Remove futures feature

Now that we use core::future, the feature flag is no longer needed.

Author: joostjager

.github/workflows/build.yml

@@ -122,7 +122,7 @@ jobs:
         run: |
           cargo install cargo-llvm-cov
           export RUSTFLAGS="-Coverflow-checks=off"
-          cargo llvm-cov --features rest-client,rpc-client,tokio,futures,serde --codecov --hide-instantiations --output-path=target/codecov.json
+          cargo llvm-cov --features rest-client,rpc-client,tokio,serde --codecov --hide-instantiations --output-path=target/codecov.json
           # Could you use this to fake the coverage report for your PR? Sure.
           # Will anyone be impressed by your amazing coverage? No
           # Maybe if codecov wasn't broken we wouldn't need to do this...
@@ -232,13 +232,13 @@ jobs:
       - name: Run cargo check for release build.
         run: |
           cargo check --release
-          cargo check --no-default-features --features=futures,std --release
+          cargo check --no-default-features --features=std --release
           cargo doc --release
       - name: Run cargo check for Taproot build.
         run: |
           cargo check --release
           cargo check --no-default-features --release
-          cargo check --no-default-features --features=futures,std --release
+          cargo check --no-default-features --features=std --release
           cargo doc --release
           cargo doc --no-default-features --release
         env:

ci/ci-tests.sh

@@ -68,10 +68,6 @@ cargo check -p lightning-block-sync --verbose --color always --features rpc-clie
 cargo test -p lightning-block-sync --verbose --color always --features rpc-client,rest-client,tokio
 cargo check -p lightning-block-sync --verbose --color always --features rpc-client,rest-client,tokio
 
-echo -e "\n\nTest futures builds"
-cargo test -p lightning-background-processor --verbose --color always --features futures
-cargo test -p lightning-background-processor --verbose --color always --features futures --no-default-features
-
 echo -e "\n\nTest Custom Message Macros"
 cargo test -p lightning-custom-message --verbose --color always
 [ "$CI_MINIMIZE_DISK_USAGE" != "" ] && cargo clean
@@ -85,6 +81,7 @@ for DIR in lightning-invoice lightning-rapid-gossip-sync lightning-liquidity; do
 done
 
 cargo test -p lightning --verbose --color always --no-default-features
+cargo test -p lightning-background-processor --verbose --color always --no-default-features
 
 echo -e "\n\nTesting c_bindings builds"
 # Note that because `$RUSTFLAGS` is not passed through to doctest builds we cannot selectively
@@ -98,7 +95,7 @@ done
 
 # Note that because `$RUSTFLAGS` is not passed through to doctest builds we cannot selectively
 # disable doctests in `c_bindings` so we skip doctests entirely here.
-RUSTFLAGS="$RUSTFLAGS --cfg=c_bindings" cargo test -p lightning-background-processor --verbose --color always --features futures --no-default-features --lib --bins --tests
+RUSTFLAGS="$RUSTFLAGS --cfg=c_bindings" cargo test -p lightning-background-processor --verbose --color always --no-default-features --lib --bins --tests
 RUSTFLAGS="$RUSTFLAGS --cfg=c_bindings" cargo test -p lightning --verbose --color always --no-default-features --lib --bins --tests
 
 echo -e "\n\nTesting other crate-specific builds"

lightning-background-processor/Cargo.toml

@@ -14,7 +14,6 @@ all-features = true
 rustdoc-args = ["--cfg", "docsrs"]
 
 [features]
-futures = [ ]
 std = ["lightning/std", "lightning-liquidity/std", "bitcoin-io/std", "bitcoin_hashes/std"]
 
 default = ["std"]

lightning-background-processor/src/lib.rs

@@ -4,7 +4,6 @@
 #![deny(rustdoc::broken_intra_doc_links)]
 #![deny(rustdoc::private_intra_doc_links)]
 #![deny(missing_docs)]
-#![cfg_attr(not(feature = "futures"), deny(unsafe_code))]
 #![cfg_attr(docsrs, feature(doc_auto_cfg))]
 #![cfg_attr(all(not(feature = "std"), not(test)), no_std)]
 
@@ -25,7 +24,6 @@ use lightning::chain::chainmonitor::{ChainMonitor, Persist};
 use lightning::events::EventHandler;
 #[cfg(feature = "std")]
 use lightning::events::EventsProvider;
-#[cfg(feature = "futures")]
 use lightning::events::ReplayEvent;
 use lightning::events::{Event, PathFailure};
 
@@ -36,14 +34,12 @@ use lightning::onion_message::messenger::AOnionMessenger;
 use lightning::routing::gossip::{NetworkGraph, P2PGossipSync};
 use lightning::routing::scoring::{ScoreUpdate, WriteableScore};
 use lightning::routing::utxo::UtxoLookup;
-#[cfg(feature = "futures")]
 use lightning::sign::ChangeDestinationSource;
 #[cfg(feature = "std")]
 use lightning::sign::ChangeDestinationSourceSync;
 use lightning::sign::OutputSpender;
 use lightning::util::logger::Logger;
 use lightning::util::persist::{KVStore, Persister};
-#[cfg(feature = "futures")]
 use lightning::util::sweep::OutputSweeper;
 #[cfg(feature = "std")]
 use lightning::util::sweep::OutputSweeperSync;
@@ -146,7 +142,6 @@ const SWEEPER_TIMER: u64 = 30;
 #[cfg(test)]
 const SWEEPER_TIMER: u64 = 1;
 
-#[cfg(feature = "futures")]
 /// core::cmp::min is not currently const, so we define a trivial (and equivalent) replacement
 const fn min_u64(a: u64, b: u64) -> u64 {
 	if a < b {
@@ -155,7 +150,6 @@ const fn min_u64(a: u64, b: u64) -> u64 {
 		b
 	}
 }
-#[cfg(feature = "futures")]
 const FASTEST_TIMER: u64 = min_u64(
 	min_u64(FRESHNESS_TIMER, PING_TIMER),
 	min_u64(SCORER_PERSIST_TIMER, min_u64(FIRST_NETWORK_PRUNE_TIMER, REBROADCAST_TIMER)),
@@ -508,7 +502,6 @@ macro_rules! define_run_body {
 	} }
 }
 
-#[cfg(feature = "futures")]
 pub(crate) mod futures_util {
 	use core::future::Future;
 	use core::marker::Unpin;
@@ -622,9 +615,7 @@ pub(crate) mod futures_util {
 		unsafe { Waker::from_raw(RawWaker::new(core::ptr::null(), &DUMMY_WAKER_VTABLE)) }
 	}
 }
-#[cfg(feature = "futures")]
 use core::task;
-#[cfg(feature = "futures")]
 use futures_util::{dummy_waker, OptionalSelector, Selector, SelectorOutput};
 
 /// Processes background events in a future.
@@ -634,8 +625,10 @@ use futures_util::{dummy_waker, OptionalSelector, Selector, SelectorOutput};
 /// future which outputs `true`, the loop will exit and this function's future will complete.
 /// The `sleeper` future is free to return early after it has triggered the exit condition.
 ///
-/// See [`BackgroundProcessor::start`] for information on which actions this handles.
-///
+#[cfg_attr(
+	feature = "std",
+	doc = " See [`BackgroundProcessor::start`] for information on which actions this handles.\n"
+)]
 /// The `mobile_interruptable_platform` flag should be set if we're currently running on a
 /// mobile device, where we may need to check for interruption of the application regularly. If you
 /// are unsure, you should set the flag, as the performance impact of it is minimal unless there
@@ -775,7 +768,6 @@ use futures_util::{dummy_waker, OptionalSelector, Selector, SelectorOutput};
 #[cfg_attr(feature = "std", doc = "	handle.await.unwrap()")]
 ///	# }
 ///```
-#[cfg(feature = "futures")]
 pub async fn process_events_async<
 	'a,
 	UL: 'static + Deref,
@@ -2096,7 +2088,6 @@ mod tests {
 	}
 
 	#[tokio::test]
-	#[cfg(feature = "futures")]
 	async fn test_channel_manager_persist_error_async() {
 		// Test that if we encounter an error during manager persistence, the thread panics.
 		let (_, nodes) = create_nodes(2, "test_persist_error_sync");
@@ -2605,7 +2596,6 @@ mod tests {
 	}
 
 	#[tokio::test]
-	#[cfg(feature = "futures")]
 	async fn test_not_pruning_network_graph_until_graph_sync_completion_async() {
 		let (sender, receiver) = std::sync::mpsc::sync_channel(1);
 
@@ -2808,7 +2798,6 @@ mod tests {
 	}
 
 	#[tokio::test]
-	#[cfg(feature = "futures")]
 	async fn test_payment_path_scoring_async() {
 		let (sender, mut receiver) = tokio::sync::mpsc::channel(1);
 		let event_handler = move |event: Event| {

msrv-no-dev-deps-check/Cargo.toml

@@ -9,6 +9,6 @@ lightning-block-sync = { path = "../lightning-block-sync", features = [ "rest-cl
 lightning-invoice = { path = "../lightning-invoice" }
 lightning-net-tokio = { path = "../lightning-net-tokio" }
 lightning-persister = { path = "../lightning-persister" }
-lightning-background-processor = { path = "../lightning-background-processor", features = ["futures"] }
+lightning-background-processor = { path = "../lightning-background-processor" }
 lightning-rapid-gossip-sync = { path = "../lightning-rapid-gossip-sync" }
 lightning-custom-message = { path = "../lightning-custom-message" }

no-std-check/Cargo.toml

@@ -10,4 +10,4 @@ default = []
 lightning = { path = "../lightning", default-features = false }
 lightning-invoice = { path = "../lightning-invoice", default-features = false }
 lightning-rapid-gossip-sync = { path = "../lightning-rapid-gossip-sync", default-features = false }
-lightning-background-processor = { path = "../lightning-background-processor", features = ["futures"], default-features = false }
+lightning-background-processor = { path = "../lightning-background-processor", default-features = false }