Add test generator for rna transcription exercise

exercises/rna-transcription/Example.cs

@@ -8,8 +8,13 @@ public class Complement
             { 'G', 'C' }, { 'C', 'G' }, { 'T', 'A' }, { 'A', 'U' }
         };
 
-    public static string OfDna(string nucleotide)
+    public static string ToRna(string nucleotide)
     {
+        if (nucleotide.Any(x => !DnaToRna.ContainsKey(x)))
+        {
+            return null;
+        }
+
         return string.Concat(nucleotide.Select(x => DnaToRna[x]));
     }
 }

exercises/rna-transcription/RnaTranscription.cs

@@ -1,8 +1,8 @@
 using System;
 
-public static class Complement
+public static class RnaTranscription
 {
-    public static string OfDna(string nucleotide)
+    public static string ToRna(string nucleotide)
     {
         throw new NotImplementedException("You need to implement this function.");
     }

exercises/rna-transcription/RnaTranscriptionTest.cs

@@ -1,34 +1,54 @@
+// This file was auto-generated based on version 1.0.1 of the canonical data.
+
 using Xunit;
 
-public class ComplementTest
+public class RnaTranscriptionTest
 {
     [Fact]
     public void Rna_complement_of_cytosine_is_guanine()
     {
-        Assert.Equal("G", Complement.OfDna("C"));
+        Assert.Equal("G", RnaTranscription.ToRna("C"));
     }
 
     [Fact(Skip = "Remove to run test")]
     public void Rna_complement_of_guanine_is_cytosine()
     {
-        Assert.Equal("C", Complement.OfDna("G"));
+        Assert.Equal("C", RnaTranscription.ToRna("G"));
     }
 
     [Fact(Skip = "Remove to run test")]
     public void Rna_complement_of_thymine_is_adenine()
     {
-        Assert.Equal("A", Complement.OfDna("T"));
+        Assert.Equal("A", RnaTranscription.ToRna("T"));
     }
 
     [Fact(Skip = "Remove to run test")]
     public void Rna_complement_of_adenine_is_uracil()
     {
-        Assert.Equal("U", Complement.OfDna("A"));
+        Assert.Equal("U", RnaTranscription.ToRna("A"));
     }
 
     [Fact(Skip = "Remove to run test")]
     public void Rna_complement()
     {
-        Assert.Equal("UGCACCAGAAUU", Complement.OfDna("ACGTGGTCTTAA"));
+        Assert.Equal("UGCACCAGAAUU", RnaTranscription.ToRna("ACGTGGTCTTAA"));
+    }
+
+    [Fact(Skip = "Remove to run test")]
+    public void Correctly_handles_invalid_input_rna_instead_of_dna_()
+    {
+        Assert.Equal(null, RnaTranscription.ToRna("U"));
+    }
+
+    [Fact(Skip = "Remove to run test")]
+    public void Correctly_handles_completely_invalid_dna_input()
+    {
+        Assert.Equal(null, RnaTranscription.ToRna("XXX"));
+    }
+
+    [Fact(Skip = "Remove to run test")]
+    public void Correctly_handles_partially_invalid_dna_input()
+    {
+        Assert.Equal(null, RnaTranscription.ToRna("ACGTXXXCTTAA"));
     }
 }

generators/Exercises/RnaTranscription.cs

@@ -0,0 +1,16 @@
+using Generators.Input;
+using Generators.Output;
+
+namespace Generators.Exercises
+{
+    public class RnaTranscription : Exercise
+    {
+        protected override void UpdateCanonicalData(CanonicalData canonicalData)
+        {
+            foreach (var canonicalDataCase in CanonicalData.Cases)
+            {
+                canonicalDataCase.Expected = canonicalDataCase.Expected ?? new UnescapedValue("null");
+            }
+        }
+    }
+}