From 25c7d1f4a9c83183dd7c8d7b167c16eccdc55763 Mon Sep 17 00:00:00 2001
From: overlookmotel <theoverlookmotel@gmail.com>
Date: Wed, 14 Feb 2024 02:10:31 +0000
Subject: [PATCH] Fix `Bump::shrink` illegal copies

Fixes #230.
---
 src/lib.rs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/lib.rs b/src/lib.rs
index 600f6ad..1b00f50 100755
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1724,7 +1724,10 @@ impl Bump {
                 // Only reclaim the excess space (which requires a copy) if it
                 // is worth it: we are actually going to recover "enough" space
                 // and we can do a non-overlapping copy.
-                && delta >= old_size / 2
+                // `(old_size + 1) / 2` so division rounds up rather than down,
+                // so this test fails for e.g. `old_size` = 1, `new_size` = 1
+                // or `old_size` = 5, `new_size` = 3 (which would overlap).
+                && delta >= (old_size + 1) / 2
         {
             let footer = self.current_chunk_footer.get();
             let footer = footer.as_ref();