Move LongPath check to MSBuild target #68217
Conversation
The Roslyn repository effectively depends on having long paths enabled at this point. Between NuGet and the VSSDK, both outside our control, our repository runs right up against `MAX_PATH` limits even with a very short user name. A user name of any significant length will quickly run into issues in our repo. The repository already warns about long path support, and has for some time, but it does so in command line builds. That was a fine experience when it was added as long path support was new and was only needed in a few cases. Now though it's effectivtely needed for everyone so need to give it more visibility by elevating it to an MSBuild warning. This warning is _deliberately_ not configurable. Having long paths disabled at this point means your inner loop dev experience is broken in strange, hard to diagnose ways.
dotnet-issue-labeler
bot
added
Area-Infrastructure
untriaged
| @@ -154,6 +154,14 @@ | |||
| Condition="$(_VersionComparisonResult) < 0"/> | |||
| </Target> | |||
|
|
|||
| <Target Name="_CheckLongPathSupport" BeforeTargets="BeforeBuild" Condition="'$(MSBuildRuntimeType)' == 'Full'"> | |||
There was a problem hiding this comment.
💭 Should this be an OS check instead?
| <_RoslynLongPathsEnabled>$([MSBuild]::GetRegistryValueFromView('HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\FileSystem', 'LongPathsEnabled', null, RegistryView.Registry64, RegistryView.Registry32))</_RoslynLongPathsEnabled> | ||
| </PropertyGroup> | ||
|
|
||
| <Warning Condition="'$(_RoslynLongPathsEnabled)' != '1'" Text="Long paths are required for this project. Please run eng\enable-long-paths.reg" /> |
There was a problem hiding this comment.
💡 Consider assigning Code here as well
There was a problem hiding this comment.
Can you elaborate on that? Not quite sure what that means.
There was a problem hiding this comment.
something like
<Warning Code="JARED001" Condition="'$(_RoslynLongPathsEnabled)' != '1'" Text="Long paths are required for this project. Please run eng\enable-long-paths.reg" />
personally I don't see particular value unless you're going to write help content for it or expect people to suppress it
There was a problem hiding this comment.
Yeah I specifically don't want this warning to be suppressible.
|
For my own education - if this is merged, what would the experience now be for those of us who reported issues with longpath? Would the error change and become more meaningful? |
|
@carlossanlop This won't automatically apply to other repositories, but it may help establish a standard practice for dealing with this situation. |
ghost
added this to the 
The Roslyn repository effectively depends on having long paths enabled at this point. Between NuGet and the VSSDK, both outside our control, our repository runs right up against
MAX_PATHlimits even with a very short user name. A user name of any significant length will quickly run into issues in our repo.The repository already warns about long path support, and has for some time, but it does so in command line builds. That was a fine experience when it was added as long path support was new and was only needed in a few cases. Now though it's effectivtely needed for everyone so need to give it more visibility by elevating it to an MSBuild warning.
This warning is deliberately not configurable. Having long paths disabled at this point means your inner loop dev experience is broken in strange, hard to diagnose ways.