Fix: MSH offset on array getters and setters

lib/segments/msh.rb

@@ -28,4 +28,14 @@ class HL7::Message::Segment::MSH < HL7::Message::Segment
   add_field :receiving_responsible_org
   add_field :sending_network_address
   add_field :receiving_network_address
+
+  # NOTE: MSH-1 has a special behaviour and is not included in the HL7 format, hence causing an offset to happen in the fields order
+  # This overriding of the following getter and setter ensure the order of the fields is respected
+  def [](index)
+    @elements[index - 1]
+  end
+
+  def []=(index, value)
+    @elements[index - 1] = value.to_s
+  end
 end

spec/msh_segment_spec.rb

@@ -3,27 +3,102 @@
 require "spec_helper"
 
 describe HL7::Message::Segment::MSH do
-  context "general" do
-    before :all do
-      @base = "MSH|^~\\&||ABCHS||AUSDHSV|20070101112951||ADT^A04^ADT_A01|12334456778890|P|2.5|||NE|NE|AU|ASCII|ENGLISH|||AN ORG|||RECNET.ORG"
+  describe "segment parsing" do
+    let(:segment_string) do
+      "MSH|^~\\&||ABCHS||AUSDHSV|20070101112951||ADT^A04^ADT_A01|12334456778890|P|2.5|||NE|NE|AU|ASCII|ENGLISH|||AN ORG|||RECNET.ORG"
     end
+    let(:filled_msh) { HL7::Message::Segment::MSH.new(segment_string) }
 
-    it "allows access to an MSH segment" do
-      msh = HL7::Message::Segment::MSH.new @base
-      msh.enc_chars = '^~\\&'
-      expect(msh.version_id).to eq "2.5"
-      expect(msh.country_code).to eq "AU"
-      expect(msh.charset).to eq "ASCII"
-      expect(msh.sending_responsible_org).to eq "AN ORG"
-      expect(msh.receiving_network_address).to eq "RECNET.ORG"
+    it "allows access to an MSH segment's attributes by their getters" do
+      expect(filled_msh.enc_chars).to eq("^~\\&")
+      expect(filled_msh.sending_app).to eq("")
+      expect(filled_msh.sending_facility).to eq("ABCHS")
+      expect(filled_msh.recv_app).to eq("")
+      expect(filled_msh.recv_facility).to eq("AUSDHSV")
+      expect(filled_msh.time).to eq("20070101112951")
+      expect(filled_msh.security).to eq("")
+      expect(filled_msh.message_type).to eq("ADT^A04^ADT_A01")
+      expect(filled_msh.message_control_id).to eq("12334456778890")
+      expect(filled_msh.processing_id).to eq("P")
+      expect(filled_msh.version_id).to eq("2.5")
+      expect(filled_msh.seq).to eq("")
+      expect(filled_msh.continue_ptr).to eq("")
+      expect(filled_msh.accept_ack_type).to eq("NE")
+      expect(filled_msh.app_ack_type).to eq("NE")
+      expect(filled_msh.country_code).to eq("AU")
+      expect(filled_msh.charset).to eq("ASCII")
+      expect(filled_msh.principal_language_of_message).to eq("ENGLISH")
+      expect(filled_msh.alternate_character_set_handling_scheme).to eq("")
+      expect(filled_msh.message_profile_identifier).to eq("")
+      expect(filled_msh.sending_responsible_org).to eq("AN ORG")
+      expect(filled_msh.receiving_responsible_org).to eq("")
+      expect(filled_msh.sending_network_address).to eq("")
+      expect(filled_msh.receiving_network_address).to eq("RECNET.ORG")
     end
 
-    it "allows creation of an MSH segment" do
-      msh = HL7::Message::Segment::MSH.new
-      msh.sending_facility = "A Facility"
-      expect(msh.sending_facility).to eq "A Facility"
-      msh.time = DateTime.iso8601("20010203T040506")
-      expect(msh.time).to eq "20010203040506"
+    it "allows access to an MSH segment's attributes by their index" do
+      expect(filled_msh[2]).to eq("^~\\&")
+      expect(filled_msh[3]).to eq("")
+      expect(filled_msh[4]).to eq("ABCHS")
+      expect(filled_msh[5]).to eq("")
+      expect(filled_msh[6]).to eq("AUSDHSV")
+      expect(filled_msh[7]).to eq("20070101112951")
+      expect(filled_msh[8]).to eq("")
+      expect(filled_msh[9]).to eq("ADT^A04^ADT_A01")
+      expect(filled_msh[10]).to eq("12334456778890")
+      expect(filled_msh[11]).to eq("P")
+      expect(filled_msh[12]).to eq("2.5")
+      expect(filled_msh[13]).to eq("")
+      expect(filled_msh[14]).to eq("")
+      expect(filled_msh[15]).to eq("NE")
+      expect(filled_msh[16]).to eq("NE")
+      expect(filled_msh[17]).to eq("AU")
+      expect(filled_msh[18]).to eq("ASCII")
+      expect(filled_msh[19]).to eq("ENGLISH")
+      expect(filled_msh[20]).to eq("")
+      expect(filled_msh[21]).to eq("")
+      expect(filled_msh[22]).to eq("AN ORG")
+      expect(filled_msh[23]).to eq("")
+      expect(filled_msh[24]).to eq("")
+      expect(filled_msh[25]).to eq("RECNET.ORG")
+    end
+  end
+
+  describe "segment creation" do
+    let(:msh) { HL7::Message::Segment::MSH.new }
+    let(:expected_msh_string) do
+      "MSH|^~\\&||ABCHS||AUSDHSV|20070101112951||ADT^A04^ADT_A01|12334456778890|P|2.5|||NE|NE|AU|ASCII|ENGLISH|||AN ORG|||RECNET.ORG"
+    end
+
+    before do
+      msh.enc_chars = "^~\\&"
+      msh.sending_app = ""
+      msh.sending_facility = "ABCHS"
+      msh.recv_app = ""
+      msh.recv_facility = "AUSDHSV"
+      msh.time = "20070101112951"
+      msh.security = ""
+      msh.message_type = "ADT^A04^ADT_A01"
+      msh.message_control_id = "12334456778890"
+      msh.processing_id = "P"
+      msh.version_id = "2.5"
+      msh.seq = ""
+      msh.continue_ptr = ""
+      msh.accept_ack_type = "NE"
+      msh.app_ack_type = "NE"
+      msh.country_code = "AU"
+      msh.charset = "ASCII"
+      msh.principal_language_of_message = "ENGLISH"
+      msh.alternate_character_set_handling_scheme = ""
+      msh.message_profile_identifier = ""
+      msh.sending_responsible_org = "AN ORG"
+      msh.receiving_responsible_org = ""
+      msh.sending_network_address = ""
+      msh.receiving_network_address = "RECNET.ORG"
+    end
+
+    it "serializes an MSH segment" do
+      expect(msh.to_s).to eq(expected_msh_string)
     end
   end
 end