From e584aa0e784681f6331e5a8f6a0beb16be4bf731 Mon Sep 17 00:00:00 2001
From: Matt Keeter <matt@oxide.computer>
Date: Mon, 30 Oct 2023 15:11:33 -0400
Subject: [PATCH] Add assertion

---
 downstairs/src/extent_inner_raw.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/downstairs/src/extent_inner_raw.rs b/downstairs/src/extent_inner_raw.rs
index eeb0d28a0..b8459d8b1 100644
--- a/downstairs/src/extent_inner_raw.rs
+++ b/downstairs/src/extent_inner_raw.rs
@@ -1317,6 +1317,10 @@ impl RawLayout {
     /// Write out the active context array and metadata section of the file
     ///
     /// This is done in a single write, so it should be atomic.
+    ///
+    /// # Panics
+    /// `active_context.len()` must match `self.block_count()`, and the function
+    /// will panic otherwise.
     fn write_active_context_and_metadata(
         &self,
         file: &File,
@@ -1325,6 +1329,8 @@ impl RawLayout {
         flush_number: u64,
         gen_number: u64,
     ) -> Result<(), CrucibleError> {
+        assert_eq!(active_context.len(), self.block_count() as usize);
+
         // Serialize bitpacked active slot values
         let mut buf = self.buf.take();
         buf.clear();