From b20dc8212d57adc1f122e5d3c837e327d2065e60 Mon Sep 17 00:00:00 2001
From: Daniel Plaisted <daplaist@microsoft.com>
Date: Thu, 25 May 2017 14:53:20 -0700
Subject: [PATCH] Don't pass duplicate items to conflict resolution if
 CopyLocalLockFileAssemblies is true

Fixes #1135
---
 .../Microsoft.NET.ConflictResolution.targets  |  8 +++-
 .../GivenThatWeWantToBuildADesktopExe.cs      | 40 +++++++++++++++++++
 2 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/src/Tasks/Microsoft.NET.Build.Tasks/build/Microsoft.NET.ConflictResolution.targets b/src/Tasks/Microsoft.NET.Build.Tasks/build/Microsoft.NET.ConflictResolution.targets
index 3fe79f7da911..0a53a4a01d8a 100644
--- a/src/Tasks/Microsoft.NET.Build.Tasks/build/Microsoft.NET.ConflictResolution.targets
+++ b/src/Tasks/Microsoft.NET.Build.Tasks/build/Microsoft.NET.ConflictResolution.targets
@@ -22,9 +22,13 @@ Copyright (c) .NET Foundation. All rights reserved.
     
     <ItemGroup>
       <!-- We need to find all the files that will be loaded from deps for conflict resolution.
-          To do this, we look at the files that would be copied local when CopyLocalLockFileAssemblies is true
+          To do this, we look at the files that would be copied local when CopyLocalLockFileAssemblies is true.
+          However, if CopyLocalLockFileAssemblies is true, then we don't add these items, as they
+          will always be included in ReferenceCopyLocalPaths.
           -->
-      <_LockFileAssemblies Include="@(AllCopyLocalItems->WithMetadataValue('Type', 'assembly'))" />
+      <_LockFileAssemblies Include="@(AllCopyLocalItems->WithMetadataValue('Type', 'assembly'))"
+                           Condition="'$(CopyLocalLockFileAssemblies)' != 'true'"
+                           />
 
       
       <!-- Also include RuntimeTarget items, which aren't included in AllCopyLocalItems, but need to be considered
diff --git a/test/Microsoft.NET.Build.Tests/GivenThatWeWantToBuildADesktopExe.cs b/test/Microsoft.NET.Build.Tests/GivenThatWeWantToBuildADesktopExe.cs
index cb1c1fc5709a..d78b25d6c31c 100644
--- a/test/Microsoft.NET.Build.Tests/GivenThatWeWantToBuildADesktopExe.cs
+++ b/test/Microsoft.NET.Build.Tests/GivenThatWeWantToBuildADesktopExe.cs
@@ -350,6 +350,46 @@ public void It_does_not_report_conflicts_if_the_same_framework_assembly_is_refer
                 .NotHaveStdOutMatching("Encountered conflict", System.Text.RegularExpressions.RegexOptions.CultureInvariant | System.Text.RegularExpressions.RegexOptions.IgnoreCase);
         }
 
+        [Fact]
+        public void It_does_not_report_conflicts_when_referencing_a_nuget_package()
+        {
+            if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+            {
+                return;
+            }
+
+            var testProject = new TestProject()
+            {
+                Name = "DesktopConflictsNuGet",
+                TargetFrameworks = "net461",
+                IsSdkProject = true,
+                IsExe = true
+            };
+
+            var testAsset = _testAssetsManager.CreateTestProject(testProject, testProject.Name)
+                .WithProjectChanges(p =>
+                {
+                    var ns = p.Root.Name.Namespace;
+
+                    var itemGroup = new XElement(ns + "ItemGroup");
+                    p.Root.Add(itemGroup);
+
+                    itemGroup.Add(new XElement(ns + "PackageReference",
+                                    new XAttribute("Include", "NewtonSoft.Json"),
+                                    new XAttribute("Version", "9.0.1")));
+                })
+                .Restore(Log, testProject.Name);
+
+            var buildCommand = new BuildCommand(Log, Path.Combine(testAsset.TestRoot, testProject.Name));
+
+            buildCommand
+                .Execute("/v:diag")
+                .Should()
+                .Pass()
+                .And
+                .NotHaveStdOutMatching("Encountered conflict", System.Text.RegularExpressions.RegexOptions.CultureInvariant | System.Text.RegularExpressions.RegexOptions.IgnoreCase);
+        }
+
         [Fact]
         public void It_generates_binding_redirects_if_needed()
         {