Flatten Entry::Script elements

Flattens Entry::Script elements so we can use YAML anchors as part of
the before_script and after_script definition.

lib/gitlab/ci/config/entry/script.rb

@@ -11,7 +11,11 @@ module Gitlab
           include ::Gitlab::Config::Entry::Validatable
 
           validations do
-            validates :config, array_of_strings: true
+            validates :config, array_of_strings_or_arrays_of_strings: true
+          end
+
+          def value
+            config.flatten
           end
         end
       end

spec/lib/gitlab/ci/config/entry/script_spec.rb

@@ -6,7 +6,7 @@ describe Gitlab::Ci::Config::Entry::Script do
   let(:entry) { described_class.new(config) }
 
   describe 'validations' do
-    context 'when entry config value is correct' do
+    context 'when entry config value is array of strings' do
       let(:config) { %w(ls pwd) }
 
       describe '#value' do
@@ -28,13 +28,57 @@ describe Gitlab::Ci::Config::Entry::Script do
       end
     end
 
+    context 'when entry config value is array of arrays of strings' do
+      let(:config) { [['ls'], ['pwd', 'echo 1']] }
+
+      describe '#value' do
+        it 'returns array of strings' do
+          expect(entry.value).to eq ['ls', 'pwd', 'echo 1']
+        end
+      end
+
+      describe '#errors' do
+        it 'does not append errors' do
+          expect(entry.errors).to be_empty
+        end
+      end
+
+      describe '#valid?' do
+        it 'is valid' do
+          expect(entry).to be_valid
+        end
+      end
+    end
+
+    context 'when entry config value is array of strings and arrays of strings' do
+      let(:config) { ['ls', ['pwd', 'echo 1']] }
+
+      describe '#value' do
+        it 'returns array of strings' do
+          expect(entry.value).to eq ['ls', 'pwd', 'echo 1']
+        end
+      end
+
+      describe '#errors' do
+        it 'does not append errors' do
+          expect(entry.errors).to be_empty
+        end
+      end
+
+      describe '#valid?' do
+        it 'is valid' do
+          expect(entry).to be_valid
+        end
+      end
+    end
+
     context 'when entry value is not correct' do
       let(:config) { 'ls' }
 
       describe '#errors' do
         it 'saves errors' do
           expect(entry.errors)
-            .to include 'script config should be an array of strings'
+            .to include 'script config should be an array of strings and arrays of strings'
         end
       end
 

spec/lib/gitlab/ci/yaml_processor_spec.rb

@@ -360,6 +360,19 @@ module Gitlab
               expect(subject[:options][:before_script]).to eq(["local script"])
             end
           end
+
+          context 'when script is array of arrays of strings' do
+            let(:config) do
+              {
+                before_script: [["global script", "echo 1"], ["ls"], "pwd"],
+                test: { script: ["script"] }
+              }
+            end
+
+            it "return commands with scripts concencaced" do
+              expect(subject[:options][:before_script]).to eq(["global script", "echo 1", "ls", "pwd"])
+            end
+          end
         end
 
         describe "script" do
@@ -427,6 +440,19 @@ module Gitlab
               expect(subject[:options][:after_script]).to eq(["local after_script"])
             end
           end
+
+          context 'when script is array of arrays of strings' do
+            let(:config) do
+              {
+                after_script: [["global script", "echo 1"], ["ls"], "pwd"],
+                test: { script: ["script"] }
+              }
+            end
+
+            it "return commands with scripts concencaced" do
+              expect(subject[:options][:after_script]).to eq(["global script", "echo 1", "ls", "pwd"])
+            end
+          end
         end
       end