message: also test provided_path
diff: extern crate dir_diff;
  extern crate wasm_pack;
  -use std::fs;
  -
  #[test]
  fn it_gets_the_crate_name_default_path() {
  assert!(wasm_pack::get_crate_name(".").is_ok());
  @@ -27,5 +25,8 @@ fn it_creates_a_package_json_default_path() {
  #[test]
  fn it_creates_a_package_json_provided_path() {
  assert!(wasm_pack::write_package_json("./examples/js-hello-world").is_ok());
  - assert!(fs::metadata("./examples/js-hello-world/pkg/package.json").is_ok());
  + assert!(!dir_diff::is_different(
  + "./examples/js-hello-world/pkg",
  + "./test/fixtures/package-json"
  + ).unwrap());
  }
  