In conflict resolution, treat items from FrameworkList.xml as platform assemblies

src/Tasks/Common/Resources/Strings.resx

@@ -315,4 +315,10 @@
   <data name="UnsupportedSDKVersionForNetStandard20" xml:space="preserve">
     <value>The version of Microsoft.NET.Sdk used by this project is insufficient to support references to libraries targeting .NET Standard 1.5 or higher.  Please install version 2.0 or higher of the .NET Core SDK.</value>
   </data>
+  <data name="ErrorParsingFrameworkListInvalidValue" xml:space="preserve">
+    <value>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</value>
+  </data>
+  <data name="FrameworkListPathNotRooted" xml:space="preserve">
+    <value>Framework list file path '{0}' is not rooted. Only full paths are supported.</value>
+  </data>
 </root>

src/Tasks/Common/Resources/xlf/Strings.cs.xlf

@@ -332,6 +332,16 @@
         <target state="translated">Platforma RuntimeIdentifier a PlatformTarget se musí shodovat.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.de.xlf

@@ -332,6 +332,16 @@
         <target state="translated">Die RuntimeIdentifier-Plattform und PlatformTarget müssen übereinstimmen.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.es.xlf

@@ -332,6 +332,16 @@
         <target state="translated">Las plataformas RuntimeIdentifier y PlatformTarget deben coincidir.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.fr.xlf

@@ -332,6 +332,16 @@
         <target state="translated">La plateforme RuntimeIdentifier et la PlatformTarget doivent correspondre.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.it.xlf

@@ -332,6 +332,16 @@
         <target state="translated">La piattaforma di RuntimeIdentifier e quella di PlatformTarget devono corrispondere.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.ja.xlf

@@ -332,6 +332,16 @@
         <target state="translated">RuntimeIdentifier プラットフォームと PlatformTarget は一致している必要があります。</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.ko.xlf

@@ -332,6 +332,16 @@
         <target state="translated">RuntimeIdentifier 플랫폼과 PlatformTarget은 일치해야 합니다.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.pl.xlf

@@ -332,6 +332,16 @@
         <target state="translated">Platforma RuntimeIdentifier i wartość PlatformTarget muszą być zgodne.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.pt-BR.xlf

@@ -332,6 +332,16 @@
         <target state="translated">A plataforma RuntimeIdentifier e a PlatformTarget devem corresponder.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.ru.xlf

@@ -332,6 +332,16 @@
         <target state="translated">Платформа RuntimeIdentifier и PlatformTarget должны совпадать.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.tr.xlf

@@ -332,6 +332,16 @@
         <target state="translated">RuntimeIdentifier platformu ile PlatformTarget eşleşmelidir.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.zh-Hans.xlf

@@ -332,6 +332,16 @@
         <target state="translated">RuntimeIdentifier 平台和 PlatformTarget 必须匹配。</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/Resources/xlf/Strings.zh-Hant.xlf

@@ -332,6 +332,16 @@
         <target state="translated">RuntimeIdentifier 平台必須與 PlatformTarget 相符。</target>
         <note />
       </trans-unit>
+      <trans-unit id="ErrorParsingFrameworkListInvalidValue">
+        <source>Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</source>
+        <target state="new">Error parsing FrameworkList from '{0}'.  {1} '{2}' was invalid.</target>
+        <note />
+      </trans-unit>
+      <trans-unit id="FrameworkListPathNotRooted">
+        <source>Framework list file path '{0}' is not rooted. Only full paths are supported.</source>
+        <target state="new">Framework list file path '{0}' is not rooted. Only full paths are supported.</target>
+        <note />
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Tasks/Common/src/ConflictResolution/ConflictResolver.cs

@@ -248,7 +248,7 @@ private TConflictItem ResolveConflict(TConflictItem item1, TConflictItem item2)
                 return item2;
             }
 
-            string message = conflictMessage + SENTENCE_SPACING + string.Format(CultureInfo.InvariantCulture, Strings.ConflictCouldNotDetermineWinner);
+            string message = conflictMessage + SENTENCE_SPACING + string.Format(CultureInfo.CurrentCulture, Strings.ConflictCouldNotDetermineWinner);
 
             log.LogMessage(message);
             return null;

src/Tasks/Common/src/ConflictResolution/FrameworkListReader.cs

@@ -0,0 +1,103 @@
+// 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 Microsoft.NET.Build.Tasks;
+using Microsoft.Build.Utilities;
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.IO;
+using System.Xml.Linq;
+using System.Linq;
+using Microsoft.Build.Framework;
+
+namespace Microsoft.NET.Build.Tasks.ConflictResolution
+{
+    class FrameworkListReader
+    {
+        private IBuildEngine4 _buildEngine;
+
+        public FrameworkListReader(IBuildEngine4 buildEngine)
+        {
+            _buildEngine = buildEngine;
+        }
+
+        public IEnumerable<ConflictItem> GetConflictItems(string frameworkListPath, ILog log)
+        {
+            if (frameworkListPath == null)
+            {
+                throw new ArgumentNullException(nameof(frameworkListPath));
+            }
+
+            if (!Path.IsPathRooted(frameworkListPath))
+            {
+                throw new BuildErrorException(Strings.FrameworkListPathNotRooted, frameworkListPath);
+            }
+
+            string objectKey = $"{nameof(FrameworkListReader)}:{frameworkListPath}";
+
+            IEnumerable<ConflictItem> result;
+
+            object existingConflictItems = _buildEngine.GetRegisteredTaskObject(objectKey, RegisteredTaskObjectLifetime.AppDomain);
+
+            if (existingConflictItems == null)
+            {
+                result = LoadConflictItems(frameworkListPath, log);
+
+                _buildEngine.RegisterTaskObject(objectKey, result, RegisteredTaskObjectLifetime.AppDomain, true);
+            }
+            else
+            {
+                result = (IEnumerable<ConflictItem>)existingConflictItems;
+            }
+
+            return result;
+        }
+
+        private static IEnumerable<ConflictItem> LoadConflictItems(string frameworkListPath, ILog log)
+        {
+            if (!File.Exists(frameworkListPath))
+            {
+                //  This is not an error, as we get both the root target framework directory as well as the Facades folder passed in as TargetFrameworkDirectories.
+                //  Only the root will have a RedistList\FrameworkList.xml in it
+                return Enumerable.Empty<ConflictItem>();
+            }
+
+            var frameworkList = XDocument.Load(frameworkListPath);
+            var ret = new List<ConflictItem>();
+            foreach (var file in frameworkList.Root.Elements("File"))
+            {
+                var assemblyName = file.Attribute("AssemblyName")?.Value;
+                var assemblyVersionString = file.Attribute("Version")?.Value;
+
+                if (string.IsNullOrEmpty(assemblyName))
+                {
+                    string errorMessage = string.Format(CultureInfo.CurrentCulture, Strings.ErrorParsingFrameworkListInvalidValue,
+                        frameworkListPath,
+                        "AssemblyName",
+                        assemblyName);
+                    log.LogError(errorMessage);
+                    return Enumerable.Empty<ConflictItem>();
+                }
+
+                Version assemblyVersion;
+                if (string.IsNullOrEmpty(assemblyVersionString) || !Version.TryParse(assemblyVersionString, out assemblyVersion))
+                {
+                    string errorMessage = string.Format(CultureInfo.CurrentCulture, Strings.ErrorParsingFrameworkListInvalidValue,
+                        frameworkListPath,
+                        "Version",
+                        assemblyVersionString);
+                    log.LogError(errorMessage);
+                    return Enumerable.Empty<ConflictItem>();
+                }
+
+                ret.Add(new ConflictItem(assemblyName + ".dll",
+                                                packageId: null,
+                                                assemblyVersion: assemblyVersion,
+                                                fileVersion: null));
+            }
+
+            return ret;
+        }
+    }
+}