validate-samples

Testing & Quality

Build and validate SkiaSharp sample projects using CI-produced NuGet packages. Downloads the latest CI artifacts, detects the preview version, and runs the samples cake target to verify all samples compile correctly. Triggers: "validate samples", "build samples", "test samples", "check samples build", "run samples", "do the samples build", "samples CI", "verify sample builds". Also use when asked to check if samples work after a code change, or when investigating sample build failures. Use this skill proactively whenever the user mentions building, testing, or validating any SkiaSharp sample project.

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Validate Samples

Automates the workflow for building SkiaSharp samples against CI-produced NuGet packages. The samples use package references (not project references) when built through the cake target, so they need downloadable NuGet packages.

When to Use

After making changes to samples and wanting to verify they build
When CI reports sample build failures and you need to reproduce locally
When validating that a new SkiaSharp release doesn't break samples
After merging changes that affect sample project files or dependencies

Workflow

Step 1: Clear cached packages

rm -r -fo externals/package_cache/skiasharp*, externals/package_cache/harfbuzzsharp*

If you suspect deeper caching issues, also clear the global NuGet cache:

dotnet nuget locals all --clear

Step 2: Download CI packages

Downloads the latest NuGet packages from the CI feed into output/nugets/. This target clears ./output/ first.

dotnet cake --target=docs-download-output

To download from a specific source instead of the latest main build:

# From a PR
dotnet cake --target=docs-download-output --previewLabel=pr.3553

# From a specific branch
dotnet cake --target=docs-download-output --gitBranch=release/3.119.4

# From a specific commit
dotnet cake --target=docs-download-output --gitSha=abc123def456

Step 3: Detect the preview version

Run the detection script — it prints the preview label and build number extracted from the downloaded nupkg filenames:

pwsh .agents/skills/validate-samples/scripts/detect-preview-version.ps1

Output:

Found: SkiaSharp.3.119.4-preview.0.76.nupkg
Preview label: preview.0
Build number:  76
Full suffix:   preview.0.76

Parse Preview label and Build number from the output for the next step.

Step 4: Build samples

dotnet cake --target=samples --previewLabel=<PREVIEW_LABEL> --buildNumber=<BUILD_NUMBER>

To build a single sample, add --sample=<name>:

dotnet cake --target=samples --previewLabel=<PREVIEW_LABEL> --buildNumber=<BUILD_NUMBER> --sample=Blazor

Troubleshooting

Stale packages after repeated runs

rm -r -fo externals/package_cache/skiasharp*, externals/package_cache/harfbuzzsharp*
dotnet nuget locals all --clear

Platform-specific samples not building

Some platforms are disabled by default:

# Pass these MSBuild properties to enable optional platforms
-p:IsNetTVOSSupported=true
-p:IsNetTizenSupported=true
-p:IsNetMacOSSupported=true

WinUI XAML compiler crash on .NET 10

May need a newer Microsoft.WindowsAppSDK version.

"The local source 'packages' doesn't exist" (Docker samples)

Docker samples are built via run.ps1 inside Docker, not dotnet build. The samples-prepare target copies nupkgs there automatically.