Fix some errors, update README

README.md

@@ -17,6 +17,7 @@ validating proxy lists from the different providers. [Checkout examples](#standa
 
 ## Table of Contents
 
+- [Dependencies](#dependencies)
 - [Installation](#installation)
 - [Example of usage](#example-of-usage)
   - [In Ruby application](#in-ruby-application)
@@ -29,6 +30,18 @@ validating proxy lists from the different providers. [Checkout examples](#standa
 - [Contributing](#contributing)
 - [License](#license)
 
+## Dependencies
+
+ProxyFetcher gem itself requires only Ruby `>= 2.0.0`.
+
+However, it requires an adapter to parse HTML. If you do not specify any specific adapter, then it will use
+default one - [Nokogiri](https://github.com/sparklemotion/nokogiri). It's OK for any Ruby on Rails project
+(because they uses it by default).
+
+But if you want to use some specific adapter (for example your Ruby application uses [Oga](https://gitlab.com/yorickpeterse/oga),
+then you need to manually add your dependencies to your project and configure ProxyFetcher to use another adapter. Moreover,
+you can implement your own adapter if it your use-case. Take a look at the [Configuration](#configuration) section for more details.
+
 ## Installation
 
 If using bundler, first add 'proxy_fetcher' to your Gemfile:

lib/proxy_fetcher/document/adapters/abstract_adapter.rb

@@ -24,7 +24,7 @@ def proxy_node
       def self.setup!(*args)
         install_requirements!(*args)
       rescue LoadError => error
-        raise Exceptions::AdapterSetupError.new(self.class.name, error.message)
+        raise Exceptions::AdapterSetupError.new(name, error.message)
       end
     end
   end

lib/proxy_fetcher/exceptions.rb

@@ -51,7 +51,7 @@ def initialize(*)
 
     class AdapterSetupError < Error
       def initialize(adapter_name, reason)
-        adapter = demodulize(adapter_name.remove('Adapter'))
+        adapter = demodulize(adapter_name.gsub('Adapter', ''))
 
         super("can't setup '#{adapter}' adapter during the following error:\n\t#{reason}'")
       end
@@ -62,11 +62,7 @@ def demodulize(path)
         path = path.to_s
         index = path.rindex('::')
 
-        if index
-          path[(index + 2)..-1]
-        else
-          path
-        end
+        index ? path[(index + 2)..-1] : path
       end
     end
   end

proxy_fetcher.gemspec

@@ -5,7 +5,7 @@ require 'proxy_fetcher/version'
 Gem::Specification.new do |gem|
   gem.name = 'proxy_fetcher'
   gem.version = ProxyFetcher.gem_version
-  gem.date = '2017-12-05'
+  gem.date = '2017-12-08'
   gem.summary = 'Ruby gem for dealing with proxy lists from different providers'
   gem.description = 'This gem can help your Ruby application to make HTTP(S) requests ' \
                     'using proxies by fetching and validating proxy lists from the different providers.'

spec/proxy_fetcher/configuration_spec.rb

@@ -43,16 +43,33 @@ def self.connectable?(*)
   end
 
   context 'custom provider' do
-    it 'failed on registration if provider class already registered' do
+    it 'fails on registration if provider class already registered' do
       expect { ProxyFetcher::Configuration.register_provider(:xroxy, Class.new) }
         .to raise_error(ProxyFetcher::Exceptions::RegisteredProvider)
     end
 
-    it "failed on proxy list fetching if provider doesn't registered" do
+    it "fails on proxy list fetching if provider doesn't registered" do
       ProxyFetcher.config.provider = :not_existing_provider
 
       expect { ProxyFetcher::Manager.new }
         .to raise_error(ProxyFetcher::Exceptions::UnknownProvider)
     end
   end
+
+  context 'custom HTML parsing adapter' do
+    it "fails if adapter can't be installed" do
+      old_config = ProxyFetcher.config.dup
+
+      class CustomAdapter < ProxyFetcher::Document::AbstractAdapter
+        def self.install_requirements!
+          require 'not_existing_gem'
+        end
+      end
+
+      expect { ProxyFetcher.config.adapter = CustomAdapter }
+        .to raise_error(ProxyFetcher::Exceptions::AdapterSetupError)
+
+      ProxyFetcher.instance_variable_set('@config', old_config)
+    end
+  end
 end