Ensure we build if a downstream crate sets --cfg=fuzzing

Downstream crates building fur fuzzing will usually set
`--cfg=fuzzing` as a side-effect of the Rust fuzzing tooling. Thus,
we should ensure we build without failure in such cases.

We do this here by simply relying on the `_test_utils` feature,
rather than conditionally-compiling in modules based on the
`fuzzing` flag.

Author: TheBlueMatt

lightning/src/chain/chainmonitor.rs

@@ -502,7 +502,7 @@ where C::Target: chain::Filter,
 		self.event_notifier.notify();
 	}
 
-	#[cfg(any(test, fuzzing, feature = "_test_utils"))]
+	#[cfg(any(test, feature = "_test_utils"))]
 	pub fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
 		use crate::events::EventsProvider;
 		let events = core::cell::RefCell::new(Vec::new());

lightning/src/lib.rs

@@ -37,8 +37,8 @@
 //!     * `max_level_debug`
 //!     * `max_level_trace`
 
-#![cfg_attr(not(any(test, fuzzing, feature = "_test_utils")), deny(missing_docs))]
-#![cfg_attr(not(any(test, fuzzing, feature = "_test_utils")), forbid(unsafe_code))]
+#![cfg_attr(not(any(test, feature = "_test_utils")), deny(missing_docs))]
+#![cfg_attr(not(any(test, feature = "_test_utils")), forbid(unsafe_code))]
 
 // Prefix these with `rustdoc::` when we update our MSRV to be >= 1.52 to remove warnings.
 #![deny(broken_intra_doc_links)]
@@ -67,7 +67,7 @@ extern crate bitcoin;
 extern crate core;
 
 #[cfg(any(test, feature = "_test_utils"))] extern crate hex;
-#[cfg(any(test, fuzzing, feature = "_test_utils"))] extern crate regex;
+#[cfg(any(test, feature = "_test_utils"))] extern crate regex;
 
 #[cfg(not(feature = "std"))] extern crate core2;
 

lightning/src/ln/channelmanager.rs

@@ -6171,7 +6171,7 @@ where
 		inflight_htlcs
 	}
 
-	#[cfg(any(test, fuzzing, feature = "_test_utils"))]
+	#[cfg(any(test, feature = "_test_utils"))]
 	pub fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
 		let events = core::cell::RefCell::new(Vec::new());
 		let event_handler = |event: events::Event| events.borrow_mut().push(event);

lightning/src/util/mod.rs

@@ -50,11 +50,11 @@ pub(crate) mod crypto;
 pub mod logger;
 pub mod config;
 
-#[cfg(any(test, fuzzing, feature = "_test_utils"))]
+#[cfg(any(test, feature = "_test_utils"))]
 pub mod test_utils;
 
 /// impls of traits that add exra enforcement on the way they're called. Useful for detecting state
 /// machine errors and used in fuzz targets and tests.
-#[cfg(any(test, fuzzing, feature = "_test_utils"))]
+#[cfg(any(test, feature = "_test_utils"))]
 pub mod enforcing_trait_impls;
 

lightning/src/util/test_utils.rs

@@ -45,6 +45,7 @@ use bitcoin::secp256k1::{SecretKey, PublicKey, Secp256k1, ecdsa::Signature, Scal
 use bitcoin::secp256k1::ecdh::SharedSecret;
 use bitcoin::secp256k1::ecdsa::RecoverableSignature;
 
+#[cfg(any(test, feature = "_test_utils"))]
 use regex;
 
 use crate::io;
@@ -738,6 +739,7 @@ impl TestLogger {
 	/// 1. belong to the specified module and
 	/// 2. match the given regex pattern.
 	/// Assert that the number of occurrences equals the given `count`
+	#[cfg(any(test, feature = "_test_utils"))]
 	pub fn assert_log_regex(&self, module: &str, pattern: regex::Regex, count: usize) {
 		let log_entries = self.lines.lock().unwrap();
 		let l: usize = log_entries.iter().filter(|&(&(ref m, ref l), _c)| {