Add test for current metadata_download_helper behavior

Author: mokagio

spec/metadata_download_helper_spec.rb

@@ -0,0 +1,42 @@
+require 'spec_helper'
+
+describe Fastlane::Helper::MetadataDownloader do
+  describe 'downloading from GlotPress' do
+    context 'when GlotPress returs a 429 code' do
+      it 'automatically retries' do
+        in_tmp_dir do |tmp_dir|
+          metadata_downaloder = described_class.new(
+            tmp_dir,
+            { key: { desc: 'target-file-name.txt' } },
+            true
+          )
+
+          fake_url = 'https://test.com'
+
+          count = 0
+          stub_request(:get, fake_url).to_return do
+            count += 1
+            if count == 1
+              { status: 429, body: 'Too Many Requests' }
+            else
+              { status: 200, body: 'OK' }
+            end
+          end
+
+          expect(Fastlane::UI).to receive(:message)
+            .with(/Received 429 for `en-AU`. Auto retrying in 20 seconds.../)
+
+          expect(Fastlane::UI).to receive(:message)
+            .with(/No translation available for en-AU/)
+
+          expect(Fastlane::UI).to receive(:success)
+            .with(/Successfully downloaded `en-AU`./)
+
+          metadata_downaloder.download('en-AU', fake_url, false)
+
+          expect(count).to eq(2)
+        end
+      end
+    end
+  end
+end