From 990031444dde4da223adcadfd2f2824f5baa0812 Mon Sep 17 00:00:00 2001
From: Andrew Kelley <andrew@ziglang.org>
Date: Thu, 1 May 2025 18:23:02 -0700
Subject: [PATCH] std.io.Reader: add assertion to verify counts

---
 lib/std/io/Reader.zig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/std/io/Reader.zig b/lib/std/io/Reader.zig
index 096fe72afe0afdc1ee30a3ab66257c48c671cafa..952377f34bd0f7d6255d017ec93cfcc6dd2a1c65 100644
--- a/lib/std/io/Reader.zig
+++ b/lib/std/io/Reader.zig
@@ -131,8 +131,10 @@ pub const Limit = enum(usize) {
 };
 
 pub fn read(r: Reader, bw: *BufferedWriter, limit: Limit) RwError!usize {
+    const before = bw.count;
     const n = try r.vtable.read(r.context, bw, limit);
     assert(n <= @intFromEnum(limit));
+    assert(bw.count == before + n);
     return n;
 }
 
-- 
2.54.0