Add test case

Author: Turnerj

src/GitVersion.Core.Tests/Configuration/ConfigExtensionsTests.cs

@@ -0,0 +1,30 @@
+using GitVersion.Configuration;
+using GitVersion.Core.Tests.Helpers;
+using GitVersion.Model.Configuration;
+using NUnit.Framework;
+using Shouldly;
+
+namespace GitVersion.Core.Tests.Configuration;
+
+[TestFixture]
+public class ConfigExtensionsTests : TestBase
+{
+    [Test]
+    public void GetReleaseBranchConfigReturnsAllReleaseBranches()
+    {
+        var config = new Config()
+        {
+            Branches = new Dictionary<string, BranchConfig>
+            {
+                { "foo", new BranchConfig { Name = "foo" } },
+                { "bar", new BranchConfig { Name = "bar", IsReleaseBranch = true } },
+                { "baz", new BranchConfig { Name = "baz", IsReleaseBranch = true } }
+            }
+        };
+
+        var result = config.GetReleaseBranchConfig();
+
+        result.Count.ShouldBe(2);
+        result.ShouldNotContain(b => b.Key == "foo");
+    }
+}