docs: describe --lang arg

docs/en/create-hermione-app.md

@@ -4,12 +4,6 @@ Use `create-hermione-app` to set up [hermione](https://github.com/gemini-testing
 
 ## Usage
 
-```bash
-npx create-hermione-app my-app
-```
-
-or via `npm init`:
-
 ```bash
 npm init hermione-app my-app
 ```
@@ -22,7 +16,11 @@ If you already have a project at given path, the tool will try to guess used pac
 
 ### No questions mode
 
-You can add `-y` or `--yes` argument to launch a tool in *no-questions* mode.
+You can add `-y` or `--yes` argument to launch a tool in *no-questions* mode:
+
+```bash
+npm init hermione-app my-app -- -y
+```
 
 In this mode you won't be asked questions about desired plugins and packet manager.
 
@@ -31,6 +29,16 @@ Default packet manager, used with `--yes` argument: `npm`
 Default plugins, installed with `--yes` argument: 
 - [html-reporter](https://github.com/gemini-testing/html-reporter)
 
+### Lang
+
+By default, create-hermione-app sets up project with typescript tests support.
+
+You can opt-out of typescript by adding `--lang js` argument:
+
+```bash
+npm init hermione-app my-app -- --lang js
+```
+
 ## List of proposed plugins
 
 - [Global Hook](https://github.com/gemini-testing/hermione-global-hook) - To add global 'beforeEach' and 'afterEach' functions

docs/ru/create-hermione-app.md

@@ -4,12 +4,6 @@
 
 ## Использование
 
-```bash
-npx create-hermione-app my-app
-```
-
-Или через `npm init`:
-
 ```bash
 npm init hermione-app my-app
 ```
@@ -31,6 +25,16 @@ npm init hermione-app my-app
 Плагины по умолчанию, устанавливаемые с аргументом `--yes`: 
 - [html-reporter](https://github.com/gemini-testing/html-reporter)
 
+### Язык
+
+По умолчанию create-hermione-app настраивает проект с поддержкой typescript тестов.
+
+Вы можете отказаться от использования typescript, добавив аргумент `--lang js`:
+
+```bash
+npm init hermione-app my-app -- --lang js
+```
+
 ## Список предлагаемых плагинов
 
 - [Global Hook](https://github.com/gemini-testing/hermione-global-hook) - Чтобы вынести общую логику из своих тестов в специальные обработчики для `beforeEach` и `afterEach` хуков

src/bin/create-hermione-app.ts

@@ -26,5 +26,5 @@ const argv = yargs(hideBin(process.argv))
     .parse();
 
 const argvOpts = optsFromArgv(argv as ToolArgv);
-const createOpts = (defaultOpts: DefaultOpts): ToolOpts => Object.assign(argvOpts, defaultOpts);
+const createOpts = (defaultOpts: DefaultOpts): ToolOpts => ({ ...defaultOpts, ...argvOpts });
 launcher.run({ createOpts });