1 files changed, 27 insertions, 9 deletions

diff --git a/lib/utils/path.js b/lib/utils/path.js
index 5285896..c233c92 100644
--- a/lib/utils/path.js
+++ b/lib/utils/path.js
@@ -1,5 +1,12 @@
-var _ = require("lodash");
-var path = require("path");
+var _ = require('lodash');
+var path = require('path');
+
+var error = require('./error');
+
+// Normalize a filename
+function normalizePath(filename) {
+    return path.normalize(filename);
+}
 
 // Return true if file path is inside a folder
 function isInRoot(root, filename) {
@@ -10,31 +17,42 @@ function isInRoot(root, filename) {
 // Resolve paths in a specific folder
 // Throw error if file is outside this folder
 function resolveInRoot(root) {
-    var input, result, err;
+    var input, result;
 
     input = _.chain(arguments)
         .toArray()
         .slice(1)
         .reduce(function(current, p) {
             // Handle path relative to book root ("/README.md")
-            if (p[0] == "/" || p[0] == "\\") return p.slice(1);
+            if (p[0] == '/' || p[0] == '\\') return p.slice(1);
 
             return current? path.join(current, p) : path.normalize(p);
-        }, "")
+        }, '')
         .value();
 
     result = path.resolve(root, input);
 
     if (!isInRoot(root, result)) {
-        err = new Error("EACCESS: \"" + result + "\" not in \"" + root + "\"");
-        err.code = "EACCESS";
-        throw err;
+        throw new error.FileOutOfScopeError({
+            filename: result,
+            root: root
+        });
     }
 
     return result;
 }
 
+// Chnage extension
+function setExtension(filename, ext) {
+    return path.join(
+        path.dirname(filename),
+        path.basename(filename, path.extname(filename)) + ext
+    );
+}
+
 module.exports = {
     isInRoot: isInRoot,
-    resolveInRoot: resolveInRoot
+    resolveInRoot: resolveInRoot,
+    normalize: normalizePath,
+    setExtension: setExtension
 };