Drop the no-std feature from lightning-rapid-gossip-sync

Now that we don't have to have everything in our entire ecosystem
use the same `std`/`no-std` feature combinations we should start by
untangling our own features a bit.

This takes another step by removing the `no-std` feature entirely
from the `lightning-rapid-gossip-sync` crate and removing all
feature implications on dependencies from the remaining `std`
feature.

Author: TheBlueMatt

ci/ci-tests.sh

@@ -75,20 +75,20 @@ grep '^max_level_' lightning/Cargo.toml | awk '{ print $1 }'| while read -r FEAT
 done
 
 echo -e "\n\nTesting no-std builds"
-for DIR in lightning-invoice lightning-background-processor; do
+for DIR in lightning-invoice lightning-background-processor  lightning-rapid-gossip-sync; do
 	cargo test -p $DIR --verbose --color always --no-default-features
 	# check if there is a conflict between no-std and the c_bindings cfg
 	RUSTFLAGS="$RUSTFLAGS --cfg=c_bindings" cargo test -p $DIR --verbose --color always --no-default-features
 done
 
 echo -e "\n\nTesting no-std flags in various combinations"
-for DIR in lightning lightning-rapid-gossip-sync; do
+for DIR in lightning; do
 	cargo test -p $DIR --verbose --color always --no-default-features --features no-std
 	# check if there is a conflict between no-std and the default std feature
 	cargo test -p $DIR --verbose --color always --features no-std
 done
 
-for DIR in lightning lightning-rapid-gossip-sync; do
+for DIR in lightning; do
 	# check if there is a conflict between no-std and the c_bindings cfg
 	RUSTFLAGS="$RUSTFLAGS --cfg=c_bindings" cargo test -p $DIR --verbose --color always --no-default-features --features=no-std
 done

lightning-rapid-gossip-sync/Cargo.toml

@@ -11,8 +11,7 @@ Utility to process gossip routing data from Rapid Gossip Sync Server.
 
 [features]
 default = ["std"]
-no-std = ["lightning/no-std"]
-std = ["lightning/std"]
+std = []
 
 [dependencies]
 lightning = { version = "0.0.123-beta", default-features = false }

lightning-rapid-gossip-sync/src/lib.rs

@@ -143,7 +143,7 @@ where
 	///
 	/// `sync_path`: Path to the file where the gossip update data is located
 	///
-	#[cfg(all(feature = "std", not(feature = "no-std")))]
+	#[cfg(feature = "std")]
 	pub fn sync_network_graph_with_file_path(
 		&self, sync_path: &str,
 	) -> Result<u32, GraphSyncError> {
@@ -191,7 +191,7 @@ where
 	}
 }
 
-#[cfg(all(feature = "std", not(feature = "no-std")))]
+#[cfg(feature = "std")]
 #[cfg(test)]
 mod tests {
 	use std::fs;

no-std-check/Cargo.toml

@@ -4,7 +4,7 @@ version = "0.1.0"
 edition = "2021"
 
 [features]
-default = ["lightning/no-std", "lightning-rapid-gossip-sync/no-std"]
+default = ["lightning/no-std"]
 
 [dependencies]
 lightning = { path = "../lightning", default-features = false }