fix pack issue with readmes and snupkgs

src/NuGet.Core/NuGet.Packaging/PackageCreation/Authoring/PackageBuilder.cs

@@ -859,14 +859,14 @@ private static void ValidateFileFrameworks(IEnumerable<IPackageFile> files)
         }
 
         /// <summary>
-        /// Validate that the readme file is of the correct size/type and can be opened properly.
+        /// Validate that the readme file is of the correct size/type and can be opened properly except for Symbol packages.
         /// </summary>
         /// <param name="files">Files resolved from the file entries in the nuspec</param>
         /// <param name="readmePath">readmepath found in the .nuspec</param>
         /// <exception cref="PackagingException">When a validation rule is not met</exception>
         private void ValidateReadmeFile(IEnumerable<IPackageFile> files, string readmePath)
         {
-            if (!string.IsNullOrEmpty(readmePath))
+            if (!PackageTypes.Contains(PackageType.SymbolsPackage) && !string.IsNullOrEmpty(readmePath))
             {
                 // Validate readme extension
                 var extension = Path.GetExtension(readmePath);

src/NuGet.Core/NuGet.Packaging/PackageCreation/Xml/PackageMetadataXmlExtensions.cs

@@ -69,8 +69,8 @@ public static XElement ToXElement(this ManifestMetadata metadata, XNamespace ns,
                     }
                 }
                 AddElementIfNotNull(elem, ns, "licenseUrl", licenseUrlToWrite);
-
                 AddElementIfNotNull(elem, ns, "icon", metadata.Icon);
+                AddElementIfNotNull(elem, ns, "readme", metadata.Readme);
             }
             AddElementIfNotNull(elem, ns, "projectUrl", metadata.ProjectUrl);
             AddElementIfNotNull(elem, ns, "iconUrl", metadata.IconUrl);
@@ -80,7 +80,6 @@ public static XElement ToXElement(this ManifestMetadata metadata, XNamespace ns,
             AddElementIfNotNull(elem, ns, "copyright", metadata.Copyright);
             AddElementIfNotNull(elem, ns, "language", metadata.Language);
             AddElementIfNotNull(elem, ns, "tags", metadata.Tags);
-            AddElementIfNotNull(elem, ns, "readme", metadata.Readme);
             if (metadata.Serviceable)
             {
                 elem.Add(new XElement(ns + "serviceable", metadata.Serviceable));

test/NuGet.Core.FuncTests/Dotnet.Integration.Test/PackCommandTests.cs

@@ -5440,6 +5440,56 @@ public void PackCommand_PackageReadmeFile_ReadmeFileIsEmpty_Fails()
             }
         }
 
+        [PlatformFact(Platform.Windows)]
+        public void PackCommand_PackageReadmeFile_BasicFunc_WithSymbol_Succeeds()
+        {
+            // Arrange
+            TestDirectoryBuilder testDirBuilder = TestDirectoryBuilder.Create();
+            ProjectFileBuilder projectBuilder = ProjectFileBuilder.Create();
+
+            testDirBuilder
+                .WithFile("test\\readme.md", 10)
+                .WithFile("test\\folder\\notes.txt", 10)
+                .WithFile("test\\folder\\nested\\content.txt", 10)
+                .WithFile("test\\folder\\nested\\sample.txt", 10)
+                .WithFile("test\\icon.jpg", 10)
+                .WithFile("test\\other\\files.txt", 10)
+                .WithFile("test\\utils\\sources.txt", 10);
+
+            projectBuilder
+                .WithProjectName("test")
+                .WithProperty("IncludeSymbols", "true")
+                .WithProperty("SymbolPackageFormat", "snupkg")
+                .WithPackageReadmeFile("readme.md")
+                .WithItem(itemType: "None", itemPath: "readme.md", packagePath: string.Empty, pack: "true")
+                .WithItem(itemType: "None", itemPath: "other\\files.txt", packagePath: null, pack: "true")
+                .WithItem(itemType: "None", itemPath: "folder\\**", packagePath: "media", pack: "true")
+                .WithItem(itemType: "None", itemPath: "utils\\*", packagePath: "utils", pack: "true");
+
+            // Act
+            using (TestDirectory srcDir = msbuildFixture.Build(testDirBuilder))
+            {
+                projectBuilder.Build(msbuildFixture, srcDir.Path);
+                msbuildFixture.PackProject(projectBuilder.ProjectFolder, projectBuilder.ProjectName, string.Empty);
+
+                // Assert
+                // Validate embedded readme in package
+                ValidatePackReadme(projectBuilder);
+
+                // Validate that other content is also included
+                string nupkgPath = Path.Combine(projectBuilder.ProjectFolder, "bin", "Debug", $"{projectBuilder.ProjectName}.1.0.0.nupkg");
+                using (var nupkgReader = new PackageArchiveReader(nupkgPath))
+                {
+                    Assert.NotNull(nupkgReader.GetEntry("content/other/files.txt"));
+                    Assert.NotNull(nupkgReader.GetEntry("utils/sources.txt"));
+                    Assert.NotNull(nupkgReader.GetEntry("media/nested/sample.txt"));
+                }
+
+                string snupkgPath = Path.Combine(projectBuilder.ProjectFolder, "bin", "Debug", $"{projectBuilder.ProjectName}.1.0.0.snupkg");
+                Assert.True(File.Exists(snupkgPath), "No snupkg was produced");
+            }
+        }
+
         private void ValidatePackReadme(ProjectFileBuilder projectBuilder)
         {
             Assert.True(File.Exists(projectBuilder.ProjectFilePath), "No project was produced");