After NuGet started lower casing the packages, we started hitting issues where we failed to locate dependencies under our list of libraries due to different casing in the libraries names. The fix here is to compare the library names ignoring casing.

init-tools.ps1

@@ -77,6 +77,6 @@ if (!(Test-Path "$DOTNET_LOCAL_PATH"))
 }
 
 # Initialize build tools
-cmd /c "$BUILD_TOOLS_PACKAGE_PATH\init-tools.cmd $RepoRoot $env:DOTNET_INSTALL_DIR\dotnet.exe $BUILD_TOOLS_PATH" >> "$INIT_TOOLS_LOG"
+cmd /c "$BUILD_TOOLS_PACKAGE_PATH\init-tools.cmd $RepoRoot $env:DOTNET_LOCAL_PATH\dotnet.exe $BUILD_TOOLS_PATH" >> "$INIT_TOOLS_LOG"
 Write-Host "Done initializing tools."
 Write-Host "Init-Tools completed for BuildTools Version: $BUILD_TOOLS_VERSION" > $BUILD_TOOLS_SEMAPHORE

init-tools.sh

@@ -24,7 +24,7 @@ __BUILD_TOOLS_SOURCE=https://dotnet.myget.org/F/dotnet-buildtools/api/v3/index.j
 __BUILD_TOOLS_PACKAGE_VERSION=$(cat $DIR/BuildToolsVersion.txt)
 __BUILD_TOOLS_PATH=$NUGET_PACKAGES/Microsoft.DotNet.BuildTools/$__BUILD_TOOLS_PACKAGE_VERSION/lib
 __BUILD_TOOLS_SEMAPHORE=$__BUILD_TOOLS_DIR/init-tools.completed
-__DOTNET_CMD=$DOTNET_INSTALL_DIR/dotnet
+__DOTNET_CMD=$__BUILD_TOOLS_CLI_DIR/dotnet
 __PROJECT_JSON_PATH=$__BUILD_TOOLS_DIR/$__BUILD_TOOLS_PACKAGE_VERSION
 __PROJECT_JSON_FILE=$__PROJECT_JSON_PATH/project.json
 __PROJECT_JSON_CONTENTS="{ \"dependencies\": { \"Microsoft.DotNet.BuildTools\": \"$__BUILD_TOOLS_PACKAGE_VERSION\" }, \"frameworks\": { \"netcoreapp1.0\": { } } }"

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

@@ -158,7 +158,7 @@ namespace Microsoft.DotNet.Cli.Compiler.Common
         private void WriteDepsFileAndCopyProjectDependencies(LibraryExporter exporter, bool skipRuntimeConfig)
         {
             var exports = exporter.GetAllExports().ToList();
-            var exportsLookup = exports.ToDictionary(e => e.Library.Identity.Name);
+            var exportsLookup = exports.ToDictionary(e => e.Library.Identity.Name, StringComparer.OrdinalIgnoreCase);
             var platformExclusionList = _context.GetPlatformExclusionList(exportsLookup);
             var filteredExports = exports.FilterExports(platformExclusionList);
 

src/Microsoft.DotNet.ProjectModel/DependencyContextBuilder.cs

@@ -46,7 +46,7 @@ namespace Microsoft.Extensions.DependencyModel
                 .Select(export => export.Library.Identity)
                 .Distinct()
                 .Select(identity => new Dependency(identity.Name, identity.Version.ToString()))
-                .ToDictionary(dependency => dependency.Name);
+                .ToDictionary(dependency => dependency.Name, StringComparer.OrdinalIgnoreCase);
 
             var compilationOptions = compilerOptions != null
                 ? GetCompilationOptions(compilerOptions)

src/Microsoft.DotNet.ProjectModel/Graph/LockFilePatcher.cs

@@ -21,7 +21,10 @@ namespace Microsoft.DotNet.ProjectModel.Graph
             _reader = reader;
 
             var msbuildProjectLibraries = lockFile.ProjectLibraries.Where(MSBuildDependencyProvider.IsMSBuildProjectLibrary);
-            _msbuildTargetLibraries = msbuildProjectLibraries.ToDictionary(GetProjectLibraryKey, l => GetTargetsForLibrary(_lockFile, l));
+            _msbuildTargetLibraries = msbuildProjectLibraries.ToDictionary(
+                GetProjectLibraryKey,
+                l => GetTargetsForLibrary(_lockFile, l),
+                StringComparer.OrdinalIgnoreCase);
         }
 
         public void Patch()
@@ -53,7 +56,7 @@ namespace Microsoft.DotNet.ProjectModel.Graph
                 throw new LockFilePatchingException($"Export file {exportFile.ExportFilePath} has a different version than the lock file {_lockFile.LockFilePath}");
             }
 
-            var exportDict = exportFile.Exports.ToDictionary(GetTargetLibraryKey);
+            var exportDict = exportFile.Exports.ToDictionary(GetTargetLibraryKey, StringComparer.OrdinalIgnoreCase);
 
             var uncoveredLibraries = _msbuildTargetLibraries.Keys.Except(exportDict.Keys);
             if (uncoveredLibraries.Any())

src/Microsoft.DotNet.ProjectModel/ProjectContextBuilder.cs

@@ -588,7 +588,10 @@ namespace Microsoft.DotNet.ProjectModel
                     type = LibraryType.Package;
                 }
 
-                description = description ?? UnresolvedDependencyProvider.GetDescription(new LibraryRange(library.Name, type), target.TargetFramework);
+                description = description ?? 
+                              UnresolvedDependencyProvider.GetDescription(
+                                new LibraryRange(library.Name, type),
+                                target.TargetFramework);
 
                 libraries.Add(new LibraryKey(library.Name), description);
             }
@@ -674,14 +677,14 @@ namespace Microsoft.DotNet.ProjectModel
             {
                 var otherKey = (LibraryKey)obj;
 
-                return string.Equals(otherKey.Name, Name, StringComparison.Ordinal) &&
+                return string.Equals(otherKey.Name, Name, StringComparison.OrdinalIgnoreCase) &&
                     otherKey.LibraryType.Equals(LibraryType);
             }
 
             public override int GetHashCode()
             {
                 var combiner = new HashCodeCombiner();
-                combiner.Add(Name);
+                combiner.Add(Name.ToLowerInvariant());
                 combiner.Add(LibraryType);
 
                 return combiner.CombinedHash;

src/Microsoft.DotNet.ProjectModel/Resolution/ProjectDependencyProvider.cs

@@ -67,7 +67,9 @@ namespace Microsoft.DotNet.ProjectModel.Resolution
             if (targetLibrary != null)
             {
                 // The lock file entry might have a filtered set of dependencies
-                var lockFileDependencies = targetLibrary.Dependencies.ToDictionary(d => d.Id);
+                var lockFileDependencies = targetLibrary.Dependencies.ToDictionary(
+                    d => d.Id,
+                    StringComparer.OrdinalIgnoreCase);
 
                 // Remove all non-framework dependencies that don't appear in the lock file entry
                 dependencies.RemoveAll(m => !lockFileDependencies.ContainsKey(m.Name) && m.Target != LibraryType.ReferenceAssembly);

src/Microsoft.Extensions.DependencyModel/DependencyContextWriter.cs

@@ -124,8 +124,8 @@ namespace Microsoft.Extensions.DependencyModel
 
         private JObject WritePortableTarget(IReadOnlyList<RuntimeLibrary> runtimeLibraries, IReadOnlyList<CompilationLibrary> compilationLibraries)
         {
-            var runtimeLookup = runtimeLibraries.ToDictionary(l => l.Name);
+            var runtimeLookup = runtimeLibraries.ToDictionary(l => l.Name, StringComparer.OrdinalIgnoreCase);
-            var compileLookup = compilationLibraries.ToDictionary(l => l.Name);
+            var compileLookup = compilationLibraries.ToDictionary(l => l.Name, StringComparer.OrdinalIgnoreCase);
 
             var targetObject = new JObject();
 

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

@@ -28,7 +28,7 @@ namespace Microsoft.DotNet.Tools.Build
             foreach (var context in contexts)
             {
                 var libraries = context.LibraryManager.GetLibraries();
-                var lookup = libraries.ToDictionary(l => l.Identity.Name);
+                var lookup = libraries.ToDictionary(l => l.Identity.Name, StringComparer.OrdinalIgnoreCase);
                 var root = lookup[context.ProjectFile.Name];
                 yield return TraverseProject((ProjectDescription) root, lookup, context);
             }

src/dotnet/commands/dotnet-compile/CompilerUtil.cs

@@ -96,10 +96,13 @@ namespace Microsoft.DotNet.Tools.Compiler
         public static List<CultureResgenIO> GetCultureResources(Project project, string outputPath)
         {
             return
-                (from resourceFileGroup in project.Files.ResourceFiles.GroupBy(resourceFile => ResourceUtility.GetResourceCultureName(resourceFile.Key))
+                (from resourceFileGroup in project.Files.ResourceFiles.GroupBy(
+                    resourceFile => ResourceUtility.GetResourceCultureName(resourceFile.Key))
                  let culture = resourceFileGroup.Key
                  where !string.IsNullOrEmpty(culture)
-                 let inputFileToMetadata = resourceFileGroup.ToDictionary(r => r.Key, r => GetResourceFileMetadataName(project, r.Key, r.Value))
+                 let inputFileToMetadata = resourceFileGroup.ToDictionary(
+                     r => r.Key,
+                     r => GetResourceFileMetadataName(project, r.Key, r.Value))
                  let resourceOutputPath = Path.Combine(outputPath, culture)
                  let outputFile = Path.Combine(resourceOutputPath, project.Name + ".resources.dll")
                  select new CultureResgenIO(culture, inputFileToMetadata, outputFile)

src/dotnet/commands/dotnet-compile/ManagedCompiler.cs

@@ -126,7 +126,9 @@ namespace Microsoft.DotNet.Tools.Compiler
             if (compilationOptions.PreserveCompilationContext == true)
             {
                 var allExports = exporter.GetAllExports().ToList();
-                var exportsLookup = allExports.ToDictionary(e => e.Library.Identity.Name);
+                var exportsLookup = allExports.ToDictionary(
+                    e => e.Library.Identity.Name,
+                    StringComparer.OrdinalIgnoreCase);
                 var buildExclusionList = context.GetTypeBuildExclusionList(exportsLookup);
                 var filteredExports = allExports
                     .Where(e => e.Library.Identity.Type.Equals(LibraryType.ReferenceAssembly) ||

src/dotnet/commands/dotnet-publish/PublishCommand.cs

@@ -134,7 +134,7 @@ namespace Microsoft.DotNet.Tools.Publish
 
             var exports = exporter.GetAllExports();
 
-            var exportsLookup = exports.ToDictionary(e => e.Library.Identity.Name);
+            var exportsLookup = exports.ToDictionary(e => e.Library.Identity.Name, StringComparer.OrdinalIgnoreCase);
             var platformExclusionList = context.GetPlatformExclusionList(exportsLookup);
             var buildExclusionList = context.GetTypeBuildExclusionList(exportsLookup);
             var allExclusionList = new HashSet<string>(platformExclusionList);

test/Microsoft.DotNet.ProjectModel.Tests/PackageDependencyProviderTests.cs

@@ -126,7 +126,7 @@ namespace Microsoft.DotNet.ProjectModel.Tests
                                                      .Build();
 
             // Will fail with dupes if any
-            context.LibraryManager.GetLibraries().ToDictionary(l => l.Identity.Name);
+            context.LibraryManager.GetLibraries().ToDictionary(l => l.Identity.Name, StringComparer.OrdinalIgnoreCase);
         }
 
         [Fact]
@@ -153,7 +153,7 @@ namespace Microsoft.DotNet.ProjectModel.Tests
                                                      .Build();
 
             // Will fail with dupes if any
-            context.LibraryManager.GetLibraries().ToDictionary(l => l.Identity.Name);
+            context.LibraryManager.GetLibraries().ToDictionary(l => l.Identity.Name, StringComparer.OrdinalIgnoreCase);
         }
     }
 }