expect004.diff

--- test004.left.txt
+++ test004.right.txt
@@ -1,3 +1,10 @@
+int Chunk_bounds_check(Chunk *chunk, size_t start, size_t n)
+{
+    if (chunk == NULL) return 0;
+
+    return start <= chunk->length && n <= chunk->length - start;
+}
+
 void Chunk_copy(Chunk *src, size_t src_start, Chunk *dst, size_t dst_start, size_t n)
 {
     if (!Chunk_bounds_check(src, src_start, n)) return;
@@ -5,10 +12,3 @@
 
     memcpy(dst->data + dst_start, src->data + src_start, n);
 }
-
-int Chunk_bounds_check(Chunk *chunk, size_t start, size_t n)
-{
-    if (chunk == NULL) return 0;
-
-    return start <= chunk->length && n <= chunk->length - start;
-}