Dictionary show action for letters, alphabetical links helper

Gemfile

@@ -51,6 +51,7 @@ group :development, :test do
   # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem
   gem "debug", platforms: %i[ mri windows ]
   gem "rspec-rails"
+  gem "capybara"
   gem "rails-controller-testing"
   gem "factory_bot_rails"
 end

Gemfile.lock

@@ -83,6 +83,15 @@ GEM
     bootsnap (1.16.0)
       msgpack (~> 1.2)
     builder (3.2.4)
+    capybara (3.39.2)
+      addressable
+      matrix
+      mini_mime (>= 0.1.3)
+      nokogiri (~> 1.8)
+      rack (>= 1.6.0)
+      rack-test (>= 0.6.3)
+      regexp_parser (>= 1.5, < 3.0)
+      xpath (~> 3.2)
     concurrent-ruby (1.2.2)
     connection_pool (2.4.1)
     crass (1.0.6)
@@ -145,6 +154,7 @@ GEM
       net-pop
       net-smtp
     marcel (1.0.2)
+    matrix (0.4.2)
     mini_mime (1.1.5)
     minitest (5.20.0)
     msgpack (1.7.2)
@@ -216,6 +226,7 @@ GEM
     rake (13.0.6)
     rdoc (6.5.0)
       psych (>= 4.0.0)
+    regexp_parser (2.8.2)
     reline (0.3.9)
       io-console (~> 0.5)
     responders (3.1.1)
@@ -274,6 +285,8 @@ GEM
     websocket-driver (0.7.6)
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.5)
+    xpath (3.2.0)
+      nokogiri (~> 1.8)
     zeitwerk (2.6.12)
 
 PLATFORMS
@@ -283,6 +296,7 @@ PLATFORMS
 
 DEPENDENCIES
   bootsnap
+  capybara
   debug
   devise
   factory_bot_rails

app/controllers/dictionary_controller.rb

@@ -3,4 +3,9 @@ class DictionaryController < ApplicationController
     @parts_of_speech = PartOfSpeech.all
     @words = Word.all
   end
+
+  def show
+    @letter = params[:id]
+    @words = Word.where('substr(word, 1, 1) = ?', @letter)
+  end
 end

app/helpers/dictionary_helper.rb

@@ -1,2 +1,10 @@
 module DictionaryHelper
+  LETTERS = ['i', 'u', 'e', 'o', 'a', 'm', 'n', 'p', 't', 'k', 's', 'w', 'l', 'j'].sort
+
+  def alphabetical_links
+
+    LETTERS.map do |l|
+      link_to l.to_s, dictionary_path(l)
+    end.join("\n")
+  end
 end

app/views/dictionary/index.html.erb

@@ -1,6 +1,8 @@
 <h1>Dictionary#index</h1>
 <p>Find me in app/views/dictionary/index.html.erb</p>
 
+<%= sanitize alphabetical_links, tags: ["a"] %>
+
 <p><%= @parts_of_speech.count %> parts of speech entries in database</p>
 <h1>Parts of Speech</h1>
 <table>

app/views/dictionary/show.html.erb

@@ -0,0 +1,9 @@
+<div>
+  <%= @letter.to_s %>
+</div>
+
+<% @words.each do |word| %>
+  <div>
+    <h1><%= word.word %></h1>
+  </div>
+<% end %>

config/routes.rb

@@ -1,7 +1,7 @@
 Rails.application.routes.draw do
   devise_for :users
   #get 'dictionary/index'
-  resources :dictionary, only: [:index]
+  resources :dictionary, only: [:index, :show]
   resources :words, only: [:index, :show]
   # Define your application routes per the DSL in https://guides.rubyonrails.org/routing.html
 

spec/helpers/dictionary_helper_spec.rb

@@ -0,0 +1,36 @@
+require 'rails_helper'
+
+include Capybara::RSpecMatchers
+
+# Specs in this file have access to a helper object that includes
+# the DictionaryHelper. For example:
+#
+# describe DictionaryHelper do
+#   describe "string concat" do
+#     it "concats two strings with spaces" do
+#       expect(helper.concat_strings("this","that")).to eq("this that")
+#     end
+#   end
+# end
+RSpec.describe DictionaryHelper, type: :helper do
+
+  describe "#alphabetical_links" do
+
+    it "generates fourteen letter-links" do
+      expect(helper.alphabetical_links).to have_selector(%(a), count: 14)
+    end
+
+    it "generates links for all fourteen letters" do
+      output = helper.alphabetical_links
+      letters = ['i', 'u', 'e', 'o', 'a', 'm', 'n', 'p', 't', 'k', 's', 'w', 'l', 'j']
+
+      letters.each do |l|
+        expect(output).to have_link(l, href: dictionary_path(l))
+      end
+    end
+
+    it "sorts the toki pona alphabet" do
+      expect(DictionaryHelper::LETTERS).to eql(DictionaryHelper::LETTERS.sort)
+    end
+  end
+end

spec/requests/dictionary_spec.rb

@@ -7,4 +7,21 @@ RSpec.describe "Dictionary", type: :request do
       expect(response).to render_template(:index)
     end
   end
+
+  describe "GET /show" do
+    it 'renders the show template' do
+      get "/dictionary/a"
+      expect(response).to render_template(:show)
+    end
+
+    it "sets @letter instance variable" do
+      get "/dictionary/a"
+      expect(assigns(:letter)).to be_a(String)
+    end
+
+    it "sets @words instance variable" do
+      get "/dictionary/a"
+      expect(assigns(:words)).to be_a(ActiveRecord::Relation)
+    end
+  end
 end