Handling an exception that happens when dotnet run is invoked with a file that is not a valid project file. We catch that exception and re-throw it as a GracefulException.

src/dotnet/Properties/AssemblyInfo.cs

@@ -16,3 +16,4 @@ using System.Runtime.CompilerServices;
 [assembly: InternalsVisibleTo("dotnet-sln-list.Tests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100f33a29044fa9d740c9b3213a93e57c84b472c84e0b8a0e1ae48e67a9f8f6de9d5f7f3d52ac23e48ac51801f1dc950abe901da34d2a9e3baadb141a17c77ef3c565dd5ee5054b91cf63bb3c6ab83f72ab3aafe93d0fc3c2348b764fafb0b1c0733de51459aeab46580384bf9d74c4e28164b7cde247f891ba07891c9d872ad2bb")]
 [assembly: InternalsVisibleTo("dotnet-sln-remove.Tests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100f33a29044fa9d740c9b3213a93e57c84b472c84e0b8a0e1ae48e67a9f8f6de9d5f7f3d52ac23e48ac51801f1dc950abe901da34d2a9e3baadb141a17c77ef3c565dd5ee5054b91cf63bb3c6ab83f72ab3aafe93d0fc3c2348b764fafb0b1c0733de51459aeab46580384bf9d74c4e28164b7cde247f891ba07891c9d872ad2bb")]
 [assembly: InternalsVisibleTo("dotnet-msbuild.Tests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100f33a29044fa9d740c9b3213a93e57c84b472c84e0b8a0e1ae48e67a9f8f6de9d5f7f3d52ac23e48ac51801f1dc950abe901da34d2a9e3baadb141a17c77ef3c565dd5ee5054b91cf63bb3c6ab83f72ab3aafe93d0fc3c2348b764fafb0b1c0733de51459aeab46580384bf9d74c4e28164b7cde247f891ba07891c9d872ad2bb")]
+[assembly: InternalsVisibleTo("dotnet-run.Tests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100f33a29044fa9d740c9b3213a93e57c84b472c84e0b8a0e1ae48e67a9f8f6de9d5f7f3d52ac23e48ac51801f1dc950abe901da34d2a9e3baadb141a17c77ef3c565dd5ee5054b91cf63bb3c6ab83f72ab3aafe93d0fc3c2348b764fafb0b1c0733de51459aeab46580384bf9d74c4e28164b7cde247f891ba07891c9d872ad2bb")]

src/dotnet/commands/dotnet-run/LocalizableStrings.resx

@@ -196,4 +196,7 @@ The current {1} is '{2}'.</value>
     <value>An error was encountered when reading launchSettings.json.
 {0}</value>
   </data>
+  <data name="RunCommandSpecifiecFileIsNotAValidProject" xml:space="preserve">
+    <value>'{0}' is not a valid project file.</value>
+  </data>
 </root>

src/dotnet/commands/dotnet-run/RunCommand.cs

@@ -6,6 +6,7 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using Microsoft.Build.Evaluation;
+using Microsoft.Build.Exceptions;
 using Microsoft.DotNet.Cli.Utils;
 using Microsoft.DotNet.Tools;
 using Microsoft.DotNet.Tools.MSBuild;
@@ -39,17 +40,26 @@ namespace Microsoft.DotNet.Tools.Run
                 EnsureProjectIsBuilt();
             }
 
-            ICommand runCommand = GetRunCommand();
+            try
-            int launchSettingsApplicationResult = ApplyLaunchProfileSettingsIfNeeded(ref runCommand);
-
-            if (launchSettingsApplicationResult != 0)
             {
-                return launchSettingsApplicationResult;
+                ICommand runCommand = GetRunCommand();
-            }
+                int launchSettingsApplicationResult = ApplyLaunchProfileSettingsIfNeeded(ref runCommand);
 
-            return runCommand
+                if (launchSettingsApplicationResult != 0)
-                .Execute()
+                {
-                .ExitCode;
+                    return launchSettingsApplicationResult;
+                }
+
+                return runCommand
+                    .Execute()
+                    .ExitCode;
+            }
+            catch (InvalidProjectFileException e)
+            {
+                throw new GracefulException(
+                    string.Format(LocalizableStrings.RunCommandSpecifiecFileIsNotAValidProject, Project),
+                    e);
+            }
         }
 
         public RunCommand(string configuration,

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.cs.xlf

@@ -136,6 +136,11 @@ Aktuální {1} je {2}.</target>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.de.xlf

@@ -136,6 +136,11 @@ Ein ausführbares Projekt sollte ein ausführbares TFM (z.B. netcoreapp2.0) verw
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.es.xlf

@@ -136,6 +136,11 @@ El actual {1} es '{2}'.</target>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.fr.xlf

@@ -136,6 +136,11 @@ Le {1} actuel est '{2}'.</target>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.it.xlf

@@ -136,6 +136,11 @@ Il valore corrente di {1} è '{2}'.</target>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.ja.xlf

@@ -136,6 +136,11 @@ The current {1} is '{2}'.</source>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.ko.xlf

@@ -136,6 +136,11 @@ The current {1} is '{2}'.</source>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.pl.xlf

@@ -136,6 +136,11 @@ Bieżący element {1}: „{2}”.</target>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.pt-BR.xlf

@@ -136,6 +136,11 @@ O {1} atual é '{2}'.</target>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.ru.xlf

@@ -136,6 +136,11 @@ The current {1} is '{2}'.</source>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.tr.xlf

@@ -136,6 +136,11 @@ Geçerli {1}: '{2}'.</target>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.zh-Hans.xlf

@@ -136,6 +136,11 @@ The current {1} is '{2}'.</source>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/dotnet/commands/dotnet-run/xlf/LocalizableStrings.zh-Hant.xlf

@@ -136,6 +136,11 @@ The current {1} is '{2}'.</source>
 {0}</target>
         <note />
       </trans-unit>
+      <trans-unit id="RunCommandSpecifiecFileIsNotAValidProject">
+        <source>'{0}' is not a valid project file.</source>
+        <target state="new">'{0}' is not a valid project file.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

test/dotnet-run.Tests/GivenThatWeCanPassNonProjectFilesToDotnetRun.cs

@@ -0,0 +1,35 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System.IO;
+using FluentAssertions;
+using Microsoft.DotNet.TestFramework;
+using Microsoft.DotNet.Tools.Test.Utilities;
+using Xunit;
+
+namespace Microsoft.DotNet.Cli.Run.Tests
+{
+    public class GivenThatWeCanPassNonProjectFilesToDotnetRun : TestBase
+    {
+        [Fact]
+        public void ItFailsWithAnAppropriateErrorMessage()
+        {
+            var projectDirectory = TestAssets
+                .Get("SlnFileWithNoProjectReferences")
+                .CreateInstance()
+                .WithSourceFiles()
+                .Root
+                .FullName;
+
+            var slnFullPath = Path.Combine(projectDirectory, "SlnFileWithNoProjectReferences.sln");
+
+            new RunCommand()
+                .ExecuteWithCapturedOutput($"-p {slnFullPath}")
+                .Should().Fail()
+                .And.HaveStdErrContaining(
+                    string.Format(
+                        Microsoft.DotNet.Tools.Run.LocalizableStrings.RunCommandSpecifiecFileIsNotAValidProject,
+                        slnFullPath));
+        }
+    }
+}

test/dotnet-run.Tests/dotnet-run.Tests.csproj

@@ -6,11 +6,15 @@
     <RuntimeFrameworkVersion>$(CLI_SharedFrameworkVersion)</RuntimeFrameworkVersion>
     <GenerateRuntimeConfigurationFiles>true</GenerateRuntimeConfigurationFiles>
     <AssemblyName>dotnet-run.Tests</AssemblyName>
+    <AssemblyOriginatorKeyFile>../../tools/Key.snk</AssemblyOriginatorKeyFile>
+    <SignAssembly>true</SignAssembly>
+    <PublicSign Condition=" '$(OS)' != 'Windows_NT' ">true</PublicSign>
     <AssetTargetFallback>$(AssetTargetFallback);dotnet5.4;portable-net451+win8</AssetTargetFallback>
   </PropertyGroup>
 
   <ItemGroup>
     <ProjectReference Include="..\Microsoft.DotNet.Tools.Tests.Utilities\Microsoft.DotNet.Tools.Tests.Utilities.csproj" />
+    <ProjectReference Include="..\..\src\dotnet\dotnet.csproj" />
   </ItemGroup>
 
   <ItemGroup>