ReleaseManager: do not reset VersionHeightOffset if equals to -1

Author: Dmitry Zhelnin

src/NerdBank.GitVersioning/ReleaseManager.cs

@@ -280,7 +280,7 @@ private void UpdateVersion(LibGit2Context context, SemanticVersion oldVersion, S
 
         if (!EqualityComparer<SemanticVersion>.Default.Equals(versionOptions.Version, newVersion))
         {
-            if (versionOptions.VersionHeightPosition.HasValue && SemanticVersion.WillVersionChangeResetVersionHeight(versionOptions.Version, newVersion, versionOptions.VersionHeightPosition.Value))
+            if (versionOptions.VersionHeightOffset != -1 && versionOptions.VersionHeightPosition.HasValue && SemanticVersion.WillVersionChangeResetVersionHeight(versionOptions.Version, newVersion, versionOptions.VersionHeightPosition.Value))
             {
                 // The version will be reset by this change, so remove the version height offset property.
                 versionOptions.VersionHeightOffset = null;

test/Nerdbank.GitVersioning.Tests/ReleaseManagerTests.cs

@@ -638,6 +638,44 @@ public void PrepareRelease_ResetsVersionHeightOffset()
         Assert.Equal(expectedReleaseVersionOptions, releaseVersion);
     }
 
+    [Fact]
+    public void PrepareRelease_DoesNotResetNegativeVersionHeightOffset()
+    {
+        // create and configure repository
+        this.InitializeSourceControl();
+
+        var initialVersionOptions = new VersionOptions
+        {
+            Version = SemanticVersion.Parse("1.0-beta"),
+            VersionHeightOffset = -1,
+        };
+
+        var expectedReleaseVersionOptions = new VersionOptions
+        {
+            Version = SemanticVersion.Parse("1.0"),
+            VersionHeightOffset = -1,
+        };
+
+        var expectedMainVersionOptions = new VersionOptions
+        {
+            Version = SemanticVersion.Parse("1.1-alpha"),
+            VersionHeightOffset = -1,
+        };
+
+        // create version.json
+        this.WriteVersionFile(initialVersionOptions);
+
+        var releaseManager = new ReleaseManager();
+        releaseManager.PrepareRelease(this.RepoPath);
+
+        this.SetContextToHead();
+        VersionOptions newVersion = this.Context.VersionFile.GetVersion();
+        Assert.Equal(expectedMainVersionOptions, newVersion);
+
+        VersionOptions releaseVersion = this.GetVersionOptions(committish: this.LibGit2Repository.Branches["v1.0"].Tip.Sha);
+        Assert.Equal(expectedReleaseVersionOptions, releaseVersion);
+    }
+
     [Theory]
     [InlineData("1.0-beta", "{0} Custom commit message pattern", "1.0 Custom commit message pattern")]
     [InlineData("1.0-beta", "Custom commit message pattern - {0} custom message", "Custom commit message pattern - 1.0 custom message")]