diff --git a/spec/OneClickInstallWorkerFunctions_spec.rb b/spec/OneClickInstallWorkerFunctions_spec.rb
new file mode 100644
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+++ b/spec/OneClickInstallWorkerFunctions_spec.rb
@@ -0,0 +1,118 @@
+#! /usr/bin/env rspec
+
+# Copyright (c) [2021] SUSE LLC
+#
+# All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of version 2 of the GNU General Public License as published
+# by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, contact SUSE LLC.
+#
+# To contact SUSE LLC about this file by physical or electronic mail, you may
+# find current contact information at www.suse.com.
+
+require_relative "spec_helper"
+
+require "yast"
+
+Yast.import "OneClickInstallWorkerFunctions"
+
+describe Yast::OneClickInstallWorkerFunctions do
+
+  let(:urls) { %w[http://example.com/repo1 http://example.com/repo2 http://example.com/repo3] }
+
+  describe "#DeDupe" do
+    before do
+      allow(Yast::Pkg).to receive(:SourceStartCache).and_return([1])
+    end
+    context "when receives repository that is not subscribed on" do
+      it "does not filter the repository" do
+        allow(Yast::Pkg).to receive(:SourceGeneralData).and_return({})
+        allow(Yast::OneClickInstall).to receive(:GetRepositoryName).and_return("test-name")
+
+        expect(subject.DeDupe(urls)).to contain_exactly(urls[0], urls[1], urls[2])
+      end
+    end
+
+    context "when receives repository that is already subscribed on" do
+      it "removes repository if it is duplicated by 'url'" do
+        allow(Yast::Pkg).to receive(:SourceGeneralData).and_return("url" => urls[1])
+        allow(Yast::OneClickInstall).to receive(:GetRepositoryName).and_return("test-name")
+
+        expect(subject.DeDupe(urls)).to contain_exactly(urls[0], urls[2])
+      end
+      it "removes repository if it is duplicated by 'name'" do
+        allow(Yast::Pkg).to receive(:SourceGeneralData).and_return({ "name" => "oss" }, {}, {})
+        allow(Yast::OneClickInstall).to receive(:GetRepositoryName).and_return("oss")
+
+        expect(subject.DeDupe(urls)).to contain_exactly(urls[1], urls[2])
+      end
+      it "removes repository if it is duplicated by 'alias'" do
+        allow(Yast::Pkg).to receive(:SourceGeneralData).and_return({}, {}, "alias" => "oss")
+        allow(Yast::OneClickInstall).to receive(:GetRepositoryName).and_return("oss")
+
+        expect(subject.DeDupe(urls)).to contain_exactly(urls[0], urls[1])
+      end
+    end
+  end
+
+  describe '#AddRepositories' do
+    before do
+      allow(subject).to receive(:DeDupe).and_return(urls)
+    end
+    context "when metadata can be downloaded for all repositories" do
+      before do
+        allow(Yast::Pkg).to receive(:SourceRefreshNow).and_return(true)
+      end
+      it "successfully adds the repositories" do
+        expect(subject.AddRepositories(urls)).to be true
+      end
+    end
+
+    context "when metadata can NOT be downloaded" do
+      context "for all repositories" do
+        before do
+          allow(Yast::Pkg).to receive(:SourceRefreshNow).and_return(false)
+        end
+        it "does NOT add all the repositories" do
+          expect(subject.AddRepositories(urls)).to be false
+        end
+      end
+      context "for at least one repository" do
+        before do
+          allow(Yast::Pkg).to receive(:SourceRefreshNow).and_return(false, true, true)
+        end
+        it "does NOT add all the repositories" do
+          expect(subject.AddRepositories(urls)).to be false
+        end
+      end
+    end
+  end
+
+  describe '#RemoveAddedRepositories' do
+    context "when metadata cached on disk is removed" do
+      before do
+        allow(Yast::Pkg).to receive(:SourceDelete).and_return(true)
+      end
+      it "removes added repositories" do
+        expect(subject.RemoveAddedRepositories).to be true
+      end
+    end
+    context "when metadata cached on disk is NOT removed" do
+      before do
+        allow(Yast::Pkg).to receive(:SourceDelete).and_return(false)
+      end
+      it "does not remove added repositories" do
+        expect(subject.RemoveAddedRepositories).to be false
+      end
+    end
+  end
+end