Matt Ward

NuGet Support in Visual Studio for Mac 7.2


  • NuGet 4.3.1 support
  • NuGet fallback folders support
  • AssetTargetFallback support
  • NuGet operations can be cancelled on closing the solution
  • Fixed transitive types from references not being available
  • Fixed credential dialog being shown multiple times on opening a solution

More information on all the new features and changes in Visual Studio for Mac 7.2 can be found in the release notes.

NuGet 4.3.1 support

NuGet is now included with Visual Studio for Mac 7.2.

NuGet 4.3.1 includes a fix for imports in the project.json file being ignored which could cause a NuGet package to incorrectly be considered incompatible when restoring NuGet packages.

NuGet package fallback folders support

The .NET Core SDK 2.0 defines a NuGet package fallback folder /usr/local/share/dotnet/sdk/NuGetFallbackFolder that can be used when looking for NuGet packages whilst restoring. This fallback folder is now supported by Visual Studio for Mac 7.2 so that on restoring a .NET Core 2.0 project the NuGet packages from the fallback folder will be found and do not need to be downloaded from into the local machine NuGet package cache ~/.nuget/packages. This should speed up NuGet package restore for .NET Core 2.0 and .NET Standard 2.0 projects the first time it occurs.

As well as the NuGet fallback folders Visual Studio for Mac will now add the following items to the generated project.assets.json if they are available:

  • configFilePaths
  • sources
  • warningProperties

AssetTargetFallback support

The .NET Core 2.0 SDK uses an AssetTargetFallback MSBuild property defined in an imported SDK MSBuild files. This is used instead of the PackageTargetFallback property when determining if a NuGet package is compatible. Currently the AssetTargetFallback property is set to net461 by the .NET Core 2.0 SDK which allows .NET Core projects to use NuGet packages that include assemblies that target the full .NET Framework. The supported fallback frameworks are now added to the generated project.assets.json file by Visual Studio for Mac when a .NET Core 2.0 project is restored.

NuGet operations can be cancelled on the closing the solution

Previously when closing the solution, or closing Visual Studio for Mac, when a NuGet package operation was still running would result in a dialog being displayed saying that the solution cannot be closed until the NuGet operation was completed. NuGet v3 and above now allow the NuGet operations to be cancelled so now the dialog allows the current operation to be cancelled. If the operation is taking a while to cancel a busy spinner image will be displayed in the dialog.

Cancel NuGet operation dialog on closing solution

If a restore is being run when the solution will be closed the restore will be cancelled automatically without showing the dialog.

NuGet package restore now fails if package and asset target fallbacks are defined by a project

If both AssetTargetFallback and PackageTargetFallback are defined by a project then the NuGet restore will fail with an error indicating that they cannot be used together. This mirrors the behaviour of the .NET Core command line restore.

Support imported package references in non .NET Core projects

If a non .NET Core project had no PackageReference items but imported a file that did have PackageReference items the NuGet packages were not restored on opening the solution. This was because only the PackageReference items defined directly in the project were checked to determine if the project used NuGet packages. Now the evaluated MSBuild items are checked so any imported PackageReference items are detected and a restore will be run on opening the solution.

Note that imported PackageReference items are not displayed in the Packages folder.

Package Console is no longer opened when a NuGet operation is cancelled

When a NuGet operation is cancelled from the main status bar the Package Console is now not opened when the NuGet operation fails due to the cancellation. If the NuGet operation is not cancelled then the Package Console window will still be opened as before if the operation fails. This is also a workaround for Visual Studio for Mac closing the currently displayed dialog when the Package Console window opens after the NuGet operation is cancelled when closing the solution.

Whitespace is now trimmed when creating a new package source

When creating a new package source copying and pasting NuGet package source url can sometimes copy extra whitespace which can then result in NuGet package restore errors such as:

Failed to verify the root directory of local source

The package source name and url will now have whitespace trimmed to avoid this copy and paste problem. This also matches Visual Studio on Windows behaviour.

Mark implicit PackageReferences as auto referenced

PackageReference items that have IsImplicitlyDefined set to true in their metadata now have autoRefererenced set to true in the project.assets.json file.

Bug Fixes

Fixed transitive assembly references not available until restart

Given a solution that contains three .NET Standard projects: LibC references LibB which references LibA. If the Newtonsoft.Json NuGet package was installed into LibA the types from this NuGet package were not available in LibB or LibC until the solution was closed and re-opened again. Closing and re-opening the solution refreshes the reference information used by the type system. Now when a NuGet package is installed into a .NET Core project the projects that reference this project have their reference information refreshed. Types from the installed NuGet packages are then available in projects that reference this updated project either directly or indirectly.

Fixed transitive project references after editing a project file

Given a solution that contains three .NET Standard projects: LibC references LibB which references LibA. If a NuGet package is added to LibA by editing its project file in the text editor the types from this NuGet package were not available to LibB or LibC without restarting Visual Studio for Mac or until the packages were restored for the solution. Now when the project file is saved the projects that directly or indirectly reference the project will be restored.

Fixed credential dialog shown multiple times on opening a solution

With check for updates enabled, multiple projects in the solution, and a package source that was missing or had invalid credentials, on opening the solution the credential dialog would be displayed multiple times even if the correct username and password was entered or the dialog was cancelled. The dialog was being displayed for each project and the credential information was not being re-used.

Now the NuGet source repositories are re-used when checking for updates and also when restoring the projects when the solution is first opened. Any valid credentials entered will be re-used when checking the remaining projects. If the credential dialog is cancelled then the dialog is no longer displayed again whilst checking for updates for the other projects.

Fixed credential dialog displayed when credentials are available

With valid credentials stored in the Mac key chain the credential dialog would still be displayed when it should not have been. The problem was that the NuGet credential service puts itself in a retry mode if any of the credential providers are used when trying to authenticate against a package source. Once in this retry mode the Visual Studio for Mac credential provider would always show a dialog asking for the credentials instead of re-using the existing credentials. To avoid this the credential service is reset before any user actions, such as opening the Add Packages dialog, running a restore or an update.

Fixed crash when displaying Chinese characters in the Add Packages dialog

With the NuGet v3 package source selected, searching for Microsoft.AspNet.WebApi.Client would result in the Visual Studio for Mac terminating when an attempt was made to display the results in the Add Packages dialog. The crash was in the Pango library when it attempted to determine the size of the package title displayed in the search results. If the package title contained Chinese characters then Pango would throw an exception:

Illegal byte sequence encounted in the input.
at (wrapper managed-to-native) Pango.Layout:pango_layout_get_pixel_size (intptr,int&,int&)

Then when Visual Studio for Mac tried to use Pango again to determine the size of the text this would result in Visual Studio for Mac terminating.

Pango-WARNING (recursed) **: shaping failure, expect ugly output.
shape-engine='BasicEngineCoreText', font='.SF NS Text',

  at <unknown> <0xffffffff>
  at (wrapper managed-to-native) Pango.Layout.pango_layout_get_pixel_size (intptr,int&,int&) [0x0000b] in <c7aa2d93df4045df8dc71d5439f99d72>:0

If the NuGet v2 package source was used then this crash did not occur since the package title was not returned in the search results and the package id would be displayed instead which does not contain Chinese characters.

As a workaround the Add Packages dialog now displays the package id instead of the package title.

Ignore project references with ReferenceOutputAssembly set to false when restoring

Project references that have ReferenceOutputAssembly are now not added to the project.assets.json file. This was causing the NuGet package restore to fail in some cases. For example, if a .NET Standard project has a project reference to a .NET Core App project, but has the ReferenceOutputAssembly set to false, then running dotnet restore from the command line would work, but the restore would fail in Visual Studio for Mac.