From 448dd8c1d0fbbd91960069404eb2e1507102f949 Mon Sep 17 00:00:00 2001
From: Marcin Krystianc <marcin.krystianc@gmail.com>
Date: Tue, 20 Sep 2022 12:48:31 +0200
Subject: [PATCH] DeltaStreamReader should interpret 0 size as 0x10000

https://git-scm.com/docs/pack-format/2.31.0#_instruction_to_copy_from_base_object:
"In its most compact form, this instruction only takes up one byte (0x80) with both offset and size omitted, which will have default values zero. There is another exception: size zero is automatically converted to 0x10000."
---
 src/NerdBank.GitVersioning/ManagedGit/DeltaStreamReader.cs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/NerdBank.GitVersioning/ManagedGit/DeltaStreamReader.cs b/src/NerdBank.GitVersioning/ManagedGit/DeltaStreamReader.cs
index 08ee301e..a23020a9 100644
--- a/src/NerdBank.GitVersioning/ManagedGit/DeltaStreamReader.cs
+++ b/src/NerdBank.GitVersioning/ManagedGit/DeltaStreamReader.cs
@@ -84,6 +84,12 @@ public static class DeltaStreamReader
                 {
                     value.Size |= ((byte)stream.ReadByte() << 16);
                 }
+
+                // Size zero is automatically converted to 0x10000.
+                if (value.Size == 0)
+                {
+                    value.Size = 0x10000;
+                }
             }
 
             return value;