@@ -155,6 +155,7 @@ public void Should_Throw_If_Process_Was_Not_Started()
             [InlineData(-1, "NUnit3: Invalid argument (exit code -1).")]
             [InlineData(-2, "NUnit3: Invalid assembly (exit code -2).")]
             [InlineData(-4, "NUnit3: Invalid test fixture (exit code -4).")]
+            [InlineData(-5, "NUnit3: Unload error (exit code -5).")]
             [InlineData(-100, "NUnit3: Unexpected error (exit code -100).")]
             [InlineData(-10, "NUnit3: Unrecognised error (exit code -10).")]
             public void Should_Throw_If_Process_Has_A_Non_Zero_Exit_Code(int exitCode, string expectedMessage)
@@ -215,6 +216,7 @@ public void Should_Set_Commandline_Switches()
                 fixture.Settings.Seed = 6;
                 fixture.Settings.Workers = 7;
                 fixture.Settings.StopOnError = true;
+                fixture.Settings.SkipNonTestAssemblies = true;
                 fixture.Settings.Work = "out";
                 fixture.Settings.OutputFile = "stdout.txt";
                 #pragma warning disable 0618
@@ -255,7 +257,7 @@ public void Should_Set_Commandline_Switches()
                 // Then
                 Assert.Equal("\"/Working/Test1.dll\" --test=Test1,Test2 \"--testlist=/Working/Testlist.txt\" " +
                         "--where \"cat==Data\" --timeout=5 --seed=6 --workers=7 " +
-                        "--stoponerror \"--work=/Working/out\" \"--out=/Working/stdout.txt\" " +
+                        "--stoponerror --skipnontestassemblies \"--work=/Working/out\" \"--out=/Working/stdout.txt\" " +
                         "\"--err=/Working/stderr.txt\" --full " +
                         "\"--result=/Working/NewTestResult.xml;format=nunit2;transform=/Working/nunit2.xslt\" " +
                         "\"--result=/Working/NewTestResult2.xml;format=nunit3\" " +
 
@@ -13,7 +13,7 @@
 namespace Cake.Common.Tools.NUnit
 {
     /// <summary>
-    /// The NUnit unit test runner.
+    /// The NUnit3 unit test runner.
     /// </summary>
     public sealed class NUnit3Runner : Tool<NUnit3Settings>
     {
@@ -99,6 +99,11 @@ private ProcessArgumentBuilder GetArguments(IEnumerable<FilePath> assemblyPaths,
                 builder.Append("--stoponerror");
             }
 
+            if (settings.SkipNonTestAssemblies)
+            {
+                builder.Append("--skipnontestassemblies");
+            }
+
             if (settings.Work != null)
             {
                 builder.AppendQuoted(string.Format(CultureInfo.InvariantCulture, "--work={0}", settings.Work.MakeAbsolute(_environment).FullPath));
@@ -256,7 +261,7 @@ protected override IEnumerable<string> GetToolExecutableNames()
         }
 
         /// <summary>
-        /// Customized exit code handling.
+        /// Customized Nunit3 exit code handling.
         /// Throws <see cref="CakeException"/> on non-zero exit code
         /// </summary>
         /// <param name="exitCode">The process exit code</param>
@@ -279,6 +284,9 @@ protected override void ProcessExitCode(int exitCode)
                     case -4:
                         error = "Invalid test fixture";
                         break;
+                    case -5:
+                        error = "Unload error";
+                        break;
                     case -100:
                         error = "Unexpected error";
                         break;
 
@@ -80,6 +80,16 @@ public sealed class NUnit3Settings : ToolSettings
         /// </value>
         public bool StopOnError { get; set; }
 
+        /// <summary>
+        /// Gets or sets a value indicating whether execution of the test run should
+        /// skip any non-test assemblies specified, without error.
+        /// </summary>
+        /// <value>
+        /// <c>true</c> if execution of the test run should skip any non-test assemblies specified, without error;
+        /// otherwise, <c>false</c>.
+        /// </value>
+        public bool SkipNonTestAssemblies { get; set; }
+
         /// <summary>
         /// Gets or sets the directory to use for output files. If
         /// not specified, defaults to the current directory.
 
@@ -188,7 +188,7 @@ protected override IEnumerable<string> GetToolExecutableNames()
         }
 
         /// <summary>
-        /// Customized exit code handling.
+        /// Customized Nunit exit code handling.
         /// Throws <see cref="CakeException"/> on non-zero exit code
         /// </summary>
         /// <param name="exitCode">The process exit code</param>
Original file line number	Diff line number	Diff line change
`@@ -188,7 +188,7 @@ protected override IEnumerable<string> GetToolExecutableNames()`
`188`	`188`	`}`
`189`	`189`
`190`	`190`	`/// <summary>`
`191`		`- /// Customized exit code handling.`
	`191`	`+ /// Customized Nunit exit code handling.`
`192`	`192`	`/// Throws <see cref="CakeException"/> on non-zero exit code`
`193`	`193`	`/// </summary>`
`194`	`194`	`/// <param name="exitCode">The process exit code</param>`