Dotnet publish no-build switch disappeared

[hongdai]

Steps to reproduce

Dotnet publish -no-build

Expected behavior

It is supported

Actual behavior

No longer supported

Environment data

dotnet --info output:

This is a useful switch. We would like to understand why it's removed and if there is a replacement.

[livarcocc]

@dsplaisted @nguerrera @eerhardt Is there a way to trigger a publish without build?

[TheRealPiotrP]

@hongdai It would be useful if you can share how you used this flag. I think there was some debate about whether it is still useful.

[eerhardt]

It would be useful if you can share how you used this flag

Agreed. Getting all the use cases for why this switch is useful helps us understand whether to put it back or not.

One of the use cases I've recently encountered was the F# team (specifically @KevinRansom) was using this switch to publish a project's references, but he didn't want the project's output (its .dll) published. The replacement in that case is to add the MSBuild property <CopyBuildOutputToPublishDirectory>false</CopyBuildOutputToPublishDirectory> in your .csproj. That way, the current project's .dll isn't published.

FYI - @livarcocc and @piotrpMSFT, we could use this switch in the dotnet/cli ourselves in https://github.com/dotnet/cli/blob/rel/1.0.0/src/redist/redist.csproj. Then we wouldn't need to delete the redist.dll after publish, like we are currently doing.

[codito]

It will be great to have --no-build supported.

We do the following in vstest repo:

1. Build the sln file (all product, tests are built)
2. Publish only the product projects
3. Zip the published project for distribution

In step 2, all the product dlls are built again. Depending on the number projects published, some of the common dependencies could be built multiple times.

Update: our build process had a race condition on resources files which was slowing down the process. As @eerhardt notes below, msbuild incremental build does kick in, it is not a significant overhead for us now.

[eerhardt]

In step 2, all the product dlls are built again.

Why is incremental building not kicking in? MSBuild knows if a project is already built, and doesn't need to build it again.

[hongdai]

@piotrpMSFT We used to have our own publish target and run in AfterBuild. Without no-build switch, the publish target will invoke a build and cause a infinite loop, unless we add a condition.

dotnet pack still supports no-build switch. I think the usage should be similar.

[atanasa]

+1

As I see it, there should be an option to have the output of a build be the output of what you call "publish". I'd say that this should be the default behavior but that is debatable. As far as I understand it from reading the issues and documentation, this discrepancy is a workaround to speed up the build time of console apps (e.g. use the nuget cache to save on checksum calculations?!).

.Net is used for more than console apps and as such that workaround is not applicable to hosts different than dotnet run. For those cases, the actual dependencies are needed as part of the build output so it is runnable.

For such cases, I've managed to make dotnet publish output what is the real build output. To have it integrated with the VS Run command, I'd like to have the MSBuild Build target run the Publish target logic. This leads me to the infinite loop that @hongdai is talking about.

For me the no-build switch is a workaround. Ideally I would like you to support the case where the output of the build contains all the required runtime dependencies.

[eamodio]

Same issue here -- Why wasn't this BREAKING CHANGE announced on the announcement repo? I've just converted all our stuff to csproj and now this broke our whole ci/azure setup.

We have 3 deployments setup on AppVeyor for a single solution, so we have 3 configurations that do the following:

1. Build all the specific projects for this config
2. Run all the specific tests for this config
3. Publish to folder to be deployed by AppVeyor to Azure

[eerhardt]

@eamodio - same question as above - Why is incremental building not kicking in?

[eamodio]

Let's say it is kicking in (which I think it is) -- just the fact the it has to run msbuild, scan for the project(s), see if they need building, etc -- all takes time; time I don't want to be waiting for my CI to finish. For example, on one of my projects it takes about 23s to build it the first time and then 9s to build it the second time (the one that used to be skipped). Yeah, 9s isn't that long in the scheme of things, but it isn't nothing either.

Also, given this flag is seemingly just a simple -- don't run msbuild -- I don't understand why it is so desirable to not support it?

[dasMulli]

I think this is caused by the current situations that large package graphs (netstandard.library, m.n.app) slow down msbuild projects which is causing project references to slow down linear (1 project 1 sec, 10 projects 10 sec) and has been discussed in https://github.com/dotnet/cli/issues/5918, #1116, dotnet/msbuild#1276 and maybe even more.

Even if build targets are avoided for publish, I believe RunResolvePackageDependencies and ResolveAssemblyReferences would still need to be run to determine the proper publish output (I might be wrong) - and those are the targets that cause the slow incremental builds.

[eerhardt]

Also, given this flag is seemingly just a simple -- don't run msbuild -- I don't understand why it is so desirable to not support it?

@dasMulli hit the nail on the head.

What does --no-build mean? In reality in project.json world, it really meant something closer to --no-compile. But the Build target in MSBuild does so much more than just Compile your source code.

• It resolves references
• It resolves NuGet assets (managed and native libraries, content files, even pre-processed content files)
• It gathers your project's Content files that need to be copied to the output

Doing a Publish without the things that happen during the Build target in MSBuild is almost pointless. What do you expect to have happened?

Another thing to understand is that dotnet publish really means "run the Publish MSBuild target". So it obviously isn't as simple as "don't run msbuild", since you can't run the Publish target without MSBuild.

So the reason there is push back to supporting it is because it isn't clear what the option is supposed to do/mean. And once we settle on a definition, the next decision to make is - is the scenario we are enabling a high-priority scenario that many customers need?

[eamodio]

From that description why wouldn't --no-build mean don't run the Build target and only run the Publish target. Because if you've already run it without the --no-build flag then the Build target has already been run -- so everything is all prepared for the Publish target?

[eerhardt]

Like @dasMulli says above, there are shared targets between Build and Publish that will still need to be executed when just executing Publish. And the savings above and beyond an incremental build is usually negligible.

For example, on one of my projects it takes about 23s to build it the first time and then 9s to build it the second time (the one that used to be skipped). Yeah, 9s isn't that long in the scheme of things, but it isn't nothing either.

If you are interested in tracking down why the 2nd time is taking 9s, you can pass /v:diag into both dotnet build and dotnet publish. This will print out a lot of information (you probably want to pipe it to a file), but what you are interested in comes at the end. There is a table that shows where all the time is being spent in the build. For example, here is the table of publishing an ASP.NET 2.0 app on my local machine:

First Time

Project Performance Summary:
     6806 ms  F:\DotNetTest\TestWeb\TestWeb.csproj       1 calls
               6806 ms  Publish                                    1 calls

Target Performance Summary:
        0 ms  _DotNetCLIPrePublish                       1 calls
        0 ms  ComputeAndCopyFilesToPublishDirectory      1 calls
        0 ms  BeforeResGen                               1 calls
        0 ms  PrepareResourceNames                       1 calls
        0 ms  _DotNetCLIPostPublish                      1 calls
        0 ms  ResGen                                     1 calls
        0 ms  AfterBuild                                 1 calls
        0 ms  GetFrameworkPaths                          1 calls
        0 ms  ResolveReferences                          1 calls
        0 ms  GetReferenceAssemblyPaths                  1 calls
        0 ms  PrepareResources                           1 calls
        0 ms  _AspNetCoreProjectSystemPrePublish         1 calls
        0 ms  BeforeBuild                                1 calls
        0 ms  Compile                                    1 calls
        0 ms  AfterResGen                                1 calls
        0 ms  SetWin32ManifestProperties                 1 calls
        0 ms  CreateCustomManifestResourceNames          1 calls
        0 ms  GenerateUserSecretsAttribute               1 calls
        0 ms  CoreBuild                                  1 calls
        0 ms  GenerateAssemblyInfo                       1 calls
        0 ms  BeforePublish                              1 calls
        0 ms  _AspNetCoreProjectSystemPostPublish        1 calls
        0 ms  AfterPublish                               1 calls
        0 ms  _CopySourceItemsToOutputDirectory          1 calls
        0 ms  CreateSatelliteAssemblies                  1 calls
        0 ms  AfterCompile                               1 calls
        0 ms  PrepareForRun                              1 calls
        0 ms  AfterResolveReferences                     1 calls
        0 ms  InjectReference_efa7ce74-36bd-481a-bac0-42e316fc1d57   1 calls
        0 ms  IncludeTransitiveProjectReferences         1 calls
        0 ms  InjectReference_095e2d6d-4484-4c4e-b23a-d4bd8983312a   1 calls
        0 ms  BeforeCompile                              1 calls
        0 ms  BeforeResolveReferences                    1 calls
        0 ms  Build                                      1 calls
        0 ms  CopyFilesToPublishDirectory                1 calls
        0 ms  PrepareProjectReferences                   1 calls
        0 ms  _DefaultMicrosoftNETPlatformLibrary        1 calls
        0 ms  ResolvePackageDependenciesForBuild         1 calls
        0 ms  ResolveSDKReferences                       1 calls
        0 ms  _SetTargetFrameworkMonikerAttribute        1 calls
        0 ms  ResolveLockFileAnalyzers                   1 calls
        0 ms  BuildOnlySettings                          1 calls
        0 ms  PublishWithAspNetCoreTargetManifest        1 calls
        0 ms  ComputePrivateAssetsPackageReferences      1 calls
        0 ms  ExpandSDKReferences                        1 calls
        0 ms  GetInstalledSDKLocations                   1 calls
        0 ms  GetTargetPath                              1 calls
        0 ms  InjectReference_324b1a06-f466-4b33-a9b7-baf91ae299f2   1 calls
        0 ms  ComputeDependencyFileCompilerOptions       1 calls
        0 ms  _CheckForUnsupportedSelfContained          1 calls
        0 ms  _ComputeNetPublishAssets                   1 calls
        0 ms  _GenerateRunCommandFile                    1 calls
        0 ms  _SplitProjectReferencesByFileExistence     1 calls
        0 ms  _GenerateCompileInputs                     1 calls
        0 ms  CoreResGen                                 1 calls
        0 ms  _DetermineProjectType                      1 calls
        0 ms  Publish                                    1 calls
        0 ms  _InitPublishIntermediateOutputPath         1 calls
        0 ms  _InitProjectCapabilityProperties           1 calls
        0 ms  _CheckForCompileOutputs                    1 calls
        0 ms  PrepareForPublish                          1 calls
        0 ms  _GenerateEFSQLScripts                      1 calls
        0 ms  _GenerateSatelliteAssemblyInputs           1 calls
        0 ms  _ComputeLockFileFrameworks                 1 calls
        0 ms  _TransformAppSettings                      1 calls
        0 ms  ResolveProjectReferences                   1 calls
        1 ms  _ComputeNETCoreBuildOutputFiles            1 calls
        1 ms  SplitResourcesByCulture                    1 calls
        1 ms  _SetEmbeddedWin32ManifestProperties        1 calls
        1 ms  ComputeFilesToPublish                      1 calls
        1 ms  GeneratePublishRuntimeConfigurationFile    1 calls
        1 ms  GetAssemblyVersion                         1 calls
        1 ms  GetCopyToOutputDirectoryItems              1 calls
        2 ms  DefaultCopyToPublishDirectoryMetadata      1 calls
        2 ms  _HandlePublishFileConflicts                1 calls
        2 ms  IncrementalClean                           1 calls
        2 ms  AssignTargetPaths                          1 calls
        2 ms  GenerateTargetFrameworkMonikerAttribute    1 calls
        2 ms  _ComputeCopyToPublishDirectoryItems        1 calls
        2 ms  GetCopyToPublishDirectoryItems             1 calls
        2 ms  _ComputeLockFileAnalyzers                  1 calls
        3 ms  CoreGenerateUserSecretsAttribute           1 calls
        3 ms  _ComputeActiveTFMFileDependencies          1 calls
        4 ms  _GetProjectReferenceTargetFrameworkProperties   1 calls
        4 ms  PrepareForBuild                            1 calls
        4 ms  _ComputeTransitiveProjectReferences        1 calls
        4 ms  _CheckForInvalidConfigurationAndPlatform   1 calls
        4 ms  CheckForDuplicateItems                     1 calls
        5 ms  _ComputeTFMOnlyFileDependencies            1 calls
        5 ms  CopyFilesToOutputDirectory                 1 calls
        6 ms  CoreGenerateAssemblyInfo                   1 calls
        6 ms  _CopyOutOfDateSourceItemsToOutputDirectory   1 calls
        6 ms  _ComputeActiveTFMPackageDependencies       1 calls
        7 ms  _CheckForUnsupportedTargetFramework        1 calls
       15 ms  CheckForImplicitPackageReferenceOverrides   1 calls
       19 ms  _TransformWebConfig                        1 calls
       22 ms  _ComputeResolvedFilesToPublishTypes        1 calls
       24 ms  RunResolvePublishAssemblies                1 calls
       26 ms  _GenerateCompileDependencyCache            1 calls
       27 ms  _CleanGetCurrentAndPriorFileWrites         1 calls
       30 ms  _IncludePrePublishGeneratedContent         1 calls
       40 ms  ComputeRefAssembliesToPublish              1 calls
       62 ms  _CopyResolvedFilesToPublishPreserveNewest   1 calls
       64 ms  GenerateBuildRuntimeConfigurationFiles     1 calls
       74 ms  _ComputeLockFileReferences                 1 calls
       81 ms  GeneratePublishDependencyFile              1 calls
       82 ms  ResolveLockFileReferences                  1 calls
       87 ms  RunProduceContentAssets                    1 calls
      148 ms  GenerateBuildDependencyFile                1 calls
      244 ms  _ComputeLockFileCopyLocal                  1 calls
      247 ms  _HandlePackageFileConflicts                1 calls
      249 ms  _CopyResolvedFilesToPublishAlways          1 calls
      276 ms  RunResolvePackageDependencies              1 calls
     1166 ms  CoreCompile                                1 calls
     3721 ms  ResolveAssemblyReferences                  1 calls

Task Performance Summary:
        0 ms  Delete                                     1 calls
        0 ms  ReadLinesFromFile                          1 calls
        0 ms  AssignCulture                              1 calls
        0 ms  RemoveDuplicates                           2 calls
        0 ms  GetFrameworkPath                           1 calls
        1 ms  FindAppConfigFile                          1 calls
        1 ms  FindUnderPath                              5 calls
        1 ms  MSBuild                                    1 calls
        1 ms  GetAssemblyVersion                         1 calls
        1 ms  Message                                    4 calls
        2 ms  AssignTargetPath                           6 calls
        2 ms  WriteLinesToFile                           2 calls
        3 ms  MakeDir                                    2 calls
        4 ms  CheckForDuplicateItems                     3 calls
        7 ms  CheckForImplicitPackageReferenceOverrides   1 calls
        8 ms  WriteCodeFragment                          2 calls
       10 ms  Hash                                       1 calls
       17 ms  TransformWebConfig                         1 calls
       18 ms  ProduceContentAssets                       1 calls
       22 ms  ConvertToAbsolutePath                      2 calls
       24 ms  ResolvePublishAssemblies                   1 calls
       64 ms  GenerateRuntimeConfigurationFiles          2 calls
      144 ms  ResolvePackageFileConflicts                2 calls
      229 ms  GenerateDepsFile                           2 calls
      274 ms  ResolvePackageDependencies                 1 calls
      316 ms  Copy                                       5 calls
     1164 ms  Csc                                        1 calls
     3719 ms  ResolveAssemblyReference                   1 calls

Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:00:07.19

Second Time

Project Performance Summary:
     5923 ms  F:\DotNetTest\TestWeb\TestWeb.csproj       1 calls
               5923 ms  Publish                                    1 calls

Target Performance Summary:
        0 ms  ResGen                                     1 calls
        0 ms  BeforeResGen                               1 calls
        0 ms  PrepareResourceNames                       1 calls
        0 ms  ResolveReferences                          1 calls
        0 ms  Compile                                    1 calls
        0 ms  _DotNetCLIPostPublish                      1 calls
        0 ms  _DotNetCLIPrePublish                       1 calls
        0 ms  ComputeAndCopyFilesToPublishDirectory      1 calls
        0 ms  _AspNetCoreProjectSystemPrePublish         1 calls
        0 ms  AfterBuild                                 1 calls
        0 ms  GetFrameworkPaths                          1 calls
        0 ms  PrepareResources                           1 calls
        0 ms  AfterResGen                                1 calls
        0 ms  SetWin32ManifestProperties                 1 calls
        0 ms  BeforeBuild                                1 calls
        0 ms  PrepareProjectReferences                   1 calls
        0 ms  CreateSatelliteAssemblies                  1 calls
        0 ms  BeforePublish                              1 calls
        0 ms  CreateCustomManifestResourceNames          1 calls
        0 ms  GenerateUserSecretsAttribute               1 calls
        0 ms  BeforeCompile                              1 calls
        0 ms  CoreBuild                                  1 calls
        0 ms  AfterCompile                               1 calls
        0 ms  AfterResolveReferences                     1 calls
        0 ms  GenerateAssemblyInfo                       1 calls
        0 ms  CopyFilesToPublishDirectory                1 calls
        0 ms  _CopySourceItemsToOutputDirectory          1 calls
        0 ms  ResolvePackageDependenciesForBuild         1 calls
        0 ms  InjectReference_efa7ce74-36bd-481a-bac0-42e316fc1d57   1 calls
        0 ms  Build                                      1 calls
        0 ms  BuildOnlySettings                          1 calls
        0 ms  GetReferenceAssemblyPaths                  1 calls
        0 ms  _AspNetCoreProjectSystemPostPublish        1 calls
        0 ms  AfterPublish                               1 calls
        0 ms  BeforeResolveReferences                    1 calls
        0 ms  PrepareForRun                              1 calls
        0 ms  IncludeTransitiveProjectReferences         1 calls
        0 ms  ExpandSDKReferences                        1 calls
        0 ms  ResolveLockFileAnalyzers                   1 calls
        0 ms  _DefaultMicrosoftNETPlatformLibrary        1 calls
        0 ms  InjectReference_095e2d6d-4484-4c4e-b23a-d4bd8983312a   1 calls
        0 ms  _SetTargetFrameworkMonikerAttribute        1 calls
        0 ms  PublishWithAspNetCoreTargetManifest        1 calls
        0 ms  ComputePrivateAssetsPackageReferences      1 calls
        0 ms  ResolveSDKReferences                       1 calls
        0 ms  ComputeDependencyFileCompilerOptions       1 calls
        0 ms  _CheckForUnsupportedSelfContained          1 calls
        0 ms  _ComputeNetPublishAssets                   1 calls
        0 ms  GetTargetPath                              1 calls
        0 ms  _SplitProjectReferencesByFileExistence     1 calls
        0 ms  PrepareForPublish                          1 calls
        0 ms  _GenerateRunCommandFile                    1 calls
        0 ms  GetInstalledSDKLocations                   1 calls
        0 ms  CoreResGen                                 1 calls
        0 ms  InjectReference_324b1a06-f466-4b33-a9b7-baf91ae299f2   1 calls
        0 ms  _DetermineProjectType                      1 calls
        0 ms  _CheckForCompileOutputs                    1 calls
        0 ms  _InitProjectCapabilityProperties           1 calls
        0 ms  _GenerateSatelliteAssemblyInputs           1 calls
        0 ms  GenerateBuildDependencyFile                1 calls
        0 ms  _GenerateCompileInputs                     1 calls
        0 ms  _InitPublishIntermediateOutputPath         1 calls
        0 ms  Publish                                    1 calls
        0 ms  ResolveProjectReferences                   1 calls
        0 ms  _GenerateEFSQLScripts                      1 calls
        0 ms  _ComputeLockFileFrameworks                 1 calls
        0 ms  _TransformAppSettings                      1 calls
        1 ms  _ComputeNETCoreBuildOutputFiles            1 calls
        1 ms  SplitResourcesByCulture                    1 calls
        1 ms  IncrementalClean                           1 calls
        1 ms  _SetEmbeddedWin32ManifestProperties        1 calls
        1 ms  DefaultCopyToPublishDirectoryMetadata      1 calls
        1 ms  GetCopyToOutputDirectoryItems              1 calls
        1 ms  _HandlePublishFileConflicts                1 calls
        1 ms  GeneratePublishRuntimeConfigurationFile    1 calls
        2 ms  CoreGenerateUserSecretsAttribute           1 calls
        2 ms  ComputeFilesToPublish                      1 calls
        2 ms  CoreGenerateAssemblyInfo                   1 calls
        2 ms  CopyFilesToOutputDirectory                 1 calls
        2 ms  _ComputeLockFileAnalyzers                  1 calls
        2 ms  AssignTargetPaths                          1 calls
        2 ms  GenerateTargetFrameworkMonikerAttribute    1 calls
        2 ms  GetAssemblyVersion                         1 calls
        3 ms  PrepareForBuild                            1 calls
        3 ms  _GetProjectReferenceTargetFrameworkProperties   1 calls
        3 ms  _ComputeActiveTFMFileDependencies          1 calls
        3 ms  _ComputeCopyToPublishDirectoryItems        1 calls
        3 ms  CheckForDuplicateItems                     1 calls
        3 ms  GetCopyToPublishDirectoryItems             1 calls
        4 ms  _ComputeTFMOnlyFileDependencies            1 calls
        4 ms  _CheckForInvalidConfigurationAndPlatform   1 calls
        4 ms  _ComputeTransitiveProjectReferences        1 calls
        6 ms  _ComputeActiveTFMPackageDependencies       1 calls
        8 ms  _CheckForUnsupportedTargetFramework        1 calls
       13 ms  CheckForImplicitPackageReferenceOverrides   1 calls
       14 ms  CoreCompile                                1 calls
       16 ms  _TransformWebConfig                        1 calls
       16 ms  _ComputeResolvedFilesToPublishTypes        1 calls
       24 ms  _CleanGetCurrentAndPriorFileWrites         1 calls
       25 ms  RunResolvePublishAssemblies                1 calls
       36 ms  _CopyOutOfDateSourceItemsToOutputDirectory   1 calls
       41 ms  ComputeRefAssembliesToPublish              1 calls
       50 ms  _GenerateCompileDependencyCache            1 calls
       72 ms  _IncludePrePublishGeneratedContent         1 calls
       72 ms  _ComputeLockFileReferences                 1 calls
       80 ms  GenerateBuildRuntimeConfigurationFiles     1 calls
       83 ms  ResolveLockFileReferences                  1 calls
       86 ms  RunProduceContentAssets                    1 calls
      159 ms  GeneratePublishDependencyFile              1 calls
      202 ms  _CopyResolvedFilesToPublishAlways          1 calls
      228 ms  _HandlePackageFileConflicts                1 calls
      236 ms  _ComputeLockFileCopyLocal                  1 calls
      273 ms  _CopyResolvedFilesToPublishPreserveNewest   1 calls
      275 ms  RunResolvePackageDependencies              1 calls
     3835 ms  ResolveAssemblyReferences                  1 calls

Task Performance Summary:
        0 ms  Delete                                     1 calls
        0 ms  AssignCulture                              1 calls
        0 ms  RemoveDuplicates                           2 calls
        1 ms  GetFrameworkPath                           1 calls
        1 ms  FindAppConfigFile                          1 calls
        1 ms  ReadLinesFromFile                          1 calls
        1 ms  MSBuild                                    1 calls
        1 ms  FindUnderPath                              5 calls
        1 ms  WriteLinesToFile                           1 calls
        1 ms  Message                                    4 calls
        2 ms  MakeDir                                    2 calls
        2 ms  AssignTargetPath                           6 calls
        2 ms  GetAssemblyVersion                         1 calls
        3 ms  CheckForDuplicateItems                     3 calls
        6 ms  CheckForImplicitPackageReferenceOverrides   1 calls
       10 ms  Hash                                       1 calls
       14 ms  TransformWebConfig                         1 calls
       18 ms  ProduceContentAssets                       1 calls
       20 ms  ConvertToAbsolutePath                      2 calls
       25 ms  ResolvePublishAssemblies                   1 calls
       81 ms  GenerateRuntimeConfigurationFiles          2 calls
      143 ms  ResolvePackageFileConflicts                2 calls
      159 ms  GenerateDepsFile                           1 calls
      204 ms  Copy                                       3 calls
      268 ms  ResolvePackageDependencies                 1 calls
     3833 ms  ResolveAssemblyReference                   1 calls

Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:00:06.18

As you can see, CSC is only taking a little over 1s the first time. However, even in the 2nd time ResolveAssemblyReference is taking ~65% of the time (3835 ms / 5923 ms). As I asked above, do you expect that when you dotnet publish --no-build that you shouldn't get any referenced assemblies copied to your output directory?

(Now granted, we probably have some sort of perf bug in ResolveAssemblyReference, but that is a different discussion.)

Anyway, I'd be interested in learning what you find is taking 9s on your 2nd build. I'm sure you would be too 😉.

[eamodio]

Thanks for the information! I will try that out and see what the bottleneck is.

As for the ResolveAssemblyReference -- If that isn't done as part of the Build task, then I would expect it to be done, but if it isn't done as part of the Build task, then I would expect it to be done.

Basically I just want to avoid doing duplicate work.