Improve exceptions when no Mainline branches are found

Author: asbjornu

src/GitVersion.Core.Tests/IntegrationTests/MainlineDevelopmentMode.cs

@@ -5,6 +5,7 @@
 using GitVersion.VersionCalculation;
 using LibGit2Sharp;
 using NUnit.Framework;
+using Shouldly;
 
 namespace GitVersion.Core.Tests.IntegrationTests;
 
@@ -537,6 +538,32 @@ public void BranchWithoutMergeBaseMainlineBranchIsFound()
         fixture.AssertFullSemver("0.1.3-issue-branch.1", currentConfig);
     }
 
+    [Test]
+    public void GivenARemoteGitRepositoryWithCommitsThenClonedLocalDevelopShouldMatchRemoteVersion()
+    {
+        using var fixture = new RemoteRepositoryFixture();
+        fixture.AssertFullSemver("0.1.4", config);
+        fixture.BranchTo("develop");
+        fixture.AssertFullSemver("0.2.0-alpha.0", config);
+        Console.WriteLine(fixture.SequenceDiagram.GetDiagram());
+        var local = fixture.CloneRepository();
+        fixture.AssertFullSemver("0.2.0-alpha.0", config, repository: local.Repository);
+        local.Repository.DumpGraph();
+    }
+
+    [Test]
+    public void GivenNoMainThrowsWarning()
+    {
+        using var fixture = new EmptyRepositoryFixture();
+        fixture.Repository.MakeACommit();
+        fixture.Repository.MakeATaggedCommit("1.0.0");
+        fixture.Repository.MakeACommit();
+        Commands.Checkout(fixture.Repository, fixture.Repository.CreateBranch("develop"));
+        fixture.Repository.Branches.Remove(fixture.Repository.Branches["main"]);
+
+        var exception = Assert.Throws<WarningException>(() => fixture.AssertFullSemver("1.1.0-alpha.1", config));
+        exception.Message.ShouldMatch("No branches can be found matching the commit .* in the configured Mainline branches: main, support");
+    }
 }
 
 internal static class CommitExtensions

src/GitVersion.Core/VersionCalculation/MainlineVersionCalculator.cs

@@ -128,7 +128,8 @@ private IBranch GetMainline(ICommit? baseVersionSource)
 
         if (!mainlineBranches.Any())
         {
-            throw new WarningException("No mainline branches found!");
+            var mainlineBranchConfigsString = string.Join(", ", mainlineBranchConfigs.Select(b => b.Value.Name));
+            throw new WarningException($"No branches can be found matching the commit {context.CurrentCommit.Sha} in the configured Mainline branches: {mainlineBranchConfigsString}");
         }
 
         var mainlineBranchNames = mainlineBranches.Values.SelectMany(branches => branches.Select(b => b.Name.Friendly));