GitPackMemoryCache: Dispose of all cached streams on .Dispose()

- Implement GitPackCache.Dispose
- Dispose GitPackCache in GitPack.Dispose()
- Dispose GitRepository in ManagedGitContext.Dispose()

Author: qmfrederik

src/NerdBank.GitVersioning/Managed/ManagedGitContext.cs

@@ -119,6 +119,12 @@ public override string GetShortUniqueCommitId(int minLength)
             return this.Repository.ShortenObjectId(this.Commit.Value.Sha, minLength);
         }
 
+        /// <inheritdoc/>
+        protected override void Dispose(bool disposing)
+        {
+            this.Repository.Dispose();
+        }
+
         /// <summary>
         /// Encodes a commit from history in a <see cref="Version"/>
         /// so that the original commit can be found later.

src/NerdBank.GitVersioning/ManagedGit/GitPack.cs

@@ -259,6 +259,7 @@ public void Dispose()
 
             this.accessor.Dispose();
             this.packFile.Dispose();
+            this.cache.Dispose();
         }
 
         private long? GetOffset(GitObjectId objectId)

src/NerdBank.GitVersioning/ManagedGit/GitPackCache.cs

@@ -1,5 +1,6 @@
 #nullable enable
 
+using System;
 using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Text;
@@ -12,7 +13,7 @@ namespace Nerdbank.GitVersioning.ManagedGit
     /// data from a <see cref="GitPack"/> can be potentially expensive: the data is
     /// compressed and can be deltified.
     /// </summary>
-    public abstract class GitPackCache
+    public abstract class GitPackCache : IDisposable
     {
         /// <summary>
         /// Attempts to retrieve a Git object from cache.
@@ -51,5 +52,10 @@ public abstract class GitPackCache
         /// A <see cref="Stream"/> which represents the cached entry.
         /// </returns>
         public abstract Stream Add(long offset, Stream stream);
+
+        /// <inheritdoc/>
+        public virtual void Dispose()
+        {
+        }
     }
 }

src/NerdBank.GitVersioning/ManagedGit/GitPackMemoryCache.cs

@@ -3,6 +3,7 @@
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.IO;
+using System.Linq;
 using System.Text;
 
 namespace Nerdbank.GitVersioning.ManagedGit
@@ -55,5 +56,17 @@ public override void GetCacheStatistics(StringBuilder builder)
         {
             builder.AppendLine($"{this.cache.Count} items in cache");
         }
+
+        /// <inheritdoc/>
+        public override void Dispose()
+        {
+            while (this.cache.Count > 0)
+            {
+                var key = this.cache.Keys.First();
+                var stream = this.cache[key];
+                stream.Dispose();
+                this.cache.Remove(key);
+            }
+        }
     }
 }

src/NerdBank.GitVersioning/ManagedGit/GitPackMemoryCacheStream.cs

@@ -99,6 +99,12 @@ public override void Write(byte[] buffer, int offset, int count)
             throw new NotSupportedException();
         }
 
+        protected override void Dispose(bool disposing)
+        {
+            this.stream.Dispose();
+            this.cacheStream.Dispose();
+        }
+
         private void DisposeStreamIfRead()
         {
             if (this.cacheStream.Length == this.stream.Length)