
+     * @return string
+     */
+    private function normalize($path)
+    {
+        static $replace = ['/', '\\'];
+
+        $parts = explode(
+            DIRECTORY_SEPARATOR,
+            // Normalize path separators
+            str_replace($replace, DIRECTORY_SEPARATOR, $path)
+        );
+
+        $segments = [];
+        foreach ($parts as $part) {
+            if ($part === '' || $part === '.') {
+                continue;
+            }
+            if ($part === '..') {
+                array_pop($segments);
+            } else {
+                $segments[] = $part;
+            }
+        }
+
+        $resolved = implode(DIRECTORY_SEPARATOR, $segments);
+
+        // Add a leading slash if necessary.
+        if (isset($parts[0]) && $parts[0] === '') {
+            $resolved = DIRECTORY_SEPARATOR . $resolved;
+        }
+
+        return $resolved;
+    }
 }
diff --git a/tests/JsonCompilerTest.php b/tests/JsonCompilerTest.php
@@ -73,4 +73,31 @@ public function testCanPurgeCachedFiles()
         $entries = array_diff(scandir($c->getCacheDir()), ['.', '..']);
         $this->assertEmpty($entries);
     }
+
+    public function pathProvider()
+    {
+        return [
+            ['/foo/baz/bar.qux', '/foo/baz/bar.qux'],
+            ['/foo/baz/../bar.qux', '/foo/bar.qux'],
+            ['/foo/baz/./bar.qux', '/foo/baz/bar.qux'],
+            ['/foo/baz/../../bar.qux', '/bar.qux'],
+            ['/../../bar.qux', '/bar.qux'],
+            // Extra slashes
+            ['/foo//baz///bar.qux', '/foo/baz/bar.qux'],
+            // Relative with no leading slash
+            ['foo/baz/../bar.qux', 'foo/bar.qux'],
+            ['\\foo\\baz\\..\\.\\bar.qux', '/foo/bar.qux'],
+        ];
+    }
+
+    /**
+     * @dataProvider pathProvider
+     */
+    public function testResolvesRelativePaths($path, $resolved)
+    {
+        $j = new JsonCompiler();
+        $meth = new \ReflectionMethod('Aws\JsonCompiler', 'normalize');
+        $meth->setAccessible(true);
+        $this->assertEquals($resolved, $meth->invoke($j, $path));
+    }
 }