VerifyVersionsTask fails when using neither packages.config nor PackageReference

[TimLariviere]

Xamarin.Android Version (eg: 6.0):

9.0

Operating System & Version (eg: Mac OSX 10.11):

macOS Mojave 10.14.5

Support Libraries Version (eg: 23.3.0):

28.0.0.1

Describe your Issue:

Referencing Xamarin.Android.Support.Annotations.targets in a project that doesn't use neither packages.config nor PackageReference (but uses an external package manager such as Paket) fails on the VerifyVersionsTask.

It expects to find obj/project.assets.json which doesn't exist.

I think the issue is due to this if statement that has only 2 cases.

https://github.com/xamarin/AndroidSupportComponents/blob/f2e01b6f80591628628a60c801d8cfb1a8aa7304/source/buildtasks/support-annotations/VerifyVersionsTask.cs#L62-L71

Steps to Reproduce (with link to sample solution if possible):

1. Create a C# Xamarin.Android project (from the templates of VS Mac)
2. Remove the packages.config file or the PackageReference nodes from the csproj
3. Manually reference the packages including Xamarin.Android.Support.Annotations (or use Paket for that)
4. Make sure the targets file is imported in the csproj

<Import Project="..\packages\Xamarin.Android.Support.Annotations\build\monoandroid90\Xamarin.Android.Support.Annotations.targets" />

4. Build the project

Other reproduction:

1. Clone https://github.com/TimLariviere/XFIssueRepros/tree/master/SupportAnnotationsIssue/testcrashsupport
2. Run the command at the root of the folder testcrashsupport: mono .paket/paket.exe restore
3. Run the command msbuild

Include any relevant Exception Stack traces, build logs, adb logs:

"/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj" (default target) (1) ->
(_VerifyXamarinAndroidSupportVersions target) -> 
  /Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018: The "VerifyVersionsTask" task failed unexpectedly. [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018: System.IO.FileNotFoundException: Could not find file "/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/obj/project.assets.json" [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018: File name: '/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/obj/project.assets.json' [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at System.IO.FileStream..ctor (System.String path, System.IO.FileMode mode, System.IO.FileAccess access, System.IO.FileShare share, System.Int32 bufferSize, System.Boolean anonymous, System.IO.FileOptions options) [0x0019e] in <b4d1a66727f44ba888b54966284fabb4>:0  [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at System.IO.FileStream..ctor (System.String path, System.IO.FileMode mode, System.IO.FileAccess access, System.IO.FileShare share, System.Int32 bufferSize, System.IO.FileOptions options, System.String msgPath, System.Boolean bFromProxy, System.Boolean useLongPath, System.Boolean checkHost) [0x00000] in <b4d1a66727f44ba888b54966284fabb4>:0  [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at (wrapper remoting-invoke-with-check) System.IO.FileStream..ctor(string,System.IO.FileMode,System.IO.FileAccess,System.IO.FileShare,int,System.IO.FileOptions,string,bool,bool,bool) [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at System.IO.StreamReader..ctor (System.String path, System.Text.Encoding encoding, System.Boolean detectEncodingFromByteOrderMarks, System.Int32 bufferSize, System.Boolean checkHost) [0x00067] in <b4d1a66727f44ba888b54966284fabb4>:0  [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at System.IO.StreamReader..ctor (System.String path, System.Text.Encoding encoding, System.Boolean detectEncodingFromByteOrderMarks, System.Int32 bufferSize) [0x00000] in <b4d1a66727f44ba888b54966284fabb4>:0  [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at System.IO.StreamReader..ctor (System.String path, System.Boolean detectEncodingFromByteOrderMarks) [0x0000d] in <b4d1a66727f44ba888b54966284fabb4>:0  [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at System.IO.StreamReader..ctor (System.String path) [0x00000] in <b4d1a66727f44ba888b54966284fabb4>:0  [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at (wrapper remoting-invoke-with-check) System.IO.StreamReader..ctor(string) [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at System.IO.File.ReadAllText (System.String path) [0x00000] in <b4d1a66727f44ba888b54966284fabb4>:0  [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at Xamarin.Android.Support.BuildTasks.NugetPackages.GatherProjectJsonVersions (System.String packageIdPrefix, System.String projectExtensionsPath, System.Collections.Generic.IEnumerable`1[T] excludedPackages, System.Version monoandroidVersion, System.Collections.Generic.Dictionary`2[TKey,TValue] packageVersions, Microsoft.Build.Utilities.TaskLoggingHelper log) [0x00011] in <44cd994afc7545758ea279b67fdd7f4e>:0  [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at Xamarin.Android.Support.BuildTasks.VerifyVersionsTask.Execute () [0x00198] in <44cd994afc7545758ea279b67fdd7f4e>:0  [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute () [0x00029] in <77054ab36c6842898cd2b21ace6de68e>:0  [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]
/Git/Github/Fabulous/packages/androidapp/Xamarin.Android.Support.Annotations/build/monoandroid90/Xamarin.Android.Support.Annotations.targets(17,3): error MSB4018:   at Microsoft.Build.BackEnd.TaskBuilder.ExecuteInstantiatedTask (Microsoft.Build.BackEnd.ITaskExecutionHost taskExecutionHost, Microsoft.Build.BackEnd.Logging.TaskLoggingContext taskLoggingContext, Microsoft.Build.BackEnd.TaskHost taskHost, Microsoft.Build.BackEnd.ItemBucket bucket, Microsoft.Build.BackEnd.TaskExecutionMode howToExecuteTask) [0x001f6] in <77054ab36c6842898cd2b21ace6de68e>:0  [/Git/Github/Fabulous/samples/Shell/Fabimals/Droid/Fabimals.Droid.fsproj]

[logeshpalani30]

Downgrade your package version 28.0.0.2 to 28.0.0.1, it works for me

[eman1986]

is there an ETA on when this will be fixed?

[TimLariviere]

This issue is not related to the bugged 28.0.0.2

[JuanuMusic]

I confirm this issue once I updated to version 9.0 and above

[tim-brand]

This issue is not related to the bugged 28.0.0.2

True. I'm having the same with 28.0.0.1 Seems indeed started to happen since upgrading to 9.0, but this is required for at lease one of the packages I need.

[tim-brand]

I noticed there's a 28.0.0.3 release. But this isn't available as nuget yet. Will this fix the issue?

[stroborobo]

This is very unfortunate as Xamarin.Essentials requires API version 28.

[iashaik]

I noticed there's a 28.0.0.3 release. But this isn't available as NuGet yet. Will this fix the issue?

28.0.0.3 Doesn't help either, I am stuck with my development.

It occurs on all the machines that I tried, I have at least 5 packages (Firebase) that require v.9 and hence Andriod 28, I am surprised this issue is open for so long with still no light at the end of the tunnel.

[jamesmcroft]

After landing here from Google after having the same issue, I thought I'd be here to find a solution for the problem.

Is this a breaking change in the Support Libraries for Xamarin? Or does it require a specific version of Xamarin.Android to work correctly?

Having this issue with Visual Studio 2017.

[Redth]

There's an easy way to skip this task entirely if it's causing you issues, just put this in your .csproj:

 <PropertyGroup>
      <XamarinAndroidSupportSkipVerifyVersions>true</XamarinAndroidSupportSkipVerifyVersions>
    </PropertyGroup>

[iashaik]

Updating all problematic NuGet Packages (in my case Firebase packages) to use the supported 28.0.0.3 version did resolve the issue.