Merge pull request #2 from e2/class_builder

Implement Nenv::Builder for creating static classes

Author: e2

Diff for: Gemfile

@@ -8,4 +8,5 @@ gem 'coveralls', require: false
 group :development do
   gem 'guard-rspec', '~> 4.5', require: false
   gem 'guard-rubocop', require: false
+  gem 'pry'
 end

Diff for: README.md

@@ -186,17 +186,29 @@ Nenv.path += Pathname.pwd + "foo"
 
 ```
 
-### Your own class
+### Your own class (recommended version for simpler unit tests)
+
+```ruby
+MyEnv = Nenv::Builder.build do
+  create_method(:foo?)
+end
+
+MyEnv.new('my').foo? # same as ENV['MY_FOO'][/^(?:false|no|n|0)/i,1].nil?
+
+```
+
+
+### Your own class (dynamic version - not recommended because harder to test)
 
 ```ruby
 class MyEnv < Nenv::Environment
   def initialize
-    super("my_env")
+    super("my")
     create_method(:foo?)
   end
 end
 
-MyEnv.new.foo? # same as ENV['MY_ENV_FOO'][/^(?:false|no|n|0)/i,1].nil?
+MyEnv.new.foo? # same as ENV['MY_FOO'][/^(?:false|no|n|0)/i,1].nil?
 
 ```
 

Diff for: lib/nenv.rb

@@ -1,6 +1,7 @@
 require 'nenv/version'
 
 require 'nenv/autoenvironment'
+require 'nenv/builder'
 
 def Nenv(namespace = nil)
   Nenv::AutoEnvironment.new(namespace)

Diff for: lib/nenv/builder.rb

@@ -0,0 +1,9 @@
+require 'nenv/environment'
+
+module Nenv
+  module Builder
+    def self.build(&block)
+      Class.new(Nenv::Environment, &block)
+    end
+  end
+end

Diff for: lib/nenv/environment.rb

@@ -22,26 +22,37 @@ def initialize(namespace = nil)
       @namespace = (namespace ? namespace.upcase : nil)
     end
 
+    def self.create_method(meth, &block)
+      _create_env_method(self, meth, &block)
+    end
+
     def create_method(meth, &block)
-      fail(AlreadyExistsError, meth) if respond_to?(meth)
+      self.class._create_env_method(class << self; self; end, meth, &block)
+    end
+
+    private
+
+    def _sanitize(meth)
+      meth.to_s[/^([^=?]*)[=?]?$/, 1].upcase
+    end
 
-      (class << self; self; end).send(:define_method, meth) do |*args|
-        raw_value = args.first
+    def self._create_env_method(instance, meth, &block)
+      _fail_if_exists(instance, meth)
+
+      instance.send(:define_method, meth) do |*args|
         env_name = [@namespace, _sanitize(meth)].compact.join('_')
 
-        callback = block
         if args.size == 1
-          ENV[env_name] = Dumper.new.dump(raw_value, &callback)
+          raw_value = args.first
+          ENV[env_name] = Dumper.new.dump(raw_value, &block)
         else
-          Loader.new(meth).load(ENV[env_name], &callback)
+          Loader.new(meth).load(ENV[env_name], &block)
         end
       end
     end
 
-    private
-
-    def _sanitize(meth)
-      meth.to_s[/^([^=?]*)[=?]?$/, 1].upcase
+    def self._fail_if_exists(instance, meth)
+      fail(AlreadyExistsError, meth) if instance.instance_methods.include?(meth)
     end
   end
 end

Diff for: spec/lib/nenv/builder_spec.rb

@@ -0,0 +1,27 @@
+require 'nenv/builder'
+
+RSpec.describe Nenv::Builder do
+  describe '#build' do
+    before do
+      allow(ENV).to receive(:[]).with('FOO')
+    end
+
+    it 'returns a class with the given methods' do
+      FooEnv = Nenv::Builder.build do
+        create_method(:foo?)
+      end
+      FooEnv.new.foo?
+    end
+
+    context 'with duplicate methods' do
+      it 'fails' do
+        expect do
+          FooEnv = Nenv::Builder.build do
+            create_method(:foo?)
+            create_method(:foo?)
+          end
+        end.to raise_error(Nenv::Environment::AlreadyExistsError)
+      end
+    end
+  end
+end

Diff for: spec/lib/nenv_spec.rb

@@ -16,7 +16,7 @@
     end
   end
 
-  describe 'Nenv() module' do
+  describe 'Nenv module' do
     it 'reads from env' do
       expect(ENV).to receive(:[]).with('CI').and_return('true')
       Nenv.ci?
@@ -50,4 +50,17 @@
       end
     end
   end
+
+  # Test added here to properly test if builder is required
+  describe 'Nenv builder' do
+    before do
+      allow(ENV).to receive(:[]).with('FOO').and_return('false')
+    end
+    it 'is required and works' do
+      FooEnv = Nenv::Builder.build do
+        create_method(:foo?)
+      end
+      FooEnv.new.foo?
+    end
+  end
 end

Diff for: spec/spec_helper.rb

@@ -10,7 +10,7 @@
     mocks.verify_partial_doubles = true
   end
 
-  config.filter_run :focus
+  config.filter_run focus: ENV['CI'] != 'true'
   config.run_all_when_everything_filtered = true
 
   config.disable_monkey_patching!
@@ -33,6 +33,11 @@
     allow(ENV).to receive(:[]=) do |key, value|
       fail "stub me: ENV[#{key.inspect}] = #{value.inspect}"
     end
+
+    allow(ENV).to receive(:[]).with('PRYRC').and_call_original
+    allow(ENV).to receive(:[]).with('DISABLE_PRY').and_call_original
+    allow(ENV).to receive(:[]).with('ANSICON').and_call_original
+    allow(ENV).to receive(:[]).with('TERM').and_call_original
   end
 
   config.after do