From 07c325430e9eafe35e09cd7d6261f26250d47f09 Mon Sep 17 00:00:00 2001
From: Matthias Glauch <matthias.glauch@mgsd.eu>
Date: Thu, 27 May 2021 23:08:03 +0200
Subject: [PATCH] fixed SemVer regex (major number was optional) and added test
 for the issue caused by the wrong regex

---
 .../VersionCalculation/SemanticVersionTests.cs               | 5 +++--
 .../VersionCalculation/SemanticVersioning/SemanticVersion.cs | 2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/GitVersion.Core.Tests/VersionCalculation/SemanticVersionTests.cs b/src/GitVersion.Core.Tests/VersionCalculation/SemanticVersionTests.cs
index 1637227ffd..ef8a8f79c8 100644
--- a/src/GitVersion.Core.Tests/VersionCalculation/SemanticVersionTests.cs
+++ b/src/GitVersion.Core.Tests/VersionCalculation/SemanticVersionTests.cs
@@ -57,9 +57,10 @@ public void ValidateVersionParsing(
 
         [TestCase("someText")]
         [TestCase("some-T-ext")]
-        public void ValidateInvalidVersionParsing(string versionString)
+        [TestCase("v.1.2.3", "v")]
+        public void ValidateInvalidVersionParsing(string versionString, string tagPrefixRegex = null)
         {
-            Assert.IsFalse(SemanticVersion.TryParse(versionString, null, out _), "TryParse Result");
+            Assert.IsFalse(SemanticVersion.TryParse(versionString, tagPrefixRegex, out _), "TryParse Result");
         }
 
         [Test]
diff --git a/src/GitVersion.Core/VersionCalculation/SemanticVersioning/SemanticVersion.cs b/src/GitVersion.Core/VersionCalculation/SemanticVersioning/SemanticVersion.cs
index 3975a634f8..6b96d966d9 100644
--- a/src/GitVersion.Core/VersionCalculation/SemanticVersioning/SemanticVersion.cs
+++ b/src/GitVersion.Core/VersionCalculation/SemanticVersioning/SemanticVersion.cs
@@ -8,7 +8,7 @@ public class SemanticVersion : IFormattable, IComparable<SemanticVersion>
         private static SemanticVersion Empty = new SemanticVersion();
 
         private static readonly Regex ParseSemVer = new Regex(
-            @"^(?<SemVer>(?<Major>\d+)?(\.(?<Minor>\d+))?(\.(?<Patch>\d+))?)(\.(?<FourthPart>\d+))?(-(?<Tag>[^\+]*))?(\+(?<BuildMetaData>.*))?$",
+            @"^(?<SemVer>(?<Major>\d+)(\.(?<Minor>\d+))?(\.(?<Patch>\d+))?)(\.(?<FourthPart>\d+))?(-(?<Tag>[^\+]*))?(\+(?<BuildMetaData>.*))?$",
             RegexOptions.Compiled);
 
         public int Major;