Extracts cache initialization to collection class

lib/gitlab/ci/build/cache.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module Ci
+    module Build
+      class Cache
+        include ::Gitlab::Utils::StrongMemoize
+
+        def initialize(cache, pipeline)
+          if multiple_cache_per_job?
+            cache = Array.wrap(cache)
+            @cache = cache.map do |cache|
+              Gitlab::Ci::Pipeline::Seed::Build::Cache
+              .new(pipeline, cache)
+            end
+          else
+            @cache = Gitlab::Ci::Pipeline::Seed::Build::Cache
+              .new(pipeline, cache)
+          end
+        end
+
+        def cache_attributes
+          strong_memoize(:cache_attributes) do
+            if multiple_cache_per_job?
+              if @cache.empty?
+                {}
+              else
+                { options: { cache: @cache.map(&:attributes) } }
+              end
+            else
+              @cache.build_attributes
+            end
+          end
+        end
+
+        private
+
+        def multiple_cache_per_job?
+          strong_memoize(:multiple_cache_per_job) do
+            ::Gitlab::Ci::Features.multiple_cache_per_job?
+          end
+        end
+      end
+    end
+  end
+end

lib/gitlab/ci/pipeline/seed/build.rb

@@ -28,16 +28,8 @@ module Gitlab
               .fabricate(attributes.delete(:except))
             @rules = Gitlab::Ci::Build::Rules
               .new(attributes.delete(:rules), default_when: 'on_success')
-
-            if multiple_cache_per_job?
-              cache = Array.wrap(attributes.delete(:cache))
-              @cache = cache.map do |cache|
-                Seed::Build::Cache.new(pipeline, cache)
-              end
-            else
-              @cache = Seed::Build::Cache
-                .new(pipeline, attributes.delete(:cache))
-            end
+            @cache = Gitlab::Ci::Build::Cache
+              .new(attributes.delete(:cache), pipeline)
           end
 
           def name
@@ -69,7 +61,7 @@ module Gitlab
               .deep_merge(pipeline_attributes)
               .deep_merge(rules_attributes)
               .deep_merge(allow_failure_criteria_attributes)
-              .deep_merge(cache_attributes)
+              .deep_merge(@cache.cache_attributes)
           end
 
           def bridge?
@@ -203,26 +195,6 @@ module Gitlab
             end
           end
 
-          def cache_attributes
-            strong_memoize(:cache_attributes) do
-              if multiple_cache_per_job?
-                if @cache.empty?
-                  {}
-                else
-                  { options: { cache: @cache.map(&:attributes) } }
-                end
-              else
-                @cache.build_attributes
-              end
-            end
-          end
-
-          def multiple_cache_per_job?
-            strong_memoize(:multiple_cache_per_job) do
-              ::Gitlab::Ci::Features.multiple_cache_per_job?
-            end
-          end
-
           # If a job uses `allow_failure:exit_codes` and `rules:allow_failure`
           # we need to prevent the exit codes from being persisted because they
           # would break the behavior defined by `rules:allow_failure`.

spec/lib/gitlab/ci/build/cache_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::Ci::Build::Cache do
+  describe '.initialize' do
+    context 'when the multiple cache feature flag is disabled' do
+      before do
+        stub_feature_flags(multiple_cache_per_job: false)
+      end
+
+      it 'instantiates a cache seed' do
+        cache_config = { key: 'key-a' }
+        pipeline = double(::Ci::Pipeline)
+        cache_seed = double(Gitlab::Ci::Pipeline::Seed::Build::Cache)
+        allow(Gitlab::Ci::Pipeline::Seed::Build::Cache).to receive(:new).and_return(cache_seed)
+
+        cache = described_class.new(cache_config, pipeline)
+
+        expect(Gitlab::Ci::Pipeline::Seed::Build::Cache).to have_received(:new).with(pipeline, cache_config)
+        expect(cache.instance_variable_get(:@cache)).to eq(cache_seed)
+      end
+    end
+
+    context 'when the multiple cache feature flag is enabled' do
+      context 'when the cache is an array' do
+        it 'instantiates an array of cache seeds' do
+          cache_config = [{ key: 'key-a' }, { key: 'key-b' }]
+          pipeline = double(::Ci::Pipeline)
+          cache_seed_a = double(Gitlab::Ci::Pipeline::Seed::Build::Cache)
+          cache_seed_b = double(Gitlab::Ci::Pipeline::Seed::Build::Cache)
+          allow(Gitlab::Ci::Pipeline::Seed::Build::Cache).to receive(:new).and_return(cache_seed_a, cache_seed_b)
+
+          cache = described_class.new(cache_config, pipeline)
+
+          expect(Gitlab::Ci::Pipeline::Seed::Build::Cache).to have_received(:new).with(pipeline, { key: 'key-a' })
+          expect(Gitlab::Ci::Pipeline::Seed::Build::Cache).to have_received(:new).with(pipeline, { key: 'key-b' })
+          expect(cache.instance_variable_get(:@cache)).to eq([cache_seed_a, cache_seed_b])
+        end
+      end
+
+      context 'when the cache is a hash' do
+        it 'instantiates a cache seed' do
+          cache_config = { key: 'key-a' }
+          pipeline = double(::Ci::Pipeline)
+          cache_seed = double(Gitlab::Ci::Pipeline::Seed::Build::Cache)
+          allow(Gitlab::Ci::Pipeline::Seed::Build::Cache).to receive(:new).and_return(cache_seed)
+
+          cache = described_class.new(cache_config, pipeline)
+
+          expect(Gitlab::Ci::Pipeline::Seed::Build::Cache).to have_received(:new).with(pipeline, cache_config)
+          expect(cache.instance_variable_get(:@cache)).to eq([cache_seed])
+        end
+      end
+    end
+  end
+
+  describe '#cache_attributes' do
+    context 'when the multiple cache feature flag is disabled' do
+      before do
+        stub_feature_flags(multiple_cache_per_job: false)
+      end
+
+      it "returns the cache seed's build attributes" do
+        cache_config = { key: 'key-a' }
+        pipeline = double(::Ci::Pipeline)
+        cache = described_class.new(cache_config, pipeline)
+
+        attributes = cache.cache_attributes
+
+        expect(attributes).to eq({
+          options: { cache: { key: 'key-a' } }
+        })
+      end
+    end
+
+    context 'when the multiple cache feature flag is enabled' do
+      context 'when there are no caches' do
+        it 'returns an empty hash' do
+          cache_config = []
+          pipeline = double(::Ci::Pipeline)
+          cache = described_class.new(cache_config, pipeline)
+
+          attributes = cache.cache_attributes
+
+          expect(attributes).to eq({})
+        end
+      end
+
+      context 'when there are caches' do
+        it 'returns the structured attributes for the caches' do
+          cache_config = [{ key: 'key-a' }, { key: 'key-b' }]
+          pipeline = double(::Ci::Pipeline)
+          cache = described_class.new(cache_config, pipeline)
+
+          attributes = cache.cache_attributes
+
+          expect(attributes).to eq({
+            options: { cache: cache_config }
+          })
+        end
+      end
+    end
+  end
+end