Move configurations register to Y2Network::Config

* It was needed by Lan and LanItems, but the latter
  depended on the former.

src/lib/y2network/config.rb

@@ -49,6 +49,34 @@ def from(source, opts = {})
         reader = ConfigReader.for(source, opts)
         reader.config
       end
+
+      # Adds the configuration to the register
+      #
+      # @param id     [Symbol] Configuration ID
+      # @param config [Y2Network::Config] Network configuration
+      def add(id, config)
+        configs[id] = config
+      end
+
+      # Finds the configuration in the register
+      #
+      # @param id [Symbol] Configuration ID
+      # @return [Config,nil] Configuration with the given ID or nil if not found
+      def find(id)
+        configs[id]
+      end
+
+      # Resets the configuration register
+      def reset
+        configs.clear
+      end
+
+    private
+
+      # Configuration register
+      def configs
+        @configs ||= {}
+      end
     end
 
     # Constructor

src/modules/Lan.rb

@@ -974,20 +974,20 @@ def dhcp_ntp_servers
     # @param id [Symbol] Network configuration ID
     # @return [Y2Network::Config,nil] Network configuration with the given ID or nil if not found
     def find_config(id)
-      configs[id]
+      Y2Network::Config.find(id)
     end
 
     # Adds the configuration
     #
     # @param id     [Symbol] Configuration ID
     # @param config [Y2Network::Config] Network configuration
     def add_config(id, config)
-      configs[id] = config
+      Y2Network::Config.add(id, config)
     end
 
     # Clears the network configurations list
     def clear_configs
-      configs.clear
+      Y2Network::Config.reset
     end
 
     # Returns the system configuration

test/lan_test.rb

@@ -12,6 +12,10 @@
   subject { Yast::Lan }
   let(:system_config) { instance_double(Y2Network::Config, "System") }
 
+  before do
+    Yast::Lan.clear_configs
+  end
+
   describe "#Packages" do
     before(:each) do
       allow(Yast::NetworkService)
@@ -178,7 +182,6 @@ def expect_modification_succeedes(modname, method)
     let(:routing) { Y2Network::Routing.new(tables: []) }
 
     it "returns true when Routing module was modified" do
-      Yast::Lan.clear_configs
       Yast::Lan.add_config(:system, config)
       yast_config = config.copy
       yast_config.routing.forward_ipv4 = !config.routing.forward_ipv4

test/y2network/config_test.rb

@@ -24,6 +24,10 @@
 require "y2network/config_writer/sysconfig"
 
 describe Y2Network::Config do
+  before do
+    Y2Network::Config.reset
+  end
+
   subject(:config) do
     described_class.new(interfaces: [eth0], routing: routing, source: :sysconfig)
   end
@@ -53,6 +57,30 @@
     end
   end
 
+  describe ".add" do
+    it "adds the configuration to the register" do
+      expect { Y2Network::Config.add(:yast, config) }
+        .to change { Y2Network::Config.find(:yast) }
+        .from(nil).to(config)
+    end
+  end
+
+  describe ".find" do
+    before do
+      Y2Network::Config.add(:yast, config)
+    end
+
+    it "returns the registered config with the given ID" do
+      expect(Y2Network::Config.find(:yast)).to eq(config)
+    end
+
+    context "when a configuration with the given ID does not exist" do
+      it "returns nil" do
+        expect(Y2Network::Config.find(:test)).to be_nil
+      end
+    end
+  end
+
   describe "#routes" do
     it "returns routes from all tables" do
       expect(config.routing.routes).to eq([route1, route2])