feat: modify generators and update readme

Author: KonnorRogers

README.md

@@ -25,15 +25,17 @@ gem 'snowpacker'
 
 Then run
 
-    $ bin/rails g snowpacker
+```
+bin/rails g snowpacker
+```
 
 ### Development
 
 Currently `snowpacker` is not integrated with `rails s` so you need a process manager like [foreman]() to run both `rails s` and `snowpack`.
 
 Create `Procfile.dev`, with the following content:
 
-```
+```bash
 web: bin/rails s
 snowpacker: bin/rails snowpacker:serve
 ```
@@ -46,21 +48,28 @@ Gem hooks up to the `assets:precompile` and `assets:clobber`, so no special setu
 
 You can start snowpacker's compilation process manually by running
 
-    rake snowpacker:compile
+```bash
+rake snowpacker:compile
+```
 
 ### Including in views
 
 Use Rails generic helpers to include assets in your views
 
-    javascript_include_tag '/snowpacks/application'
-    stylesheet_link_tag '/snowpacks/application'
+```ruby
+<%= javascript_snowpack_tag 'application' %> # => snowpacks/javascript
+<%= stylesheet_snowpack_tag 'application' %> # => snowpacks/stylesheets
+```
 
 ### Configuration
 
-After running generator, configuration can be found in config/initializers/snowpacker.rb.
+After running generator, the configuration file can be found in
+`config/initializers/snowpacker.rb`
 
-	config.snowpacker.entry_points = %w(app/javascript/application.js)
-	config.snowpacker.destination = 'public/snowpacks'
+```ruby
+config.snowpacker.entry_points = %w(app/javascript/snowpacks/application.js)
+config.snowpacker.destination = 'snowpacks'
+```
 
 ## Changelog
 

examples/railsapp/config/initializers/snowpacker.rb

@@ -0,0 +1,4 @@
+Rails.application.config.snowpacker do |snowpacker|
+  snowpacker.entry_points = %w(app/javascript/snowpacks/application.js)
+  snowpacker.destination = 'snowpacks'
+end

examples/railsapp/package.json

@@ -15,6 +15,7 @@
   "devDependencies": {
     "@snowpack/plugin-babel": "^1.4.0",
     "@snowpack/plugin-parcel": "^1.3.0",
+    "parcel-bundler": "^1.12.4",
     "snowpack": "^2.6.4",
     "webpack-dev-server": "^3.11.0"
   }

examples/railsapp/yarn.lock

@@ -4969,7 +4969,7 @@ pako@~1.0.5:
   resolved "https://registry.yarnpkg.com/pako/-/pako-1.0.11.tgz#6c9599d340d54dfd3946380252a35705a6b992bf"
   integrity sha512-4hLB8Py4zZce5s4yd9XzopqwVv/yGNhV1Bl8NTmCq1763HeK2+EwVTv+leGeL13Dnh2wfbqowVPXCIO0z4taYw==
 
-parcel-bundler@^1.0.0:
+parcel-bundler@^1.0.0, parcel-bundler@^1.12.4:
   version "1.12.4"
   resolved "https://registry.yarnpkg.com/parcel-bundler/-/parcel-bundler-1.12.4.tgz#31223f4ab4d00323a109fce28d5e46775409a9ee"
   integrity sha512-G+iZGGiPEXcRzw0fiRxWYCKxdt/F7l9a0xkiU4XbcVRJCSlBnioWEwJMutOCCpoQmaQtjB4RBHDGIHN85AIhLQ==

lib/snowpacker/rails/snowpacker_generator.rb

@@ -14,7 +14,9 @@ def create_initializer_file
   end
 
   def add_snowpack
-    `yarn add snowpack parcel-bundler \
-              @snowpack/plugin-babel @snowpack/plugin-parcel`
+    `yarn add -D snowpack \
+                 parcel-bundler \
+                 @snowpack/plugin-babel \
+                 @snowpack/plugin-parcel`
   end
 end