Use path.join in fetch-latest-parity.js (#489)

scripts/fetch-latest-parity.js

@@ -32,11 +32,16 @@ switch (process.platform) {
 
 const ENDPOINT = `https://vanity-service.parity.io/parity-binaries?os=${os}&architecture=x86_64`;
 
-const STATIC_DIRECTORY = '../packages/fether-electron/static/';
+const STATIC_DIRECTORY = path.join(
+  '..',
+  'packages',
+  'fether-electron',
+  'static'
+);
 
 const foundPath = [
-  path.join(STATIC_DIRECTORY, '/parity'),
-  path.join(STATIC_DIRECTORY, '/parity.exe')
+  path.join(STATIC_DIRECTORY, 'parity'),
+  path.join(STATIC_DIRECTORY, 'parity.exe')
 ].find(existsSync);
 
 if (foundPath) {
@@ -124,7 +129,7 @@ function downloadParity () {
           }
 
           // Write to file and set a+x permissions
-          const destinationPath = `${STATIC_DIRECTORY}/${name}`;
+          const destinationPath = path.join(STATIC_DIRECTORY, name);
           return fsWriteFile(destinationPath, data)
             .then(() => fsChmod(destinationPath, 0o755)) // https://nodejs.org/api/fs.html#fs_fs_chmod_path_mode_callback
             .then(() => destinationPath);