Add MemberNotNullWhen to SemanticVersion.HasMetadata (#5465)

NuGet · Oct 23, 2023 · b02fdbb · b02fdbb
1 parent 041c6da
commit b02fdbb
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Showing 2 changed files with 17 additions and 1 deletion.
diff --git a/src/NuGet.Core/NuGet.Versioning/SemanticVersion.cs b/src/NuGet.Core/NuGet.Versioning/SemanticVersion.cs
@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 
 namespace NuGet.Versioning
@@ -231,6 +232,7 @@ public virtual bool IsPrerelease
         /// <summary>
         /// True if metadata exists for the version.
         /// </summary>
+        [MemberNotNullWhen(true, nameof(Metadata))]
         public virtual bool HasMetadata
         {
             get { return !string.IsNullOrEmpty(Metadata); }

diff --git a/test/NuGet.Core.Tests/NuGet.Versioning.Test/SemanticVersionTests.cs b/test/NuGet.Core.Tests/NuGet.Versioning.Test/SemanticVersionTests.cs
@@ -90,7 +90,7 @@ public void SemanticVersionStrictEqualityPreRelease(string versionString)
         [InlineData("1.2.3-A.00.B")]
         public void TryParseStrictReturnsFalseIfVersionIsNotStrictSemVer(string version)
         {
-            // Act 
+            // Act
             SemanticVersion? semanticVersion;
             var result = SemanticVersion.TryParse(version, out semanticVersion);
 
@@ -109,6 +109,20 @@ public void ToString_ClassExtendingSemanticVersion_ReturnsDefaultFormat()
             Assert.Equal("1.2.3", result);
         }
 
+        [Fact]
+        public void Metadata_NoNullableWarning_After_HasMetadata_checked()
+        {
+            // Arrange
+            SemanticVersion target = new(1, 2, 3);
+
+            // Act
+            // should not result in a compiler warning CS8602: Dereference of a possibly null reference.
+            string result = target.HasMetadata ? target.Metadata.Substring(1) : "no-metadata";
+
+            // Assert
+            Assert.Equal("no-metadata", result);
+        }
+
         private class ExtendedSemanticVersion : SemanticVersion
         {
             public ExtendedSemanticVersion(int major, int minor, int patch)