Do not use GITLAB_RELEASE env to define QA strategy

[ci skip]

qa/Dockerfile

 FROM ruby:2.3
 LABEL maintainer "Grzegorz Bizon <grzegorz@gitlab.com>"
 
-ENV GITLAB_RELEASE CE
-
 RUN sed -i "s/httpredir.debian.org/ftp.us.debian.org/" /etc/apt/sources.list && \
     apt-get update && apt-get install -y --force-yes \
       libqt5webkit5-dev qt5-qmake qt5-default build-essential xvfb git && \

qa/qa/runtime/release.rb

@@ -2,35 +2,32 @@ module QA
   module Runtime
     ##
     # Class that is responsible for plugging CE/EE extensions in, depending on
-    # environment variable GITLAB_RELEASE that should be present in the runtime
-    # environment.
+    # existence of EE module.
     #
     # We need that to reduce the probability of conflicts when merging
     # CE to EE.
     #
     class Release
-      UnspecifiedReleaseError = Class.new(StandardError)
-
-      def initialize(version = ENV['GITLAB_RELEASE'])
-        @version = version.to_s.upcase
-
-        unless %w[CE EE].include?(@version)
-          raise UnspecifiedReleaseError, 'GITLAB_RELEASE env not defined!'
-        end
+      def initialize(variant = nil)
+        @version = variant || version
 
         begin
-          require "qa/#{version.downcase}/strategy"
+          require "qa/#{@version.downcase}/strategy"
         rescue LoadError
           # noop
         end
       end
 
+      def version
+        File.directory?("#{__dir__}/../ee") ? :EE : :CE
+      end
+
       def has_strategy?
-        QA.const_defined?("#{@version}::Strategy")
+        QA.const_defined?("QA::#{@version}::Strategy")
       end
 
       def strategy
-        QA.const_get("#{@version}::Strategy")
+        QA.const_get("QA::#{@version}::Strategy")
       end
 
       def self.method_missing(name, *args)

qa/spec/runtime/release_spec.rb

 describe QA::Runtime::Release do
   context 'when release version has extension strategy' do
-    subject { described_class.new('CE') }
-    let(:strategy) { spy('CE::Strategy') }
+    subject { described_class.new('VER') }
+    let(:strategy) { spy('VER::Strategy') }
 
     before do
-      stub_const('QA::CE::Strategy', strategy)
-      stub_const('QA::EE::Strategy', strategy)
+      stub_const('QA::VER::Strategy', strategy)
     end
 
     describe '#has_strategy?' do
@@ -16,11 +15,19 @@ describe QA::Runtime::Release do
 
     describe '#strategy' do
       it 'return the strategy constant' do
-        expect(subject.strategy).to eq QA::CE::Strategy
+        expect(subject.strategy).to eq QA::VER::Strategy
       end
     end
 
     describe 'delegated class methods' do
+      before do
+        allow_any_instance_of(described_class)
+          .to receive(:has_strategy?).and_return(true)
+
+        allow_any_instance_of(described_class)
+          .to receive(:strategy).and_return(strategy)
+      end
+
       it 'delegates all calls to strategy class' do
         described_class.some_method(1, 2)
 
@@ -31,12 +38,7 @@ describe QA::Runtime::Release do
   end
 
   context 'when release version does not have extension strategy' do
-    subject { described_class.new('CE') }
-
-    before do
-      hide_const('QA::CE::Strategy')
-      hide_const('QA::EE::Strategy')
-    end
+    subject { described_class.new('NOVER') }
 
     describe '#has_strategy?' do
       it 'returns false' do
@@ -50,18 +52,23 @@ describe QA::Runtime::Release do
       end
     end
 
-    describe 'delegated class methods' do
+    describe 'does not delegate class methods' do
+      before do
+        allow_any_instance_of(described_class)
+          .to receive(:has_strategy?).and_return(false)
+      end
+
       it 'behaves like a null object and does nothing' do
         expect { described_class.some_method(2, 3) }.not_to raise_error
       end
-    end
-  end
 
-  context 'when release version is invalid or unspecified' do
-    describe '#new' do
-      it 'raises an exception' do
-        expect { described_class.new(nil) }
-          .to raise_error(described_class::UnspecifiedReleaseError)
+      it 'returns nil' do
+        expect(described_class.something).to be_nil
+      end
+
+      it 'does not delegate to strategy object' do
+        expect_any_instance_of(described_class)
+          .not_to receive(:strategy)
       end
     end
   end