From 7bdbbca3b064be9eadfb716392e099f19878b927 Mon Sep 17 00:00:00 2001
From: Matt Corallo <git@bluematt.me>
Date: Fri, 6 Jan 2023 19:53:47 +0000
Subject: [PATCH] Switch to hashbrown in fuzzing

hashbrown by default uses ahash, which may be a bit faster, but
more importantly, if we upgrade to hashbrown 0.13/ahash 0.8 we can
make it use a constant randomization factor, making fuzzers happier.
---
 fuzz/Cargo.toml                 | 6 ++++--
 fuzz/src/chanmon_consistency.rs | 2 +-
 fuzz/src/full_stack.rs          | 2 +-
 fuzz/src/router.rs              | 2 +-
 4 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/fuzz/Cargo.toml b/fuzz/Cargo.toml
index bc1ed6f0c..a6d91781b 100644
--- a/fuzz/Cargo.toml
+++ b/fuzz/Cargo.toml
@@ -18,11 +18,13 @@ libfuzzer_fuzz = ["libfuzzer-sys"]
 stdin_fuzz = []
 
 [dependencies]
-afl = { version = "0.12", optional = true }
-lightning = { path = "../lightning", features = ["regex"] }
+lightning = { path = "../lightning", features = ["regex", "hashbrown"] }
 lightning-rapid-gossip-sync = { path = "../lightning-rapid-gossip-sync" }
 bitcoin = { version = "0.29.0", features = ["secp-lowmemory"] }
 hex = "0.3"
+hashbrown = "0.8"
+
+afl = { version = "0.12", optional = true }
 honggfuzz = { version = "0.5", optional = true, default-features = false }
 libfuzzer-sys = { version = "0.4", optional = true }
 
diff --git a/fuzz/src/chanmon_consistency.rs b/fuzz/src/chanmon_consistency.rs
index fda004682..c9147cd83 100644
--- a/fuzz/src/chanmon_consistency.rs
+++ b/fuzz/src/chanmon_consistency.rs
@@ -61,7 +61,7 @@ use bitcoin::secp256k1::Secp256k1;
 
 use std::mem;
 use std::cmp::{self, Ordering};
-use std::collections::{HashSet, hash_map, HashMap};
+use hashbrown::{HashSet, hash_map, HashMap};
 use std::sync::{Arc,Mutex};
 use std::sync::atomic;
 use std::io::Cursor;
diff --git a/fuzz/src/full_stack.rs b/fuzz/src/full_stack.rs
index ae9e6295c..8a0b6de65 100644
--- a/fuzz/src/full_stack.rs
+++ b/fuzz/src/full_stack.rs
@@ -58,7 +58,7 @@ use bitcoin::secp256k1::ecdsa::RecoverableSignature;
 use bitcoin::secp256k1::Secp256k1;
 
 use std::cell::RefCell;
-use std::collections::{HashMap, hash_map};
+use hashbrown::{HashMap, hash_map};
 use std::convert::TryInto;
 use std::cmp;
 use std::sync::{Arc, Mutex};
diff --git a/fuzz/src/router.rs b/fuzz/src/router.rs
index cb397bdec..3e51d0c6a 100644
--- a/fuzz/src/router.rs
+++ b/fuzz/src/router.rs
@@ -29,7 +29,7 @@ use bitcoin::blockdata::constants::genesis_block;
 use crate::utils::test_logger;
 
 use std::convert::TryInto;
-use std::collections::HashSet;
+use hashbrown::HashSet;
 use std::sync::Arc;
 use std::sync::atomic::{AtomicUsize, Ordering};
 
-- 
2.39.5