msbuild /t:Install fails if adb server isn't running

[kdubau]

Steps to Reproduce

1. Make sure you have a device connected and trusted
2. Make sure Visual Studio is closed
3. Make sure adb server is not running, adb kill-server, or end it from task manger
4. Unzip the attached project Wat.zip
5. Run msbuild /t:Restore C:\path\to\Wat.csproj
6. Run msbuild /t:Install C:\path\to\Wat.csproj

Wat.zip

Expected Behavior

It should start adb and use the connected USB device to install the app.

Actual Behavior

It fails with the error:

"C:\Users\kywhi\Downloads\Wat\Wat\Wat\Wat.csproj" (Install target) (1) ->
(_Upload target) ->
  C:\Program Files (x86)\Microsoft Visual Studio\2019\Preview\MSBuild\Xamarin\Android\Xamarin.Android.Common.Debugging.
targets(624,2): error XA0010: adb is not running. System.AggregateException: One or more errors occurred. ---> System.A
ggregateException: One or more errors occurred. ---> System.Net.Sockets.SocketException: No connection could be made be
cause the target machine actively refused it 127.0.0.1:5037 [C:\Users\kywhi\Downloads\Wat\Wat\Wat\Wat.csproj]

Version Information

Microsoft Visual Studio Enterprise 2019 Int Preview
Version 16.2.0 Preview 4.0 [29020.217.d16.2stg]
VisualStudio.16.IntPreview/16.2.0-pre.4.0+29020.217.d16.2stg

Xamarin.Android SDK 9.4.0.34 (d16-2/7cce305)
Xamarin.Android Reference Assemblies and MSBuild support.
Mono: mono/mono@c6edaa62f94
Java.Interop: xamarin/java.interop/d16-2@b2b2610
LibZipSharp: grendello/LibZipSharp/d16-2@caa0c74
LibZip: nih-at/libzip@b95cf3f
ProGuard: xamarin/proguard@905836d
SQLite: xamarin/sqlite@8212a2d
Xamarin.Android Tools: xamarin/xamarin-android-tools/master@4f717b6

Log File

binlog.zip

[jonathanpeppers]

@dellis1972 I think it has always done this? The IDE starts adb, and the Install target does not.

Maybe it was done this way for performance reasons?

[dellis1972]

The adb server is generally started when a device is plugged in or an emulator is started. The IDE usually deals with this. Historically, we have NOT tried to check and start adb as part of the Install target because it would slow down fast deployment. It has just been assumed it would be running. Now can we improve the error messaging ? Certainly. We handle issue where a device is not present (but adb is running) so we should perhaps try to catch this error and provide a decent error message.

That said.. should we provide a way to start adb in a CI environment?