feat: mark GitHub releases as prereleases for prerelease versions

docs/wiki/Configuration-Reference.md

@@ -96,6 +96,7 @@ Content entry paths and package-id keys are matched as globs (case-insensitive),
 | --- | --- | --- |
 | `Mode` | `None` | `None`, `LocalNuGet`, `NuGet`, or `GitHubRelease` |
 | `UploadArtifacts` | `false` | Upload every file in `Build:ArtifactsFolder` as GitHub release assets |
+| `MarkPrerelease` | `true` | Create the GitHub release as a prerelease when the package version is a prerelease (for example `2.0.0-prerelease.25`) |
 
 ## Example
 

docs/wiki/Pipeline-Modules.md

@@ -80,7 +80,7 @@ Moves the `.nupkg`/`.snupkg` files from `Build:ArtifactsFolder` into the local f
 
 Category `Release`. Depends on `PublishNuGetModule`, `ValidatePackModule`, and `VersionModule`. Skip condition: skipped unless `Release:Mode` is `NuGet` or `GitHubRelease` **and** a GitHub token resolves via `GitHub:GetGitHubToken()`.
 
-Creates a GitHub release with tag `v{version}` and `GenerateReleaseNotes = true`. When `Release:UploadArtifacts` is true, uploads every file in `Build:ArtifactsFolder` as a release asset — for Web projects this is the `<package-name>-<version>.zip` produced by `PackModule`. The tag must not already exist; callers gate release eligibility (the tool does not skip an existing tag itself).
+Creates a GitHub release with tag `v{version}` and `GenerateReleaseNotes = true`. Releases whose version is a prerelease (for example `2.0.0-prerelease.25`) are created as GitHub prereleases unless `Release:MarkPrerelease` is false, so prerelease builds are not presented as the latest stable release. When `Release:UploadArtifacts` is true, uploads every file in `Build:ArtifactsFolder` as a release asset — for Web projects this is the `<package-name>-<version>.zip` produced by `PackModule`. The tag must not already exist; callers gate release eligibility (the tool does not skip an existing tag itself).
 
 ## See also
 

src/src/Build/Modules/CreateGitHubReleaseModule.cs

@@ -55,14 +55,28 @@ CancellationToken cancellationToken
 			);
 		}
 
-		// Create a new release on GitHub with the specified tag and generate release notes
+		// Create a new release on GitHub with the specified tag and generate release notes.
+		// Prerelease versions are published as prereleases so they are not presented as the
+		// latest stable release.
+		var isPrerelease = releaseSettings.Value.ShouldMarkPrerelease(version);
 		var release = await context
 			.GitHub()
 			.Client.Repository.Release.Create(
 				repositoryId,
-				new NewRelease(tag) { Name = tag, GenerateReleaseNotes = true }
+				new NewRelease(tag)
+				{
+					Name = tag,
+					GenerateReleaseNotes = true,
+					Prerelease = isPrerelease,
+				}
 			);
 
+		context.Logger.LogInformation(
+			"Created GitHub release {Tag}{Prerelease}.",
+			tag,
+			isPrerelease ? " as a prerelease" : string.Empty
+		);
+
 		if (releaseSettings.Value.UploadArtifacts)
 		{
 			var artifactsFolder = buildSettings.Value.ArtifactsFolder;

src/src/Build/Settings/ReleaseSettings.cs

@@ -1,3 +1,5 @@
+using NuGet.Versioning;
+
 namespace Purview.Build.Settings;
 
 public sealed record ReleaseSettings
@@ -11,4 +13,22 @@ public sealed record ReleaseSettings
 	/// (for example .nupkg/.snupkg or .vsix) as release assets.
 	/// </summary>
 	public bool UploadArtifacts { get; init; }
+
+	/// <summary>
+	/// When true (the default), a GitHub release whose version is a prerelease (for example
+	/// <c>2.0.0-prerelease.25</c>) is created as a prerelease, so it is not presented as the latest
+	/// stable release. Set to false to publish prerelease versions as stable releases.
+	/// </summary>
+	public bool MarkPrerelease { get; init; } = true;
+
+	/// <summary>
+	/// Returns whether a release for <paramref name="version"/> should be created as a GitHub
+	/// prerelease.
+	/// </summary>
+	public bool ShouldMarkPrerelease(NuGetVersion version)
+	{
+		ArgumentNullException.ThrowIfNull(version);
+
+		return MarkPrerelease && version.IsPrerelease;
+	}
 }

src/src/Build/appsettings.json

@@ -47,6 +47,7 @@
 	},
 	"Release": {
 		"Mode": "None",
-		"UploadArtifacts": false
+		"UploadArtifacts": false,
+		"MarkPrerelease": true
 	}
 }

src/tests/Build.IntegrationTests/ReleaseSettingsTests.cs

@@ -0,0 +1,39 @@
+using NuGet.Versioning;
+using Purview.Build.Settings;
+
+namespace Purview.Build;
+
+public class ReleaseSettingsTests
+{
+	[Test]
+	public async Task ShouldMarkPrerelease_GivenPrereleaseVersionAndDefaults_ReturnsTrue()
+	{
+		ReleaseSettings settings = new();
+
+		await Assert.That(settings.ShouldMarkPrerelease(NuGetVersion.Parse("2.0.0-prerelease.25"))).IsTrue();
+	}
+
+	[Test]
+	public async Task ShouldMarkPrerelease_GivenStableVersionAndDefaults_ReturnsFalse()
+	{
+		ReleaseSettings settings = new();
+
+		await Assert.That(settings.ShouldMarkPrerelease(NuGetVersion.Parse("2.0.0"))).IsFalse();
+	}
+
+	[Test]
+	public async Task ShouldMarkPrerelease_GivenMarkPrereleaseDisabled_ReturnsFalse()
+	{
+		ReleaseSettings settings = new() { MarkPrerelease = false };
+
+		await Assert.That(settings.ShouldMarkPrerelease(NuGetVersion.Parse("2.0.0-prerelease.25"))).IsFalse();
+	}
+
+	[Test]
+	public async Task MarkPrerelease_GivenDefaults_IsTrue()
+	{
+		ReleaseSettings settings = new();
+
+		await Assert.That(settings.MarkPrerelease).IsTrue();
+	}
+}