Use raw commit message when rewriting history

LibGit2Sharp/Commit.cs

@@ -21,6 +21,7 @@ public class Commit : GitObject
         private readonly ILazy<Signature> lazyAuthor;
         private readonly ILazy<Signature> lazyCommitter;
         private readonly ILazy<string> lazyMessage;
+        private readonly ILazy<string> lazyMessageRaw;
         private readonly ILazy<string> lazyMessageShort;
         private readonly ILazy<string> lazyEncoding;
 
@@ -43,6 +44,7 @@ internal Commit(Repository repo, ObjectId id)
             lazyCommitter = group1.AddLazy(Proxy.git_commit_committer);
             group2 = new GitObjectLazyGroup(this.repo, id);
             lazyMessage = group2.AddLazy(Proxy.git_commit_message);
+            lazyMessageRaw = group2.AddLazy(Proxy.git_commit_message_raw);
             lazyMessageShort = group2.AddLazy(Proxy.git_commit_summary);
             lazyEncoding = group2.AddLazy(RetrieveEncodingOf);
 
@@ -66,6 +68,11 @@ public virtual TreeEntry this[string relativePath]
         /// </summary>
         public virtual string Message { get { return lazyMessage.Value; } }
 
+        /// <summary>
+        /// Gets the raw, unmodified commit message.
+        /// </summary>
+        public virtual string MessageRaw { get { return lazyMessageRaw.Value; } }
+
         /// <summary>
         /// Gets the short commit message which is usually the first line of the commit.
         /// </summary>

LibGit2Sharp/CommitRewriteInfo.cs

@@ -31,7 +31,7 @@ public static CommitRewriteInfo From(Commit commit)
             {
                 Author = commit.Author,
                 Committer = commit.Committer,
-                Message = commit.Message
+                Message = commit.MessageRaw
             };
         }
 

LibGit2Sharp/Core/NativeMethods.cs

@@ -422,6 +422,10 @@ internal static extern unsafe int git_commit_create_with_signature(
         [return: MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(LaxUtf8NoCleanupMarshaler))]
         internal static extern unsafe string git_commit_message(git_object* commit);
 
+        [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
+        [return: MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(LaxUtf8NoCleanupMarshaler))]
+        internal static extern unsafe string git_commit_message_raw(git_object* commit);
+
         [DllImport(libgit2, CallingConvention = CallingConvention.Cdecl)]
         [return: MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(LaxUtf8NoCleanupMarshaler))]
         internal static extern unsafe string git_commit_summary(git_object* commit);

LibGit2Sharp/Core/Proxy.cs

@@ -388,6 +388,11 @@ public static unsafe string git_commit_message(ObjectHandle obj)
             return NativeMethods.git_commit_message(obj);
         }
 
+        public static unsafe string git_commit_message_raw(ObjectHandle obj)
+        {
+            return NativeMethods.git_commit_message_raw(obj);
+        }
+
         public static unsafe string git_commit_summary(ObjectHandle obj)
         {
             return NativeMethods.git_commit_summary(obj);