fixes #2760

Verify coreclr absence/presence depending on app type during dotnet build.

TestAssets/TestProjects/DependencyChangeTest/PortableApp_Standalone/Program.cs

@@ -0,0 +1,12 @@
+using System;
+
+namespace PortableApp
+{
+    public static class Program
+    {
+        public static void Main(string[] args)
+        {
+            Console.WriteLine("Hello, World!");
+        }
+    }
+}

TestAssets/TestProjects/DependencyChangeTest/PortableApp_Standalone/project.json

@@ -0,0 +1,17 @@
+{
+  "compilationOptions": {
+    "emitEntryPoint": true
+  },
+  "dependencies": {},
+  "frameworks": {
+    "netcoreapp1.0": {
+      "dependencies": {
+        "Microsoft.NETCore.App": {
+          "type": "platform",
+          "version": "1.0.0-rc2-*"
+        }
+      }
+    }
+  }
+}
+

TestAssets/TestProjects/DependencyChangeTest/PortableApp_Standalone/project.json.modified

@@ -0,0 +1,26 @@
+{
+  "compilationOptions": {
+    "emitEntryPoint": true
+  },
+  "dependencies": {},
+  "frameworks": {
+    "netcoreapp1.0": {
+      "dependencies": {
+        "Microsoft.NETCore.App": {
+          "version": "1.0.0-rc2-*"
+        }
+      }
+    }
+  },
+
+  "runtimes": {
+    "win7-x64": {},
+    "win7-x86": {},
+    "osx.10.10-x64": {},
+    "osx.10.11-x64": {},
+    "ubuntu.14.04-x64": {},
+    "centos.7-x64": {},
+    "rhel.7.2-x64": {},
+    "debian.8-x64": {}
+  }
+}

TestAssets/TestProjects/DependencyChangeTest/StandaloneApp_Portable/Program.cs

@@ -0,0 +1,12 @@
+using System;
+
+namespace StandaloneApp
+{
+    public static class Program
+    {
+        public static void Main(string[] args)
+        {
+            Console.WriteLine("Hello, World!");
+        }
+    }
+}

TestAssets/TestProjects/DependencyChangeTest/StandaloneApp_Portable/project.json

@@ -0,0 +1,22 @@
+{
+  "compilationOptions": {
+    "emitEntryPoint": true
+  },
+  "frameworks": {
+    "netcoreapp1.0": {
+      "dependencies": {
+        "Microsoft.NETCore.App": "1.0.0-rc2-*"
+      }
+    }
+  },
+  "runtimes": {
+    "win7-x64": {},
+    "win7-x86": {},
+    "osx.10.10-x64": {},
+    "osx.10.11-x64": {},
+    "ubuntu.14.04-x64": {},
+    "centos.7-x64": {},
+    "rhel.7.2-x64": {},
+    "debian.8-x64": {}
+  }
+}

TestAssets/TestProjects/DependencyChangeTest/StandaloneApp_Portable/project.json.modified

@@ -0,0 +1,25 @@
+{
+  "compilationOptions": {
+    "emitEntryPoint": true
+  },
+  "frameworks": {
+    "netcoreapp1.0": {
+      "dependencies": {
+       "Microsoft.NETCore.App": {
+          "type": "platform",
+          "version": "1.0.0-rc2-*"
+        }
+      }
+    }
+  },
+  "runtimes": {
+    "win7-x64": {},
+    "win7-x86": {},
+    "osx.10.10-x64": {},
+    "osx.10.11-x64": {},
+    "ubuntu.14.04-x64": {},
+    "centos.7-x64": {},
+    "rhel.7.2-x64": {},
+    "debian.8-x64": {}
+  }
+}

src/Microsoft.DotNet.Cli.Utils/Constants.cs

@@ -43,5 +43,12 @@ namespace Microsoft.DotNet.Cli.Utils
             (CurrentPlatform == Platform.Windows ? "hostfxr" : "libhostfxr") + DynamicLibSuffix
         };
 
+        public static readonly string[] LibCoreClrBinaryNames = new string[] 
+        {
+            "coreclr.dll",
+            "libcoreclr.so",
+            "libcoreclr.dylib"
+        };
+
     }
 }

src/Microsoft.DotNet.Compiler.Common/Executable.cs

@@ -56,6 +56,23 @@ namespace Microsoft.DotNet.Cli.Compiler.Common
             ExportRuntimeAssets();
         }
 
+        private void VerifyCoreclrPresenceInPackageGraph()
+        {
+            var isCoreclrPresent = _exporter
+                .GetAllExports()
+                .SelectMany(e => e.NativeLibraryGroups)
+                .SelectMany(g => g.Assets)
+                .Select(a => a.FileName)
+                .Where(f => Constants.LibCoreClrBinaryNames.Contains(f))
+                .Any();
+
+            // coreclr should be present for standalone apps
+            if (! isCoreclrPresent)
+            {
+                throw new InvalidOperationException("Expected coreclr library not found in package graph. Please try running restore again.");
+            }
+        }
+
         private void ExportRuntimeAssets()
         {
             if (_context.TargetFramework.IsDesktop())
@@ -77,13 +94,15 @@ namespace Microsoft.DotNet.Cli.Compiler.Common
         }
 
         private void MakeCompilationOutputRunnableForCoreCLR()
-        {
+        {   
             WriteDepsFileAndCopyProjectDependencies(_exporter);
 
             var emitEntryPoint = _compilerOptions.EmitEntryPoint ?? false;
-            if (emitEntryPoint && !string.IsNullOrEmpty(_context.RuntimeIdentifier))
+
+            if (emitEntryPoint && !_context.IsPortable)
             {
                 // TODO: Pick a host based on the RID
+                VerifyCoreclrPresenceInPackageGraph();
                 CoreHost.CopyTo(_runtimeOutputPath, _compilerOptions.OutputName + Constants.ExeSuffix);
             }
         }

src/dotnet/commands/dotnet-build/DotnetProjectBuilder.cs

@@ -129,7 +129,7 @@ namespace Microsoft.DotNet.Tools.Build
             }
             catch (Exception e)
             {
-                throw new Exception($"Failed to make the following project runnable: {graphNode.ProjectContext.GetDisplayName()}", e);
+                throw new Exception($"Failed to make the following project runnable: {graphNode.ProjectContext.GetDisplayName()} reason: {e.Message}", e);
             }
         }
 

test/dotnet-build.Tests/BuildOutputTests.cs

@@ -307,6 +307,30 @@ namespace Microsoft.DotNet.Tools.Builder.Tests
             }
 
         }
+
+        [Fact]
+        private void StandaloneApp_WithoutCoreclrDll_Fails()
+        {
+            // Convert a Portable App to Standalone to simulate the customer scenario
+            var testInstance = TestAssetsManager.CreateTestInstance("DependencyChangeTest")
+                                .WithLockFiles();
+
+            // Convert the portable test project to standalone by removing "type": "platform" and adding rids
+            var originalTestProject = Path.Combine(testInstance.TestRoot, "PortableApp_Standalone", "project.json");
+            var modifiedTestProject = Path.Combine(testInstance.TestRoot, "PortableApp_Standalone", "project.json.modified");
+
+            // Simulate a user editting the project.json
+            File.Delete(originalTestProject);
+            File.Copy(modifiedTestProject, originalTestProject);
+
+            var buildResult = new BuildCommand(originalTestProject, framework: DefaultFramework)
+                .ExecuteWithCapturedOutput();
+
+            buildResult.Should().Fail();
+
+            buildResult.StdErr.Should().Contain("Expected coreclr library not found in package graph. Please try running restore again.");
+        }
+
         private void CopyProjectToTempDir(string projectDir, TempDirectory tempDir)
         {
             // copy all the files to temp dir