Fix deserializing yaml variables in imported projects

lib/gitlab/serializer/ci/variables.rb

@@ -13,8 +13,9 @@ module Gitlab
           object = YAML.safe_load(string, [Symbol])
 
           object.map do |variable|
+            variable.symbolize_keys.tap do |variable|
               variable[:key] = variable[:key].to_s
-            variable
+            end
           end
         end
 

spec/lib/gitlab/serializer/ci/variables_spec.rb

-require 'spec_helper'
+require 'fast_spec_helper'
 
 describe Gitlab::Serializer::Ci::Variables do
   subject do
@@ -6,11 +6,11 @@ describe Gitlab::Serializer::Ci::Variables do
   end
 
   let(:object) do
-    [{ key: :key, value: 'value', public: true },
+    [{ 'key' => :key, 'value' => 'value', 'public' => true },
      { key: 'wee', value: 1, public: false }]
   end
 
-  it 'converts keys into strings' do
+  it 'converts keys into strings and symbolizes hash' do
     is_expected.to eq([
       { key: 'key', value: 'value', public: true },
       { key: 'wee', value: 1, public: false }

spec/models/ci/build_spec.rb

@@ -2269,6 +2269,34 @@ describe Ci::Build do
     end
   end
 
+  describe '#yaml_variables' do
+    before do
+      build.update_attribute(:yaml_variables, variables)
+    end
+
+    context 'when serialized valu is a symbolized hash' do
+      let(:variables) do
+        [{ key: :VARIABLE, value: 'my value 1' }]
+      end
+
+      it 'keeps symbolizes keys and stringifies variables names' do
+        expect(build.yaml_variables)
+          .to eq [{ key: 'VARIABLE', value: 'my value 1' }]
+      end
+    end
+
+    context 'when serialized value is a hash with string keys' do
+      let(:variables) do
+        [{'key' => :VARIABLE, 'value' => 'my value 2' }]
+      end
+
+      it 'symblizes variables hash' do
+        expect(build.yaml_variables)
+          .to eq [{ key: 'VARIABLE', value: 'my value 2' }]
+      end
+    end
+  end
+
   describe 'state transition: any => [:pending]' do
     let(:build) { create(:ci_build, :created) }