Use latest default branch SHA to get external local files

This commit makes it explicit that we want to use latest SHA on a
default branch to get external CI/CD files, _via_ `include` directive.

ee/lib/ee/gitlab/ci/config.rb

@@ -27,7 +27,7 @@ module EE
         end
 
         def process_external_files(config, project, opts)
-          sha = opts.fetch(:sha, project.repository.commit.sha)
+          sha = opts.fetch(:sha, project.repository.root_ref_sha)
           ::Gitlab::Ci::External::Processor.new(config, project, sha).perform
         end
       end

ee/spec/lib/ee/gitlab/ci/config_spec.rb

 require 'spec_helper'
 
 describe EE::Gitlab::Ci::Config do
+  let(:config_class) { ::Gitlab::Ci::Config }
   let(:project) { create(:project, :repository) }
   let(:remote_location) { 'https://gitlab.com/gitlab-org/gitlab-ce/blob/1234/.gitlab-ci-1.yml' }
+  let(:local_location) { 'ee/spec/fixtures/gitlab/ci/external_files/.gitlab-ci-template-1.yml' }
+
+  let(:remote_file_content) do
+    <<~HEREDOC
+      variables:
+        AUTO_DEVOPS_DOMAIN: domain.example.com
+        POSTGRES_USER: user
+        POSTGRES_PASSWORD: testing-password
+        POSTGRES_ENABLED: "true"
+        POSTGRES_DB: $CI_ENVIRONMENT_SLUG
+    HEREDOC
+  end
+
+  let(:local_file_content) do
+    File.read(Rails.root.join(local_location))
+  end
+
   let(:gitlab_ci_yml) do
     <<~HEREDOC
       include:
-      - /ee/spec/fixtures/gitlab/ci/external_files/.gitlab-ci-template-1.yml
+        - #{local_location}
         - #{remote_location}
 
       image: ruby:2.2
@@ -14,12 +32,21 @@ describe EE::Gitlab::Ci::Config do
   end
 
   let(:config) do
-    ::Gitlab::Ci::Config.new(gitlab_ci_yml, project: project, sha: '12345')
+    config_class.new(gitlab_ci_yml, project: project, sha: '12345')
+  end
+
+  before do
+    WebMock.stub_request(:get, remote_location)
+      .to_return(body: remote_file_content)
+
+    allow(project.repository)
+      .to receive(:blob_data_at).and_return(local_file_content)
   end
 
   context 'when the project does not have a valid license' do
     before do
-      allow(project).to receive(:feature_available?).with(:external_files_in_gitlab_ci).and_return(false)
+      allow(project).to receive(:feature_available?)
+        .with(:external_files_in_gitlab_ci).and_return(false)
     end
 
     it "should raise a ValidationError" do
@@ -31,26 +58,13 @@ describe EE::Gitlab::Ci::Config do
   end
 
   context 'when the project has a valid license' do
-    let(:remote_file_content) do
-      <<~HEREDOC
-      variables:
-        AUTO_DEVOPS_DOMAIN: domain.example.com
-        POSTGRES_USER: user
-        POSTGRES_PASSWORD: testing-password
-        POSTGRES_ENABLED: "true"
-        POSTGRES_DB: $CI_ENVIRONMENT_SLUG
-      HEREDOC
-    end
-    let(:local_file_content) {  File.read(Rails.root.join('ee/spec/fixtures/gitlab/ci/external_files/.gitlab-ci-template-1.yml')) }
-
     before do
-      allow(project).to receive(:feature_available?).with(:external_files_in_gitlab_ci).and_return(true)
+      allow(project).to receive(:feature_available?)
+        .with(:external_files_in_gitlab_ci).and_return(true)
     end
 
     context "when gitlab_ci_yml has valid 'include' defined" do
       before do
-        allow_any_instance_of(Gitlab::Ci::External::File::Local).to receive(:fetch_local_content).and_return(local_file_content)
-        WebMock.stub_request(:get, remote_location).to_return(body: remote_file_content)
       end
 
       it 'should return a composed hash' do
@@ -94,19 +108,20 @@ describe EE::Gitlab::Ci::Config do
     end
 
     describe 'external file version' do
-      context 'when external file SHA is defined' do
+      context 'when external local file SHA is defined' do
         it 'is using a defined value' do
-          expect(project.repository).to receive(:find_commit).with('eeff1122')
+          expect(project.repository).to receive(:blob_data_at)
+            .with('eeff1122', local_location)
 
-          config.new(gitlab_ci_yml, project: project, sha: 'eeff1122')
+          config_class.new(gitlab_ci_yml, project: project, sha: 'eeff1122')
         end
       end
 
-      context 'when external file SHA is not defined' do
+      context 'when external local file SHA is not defined' do
         it 'is using latest SHA on the default branch' do
           expect(project.repository).to receive(:root_ref_sha)
 
-          config.new(gitlab_ci_yml, project: project)
+          config_class.new(gitlab_ci_yml, project: project)
         end
       end
     end
@@ -128,7 +143,6 @@ describe EE::Gitlab::Ci::Config do
       end
 
       it 'should take precedence' do
-        WebMock.stub_request(:get, remote_location).to_return(body: remote_file_content)
         expect(config.to_hash).to eq({ image: 'ruby:2.2' })
       end
     end
@@ -154,7 +168,6 @@ describe EE::Gitlab::Ci::Config do
       end
 
       it 'should merge the variables dictionaries' do
-        WebMock.stub_request(:get, remote_location).to_return(body: remote_file_content)
         expect(config.to_hash).to eq({ variables: { A: 'alpha', B: 'beta', C: 'gamma', D: 'delta' } })
       end
     end
@@ -181,7 +194,6 @@ describe EE::Gitlab::Ci::Config do
       end
 
       it 'later declarations should take precedence' do
-        WebMock.stub_request(:get, remote_location).to_return(body: remote_file_content)
         expect(config.to_hash).to eq({ variables: { A: 'alpha', B: 'beta', C: 'gamma', D: 'delta' } })
       end
     end
@@ -207,7 +219,6 @@ describe EE::Gitlab::Ci::Config do
       end
 
       it 'merges the jobs' do
-        WebMock.stub_request(:get, remote_location).to_return(body: remote_file_content)
         expect(config.to_hash).to eq({
           job1: {
             script: ["echo 'hello from remote file'"],
@@ -233,7 +244,6 @@ describe EE::Gitlab::Ci::Config do
         end
 
         it 'uses the script from the gitlab_ci.yml' do
-          WebMock.stub_request(:get, remote_location).to_return(body: remote_file_content)
           expect(config.to_hash).to eq({
             job1: {
               script: ["echo 'hello from main file'"],