Restrict partial evaluation to ProjectInstance - #14340
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The opt-in partial (stop-after-pass) evaluation feature was exposed on both Project and ProjectInstance. Project is mutable and cached by ProjectCollection, so a partial Project is a footgun: it either serves stale partial state from the cache or gets silently upgraded to a full evaluation (discarding the perf win) when handed to something that requires later passes. ProjectInstance is an uncached, read-only snapshot and is trap-proof, so partial evaluation now lives there exclusively. Changes: - Remove all partial-eval honoring from Project: the public EvaluationStage property, the ProjectImpl stage field/guards, the partial->Full upgrade blocks in ReevaluateIfNecessary/CreateProjectInstance, and the evaluationStage ctor parameters. Project factories now throw ArgumentException when a non-Full stage is requested via ProjectOptions (new OM_PartialEvaluationNotSupportedForProject resource + xlf entries). - Drop the now-dead cache upgrade-in-place logic in ProjectCollection.LoadProject. - Switch the -getProperty/-getItem (no-target) CLI path in XMake to ProjectInstance.FromFile, and log MSB4025 for pre-evaluation project load failures (Project logged these before throwing; ProjectInstance does not). - Clean up orphaned Project-based JSON item formatter overloads. - Point the partial-eval benchmark at ProjectInstance. - Update the partial-evaluation spec and unit tests accordingly. ProjectInstance retains full partial-evaluation support (EvaluationStage, member guards, OM_PartialEvaluationMemberUnavailable/CannotBuild). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 008efa7a-b4fc-4f33-9dc7-d37d3f0e93c3
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Pull request overview
Restricts partial (stop-after-pass) evaluation support to ProjectInstance only, removing/denying partial evaluation paths on mutable, ProjectCollection-cached Project to avoid stale cached partial state and hidden upgrade-to-full work.
Changes:
- MSBuild CLI
-getProperty/-getItemno-target path now evaluates viaProjectInstance.FromFileand updates JSON item formatting accordingly. Projectfactories reject non-FullProjectOptions.EvaluationStageandProjectCollection.LoadProjectdrops now-dead partial-upgrade cache logic.- Updates tests, benchmarks, resources/localization, and the partial-evaluation spec to reflect the
ProjectInstance-only model.
Show a summary per file
| File | Description |
|---|---|
| src/MSBuild/XMake.cs | Switches no-target -getProperty/-getItem evaluation to ProjectInstance and adjusts error surfacing and JSON item formatting calls. |
| src/MSBuild/JsonOutputFormatter.cs | Removes Project-based item JSON formatting overloads; keeps ProjectInstance path. |
| src/MSBuild.Benchmarks/PartialEvaluationBenchmark.cs | Updates benchmark to mirror CLI by loading via ProjectInstance. |
| src/Build/Resources/xlf/Strings.zh-Hant.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.zh-Hans.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.tr.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.ru.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.pt-BR.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.pl.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.ko.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.ja.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.it.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.fr.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.es.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.de.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/xlf/Strings.cs.xlf | Adds localized placeholder entry for OM_PartialEvaluationNotSupportedForProject. |
| src/Build/Resources/Strings.resx | Adds OM_PartialEvaluationNotSupportedForProject resource string. |
| src/Build/Definition/ProjectOptions.cs | Documents that partial stages are honored only for ProjectInstance, and Project factories throw. |
| src/Build/Definition/ProjectCollection.cs | Removes partial-eval upgrade-in-place logic from the loaded-project cache. |
| src/Build/Definition/Project.cs | Removes Project partial-eval plumbing/guards and adds up-front rejection for partial stages in Project factory methods. |
| src/Build.UnitTests/Evaluation/PartialEvaluation_Tests.cs | Reworks tests to validate Project factories reject partial stages and ProjectInstance retains behavior. |
| documentation/specs/proposed/partial-evaluation.md | Updates spec to explicitly scope partial evaluation to ProjectInstance and explains why Project does not support it. |
Copilot's findings
- Files reviewed: 22/22 changed files
- Comments generated: 2
- ThrowIfPartialEvaluationRequested now validates options for null up front, so the public Project.From* factories throw ArgumentNullException (not NullReferenceException) when passed null ProjectOptions. Added a covering test. - The -getProperty/-getItem invalid-project error path now prints ex.Message instead of ex.BaseMessage so the project file path is retained in the MSB4025 output, matching the prior Project-based behavior. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 008efa7a-b4fc-4f33-9dc7-d37d3f0e93c3
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Updated [Microsoft.Build.Utilities.Core](https://github.com/dotnet/msbuild) from 18.9.6 to 18.10.1. <details> <summary>Release notes</summary> _Sourced from [Microsoft.Build.Utilities.Core's releases](https://github.com/dotnet/msbuild/releases)._ ## 18.10.1 ## What's Changed * [vs16.11] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13103 * [vs17.12] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13796 * [vs17.8] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13902 * [vs17.11] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13903 * [vs17.12] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13909 * [vs17.12] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13986 * Add vs18.9 to merge-flow config; retire vs18.3 by @JanProvaznik in dotnet/msbuild#14214 * Bump labeler-cache-retention to use issue-labeler v2.1.0 by @jeffhandley in dotnet/msbuild#14171 * Bump main to 18.10.0 after vs18.9 snap by @JanProvaznik in dotnet/msbuild#14216 * Improve release skill: Phase 2 DARC rules, VMR backflow, deterministic baseline by @JanProvaznik in dotnet/msbuild#14220 * Determinize release: hardcode OptProf baseline + Phase 3.2 baseline resolver by @JanProvaznik in dotnet/msbuild#14222 * Serialize BuildRequestConfiguration.RequestedTargets to fix solution metaproject MSB4057 in parallel builds by @ViktorHofer in dotnet/msbuild#14223 * [main] Update dependencies from nuget/nuget.client by @dotnet-maestro[bot] in dotnet/msbuild#14203 * Core support for AbsolutePath/FileInfo/DirectoryInfo and ITaskItem<T> as task parameters by @baronfel in dotnet/msbuild#13971 * [main] Update dependencies from dotnet/roslyn by @dotnet-maestro[bot] in dotnet/msbuild#14206 * Fix existence cache kind poisoning by @AlesProkop in dotnet/msbuild#14249 * [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in dotnet/msbuild#14226 * Don't disable the MSBuild server for /mt builds when node reuse is off by @AR-May in dotnet/msbuild#14248 * Enhance expert reviewer guidelines with additional checks. by @AR-May in dotnet/msbuild#14255 * [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in dotnet/msbuild#14253 * [main] Update dependencies from dotnet/roslyn by @dotnet-maestro[bot] in dotnet/msbuild#14268 * [main] Update dependencies from nuget/nuget.client by @dotnet-maestro[bot] in dotnet/msbuild#14267 * Bump github/gh-aw-actions/setup from 0.81.6 to 0.82.2 by @dependabot[bot] in dotnet/msbuild#14266 * Avoid boxing the struct enumerator in PropertyDictionary<T>.GetEnumerator() by @nareshjo in dotnet/msbuild#14272 * Refresh copy marker when implementation output changes by @AlesProkop in dotnet/msbuild#14231 * Send task-host build process environment as delta by @OvesN in dotnet/msbuild#14126 * Add regression coverage for metadata newline preservation by @VolPlita in dotnet/msbuild#14261 * Fix EmbedInBinlog items with relative paths from child projects by @huulinhnguyen-dev in dotnet/msbuild#13990 * Stop requiring VersionPrefix updates in servicing - insert prerelease versions to VS by @ViktorHofer in dotnet/msbuild#14277 * Fix WriteLinesToFile rewriting unchanged file when custom encoding is used by @huulinhnguyen-dev in dotnet/msbuild#14146 * Enable trim/AOT analyzers for Microsoft.Build and clean up annotations by @JeremyKuhne in dotnet/msbuild#14064 * [automated] Merge branch 'vs18.9' => 'main' by @github-actions[bot] in dotnet/msbuild#14291 * Fix MicroBuild plugin feed URL to use allowed pkgs.dev.azure.com format by @AlesProkop in dotnet/msbuild#14295 * Pass ExcludeRestorePackageImports during restore to avoid redundant evaluations by @ViktorHofer with @Copilot in dotnet/msbuild#14274 * [vs18.7] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13988 * Adopt Clever Test Selection (CTS) as parallel, non-blocking PR pipeline by @jankratochvilcz in dotnet/msbuild#14212 * Harden exceptions when connecting to server by @JanProvaznik in dotnet/msbuild#14292 * Update MicrosoftBuildVersion in analyzer template by @github-actions[bot] in dotnet/msbuild#13886 * Fix MSBuild Server client dropping build result under WaitAny race (#14172) by @JanProvaznik in dotnet/msbuild#14251 * Partially revert #13660: remove NuGet RestoreTask transient TaskHost workaround by @JanProvaznik in dotnet/msbuild#14297 * Disable daily AI credits guardrail for Expert Code Review workflow by @JanProvaznik with @Copilot in dotnet/msbuild#14314 * Localized file check-in by OneLocBuild Task: Build definition ID 9434: Build ID 14614733 by @dotnet-bot in dotnet/msbuild#14246 * Add opt-in partial (stop-after-pass) project evaluation by @ViktorHofer in dotnet/msbuild#14290 * Use partial evaluation for -getProperty/-getItem without a target by @ViktorHofer in dotnet/msbuild#14296 * [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in dotnet/msbuild#14324 * [main] Update dependencies from dotnet/roslyn by @dotnet-maestro[bot] in dotnet/msbuild#14333 * [main] Update dependencies from nuget/nuget.client by @dotnet-maestro[bot] in dotnet/msbuild#14330 * Bump github/gh-aw-actions/setup from 0.82.2 to 0.82.8 by @dependabot[bot] in dotnet/msbuild#14328 * Restrict partial evaluation to ProjectInstance by @ViktorHofer in dotnet/msbuild#14340 ... (truncated) Commits viewable in [compare view](dotnet/msbuild@v18.9.6...v18.10.1). </details> [](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores) Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting `@dependabot rebase`. [//]: # (dependabot-automerge-start) [//]: # (dependabot-automerge-end) --- <details> <summary>Dependabot commands and options</summary> <br /> You can trigger Dependabot actions by commenting on this PR: - `@dependabot rebase` will rebase this PR - `@dependabot recreate` will recreate this PR, overwriting any edits that have been made to it - `@dependabot show <dependency name> ignore conditions` will show all of the ignore conditions of the specified dependency - `@dependabot ignore this major version` will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this minor version` will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this dependency` will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself) </details> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
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Summary
Partial (stop-after-pass) evaluation was exposed on both
ProjectandProjectInstance. This PR restricts it toProjectInstanceonly.Projectis mutable and cached byProjectCollection, which makes a partially-evaluatedProjecta footgun:Projectcan be handed back to a caller expecting a full evaluation, serving stale partial state, orProjectInstanceis an uncached, read-only evaluation snapshot with none of these traps, so partial evaluation now lives there exclusively.Changes
Project: removed all partial-eval honoring — the publicEvaluationStageproperty, theProjectImplstage field + member guards, the partial→Full upgrade blocks inReevaluateIfNecessary/CreateProjectInstance, and theevaluationStageconstructor parameters.Project.FromFile/FromProjectRootElement/FromXmlReadernow throwArgumentExceptionwhen a non-Fullstage is requested viaProjectOptions(newOM_PartialEvaluationNotSupportedForProjectresource + xlf entries).ProjectCollection.LoadProject: dropped the now-dead partial cache upgrade-in-place logic.XMake(-getProperty/-getItem, no-target path): switched fromProject.FromFiletoProjectInstance.FromFile.ProjectInstancedoes not log pre-evaluation project-load failures (malformed XML) the wayProjectdid, so the catch block now surfacesMSB4025in canonical format (guarded byHasBeenLoggedto avoid double-logging genuine evaluation errors).JsonOutputFormatter: removed orphanedProject-based item formatter overloads.PartialEvaluationBenchmarknow usesProjectInstance.ProjectInstanceretains full partial-evaluation support (EvaluationStage, member guards,OM_PartialEvaluationMemberUnavailable/OM_PartialEvaluationCannotBuild).Testing
PartialEvaluation_Tests(Engine.UnitTests): 13/13 pass.-getProperty/-getItemCLI tests + fullXMakeAppTests(CommandLine.UnitTests): pass (incl.GetPropertyWithInvalidProjectThrowsInvalidProjectFileExceptionNotInternalError, which verifiesMSB4025is still emitted).