Support msbuild /t:restore;build gesture

[srivatsn]

From @onovotny on December 21, 2016 2:12

Splitting from dotnet/sdk#531

Today you have to explicitly do two commands for a proper build:

• msbuild /t:restore
• msbuild /t:build

It would be easier and more intuitive if the SDK could combine those to enable:
msbuild /t:restore;build, msbuild /t:restore;pack or even simply implicitly call restore (unless opted out with a variable?).

It's true that the build may have to re-evaluate itself after the restore since additional props/targets may be imported, but somehow this should be made to work.

Copied from original issue: dotnet/sdk#541

[srivatsn]

From @davidfowl on December 21, 2016 3:19

We've been discussing what it would take to treat restore like a build dependency so that it's fully incremental and does everything at the required times. That would eliminate the need for running more than a single command.

[emgarten]

This requires a change to MSBuild as @davidfowl mentioned.

An example of the issue today:

1. MSBuild evaluates all imports and properties
2. Restore downloads packages and adds .targets and .props files from the packages
3. MSBuild does not load these new targets/props
4. Build runs without package targets/props

It is unclear what work NuGet would actually need to do here, if any.

[zhili1208]

"msbuild /restore" work for this scenario

[clairernovotny]

Huh? This is not closed... the goal was that msbuild /t:restore was not an explicit step. It needs to be chainable with build, so msbuild /t:restore;build works at the same time. More importantly, Build should have Restore as a dependency.

[emgarten]

@onovotny I think you may have better luck filing this on msbuild with that explanation.

[clairernovotny]

I didn't file it here :) Can one of you move this to the right repo then using that tool you have?