Use alloc::collections in no_std builds

In no_std builds, replace std::collections types with alloc::collections counterparts

lightning/src/lib.rs

@@ -34,6 +34,7 @@ extern crate bitcoin;
 #[cfg(any(test, feature = "_test_utils"))] extern crate hex;
 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))] extern crate regex;
 
+#[cfg(feature = "no_std")] extern crate alloc;
 #[cfg(feature = "no_std")] extern crate core;
 #[cfg(feature = "no_std")] extern crate hashbrown;
 

lightning/src/ln/functional_tests.rs

@@ -47,11 +47,12 @@ use bitcoin::secp256k1::key::{PublicKey,SecretKey};
 
 use regex;
 
-use std::collections::BTreeSet;
 #[cfg(not(feature = "no_std"))]
-use std::collections::{HashMap, HashSet};
+use std::collections::{BTreeSet, HashMap, HashSet};
 #[cfg(feature = "no_std")]
 use hashbrown::{HashMap, HashSet};
+#[cfg(feature = "no_std")]
+use alloc::collections::BTreeSet;
 use std::default::Default;
 use std::sync::Mutex;
 #[cfg(not(feature = "no_std"))]

lightning/src/ln/peer_handler.rs

@@ -30,7 +30,10 @@ use util::events::{MessageSendEvent, MessageSendEventsProvider};
 use util::logger::Logger;
 use routing::network_graph::NetGraphMsgHandler;
 
+#[cfg(not(feature = "no_std"))]
 use std::collections::LinkedList;
+#[cfg(feature = "no_std")]
+use alloc::collections::LinkedList;
 #[cfg(not(feature = "no_std"))]
 use std::collections::{HashMap, HashSet, hash_map};
 #[cfg(feature = "no_std")]

lightning/src/routing/network_graph.rs

@@ -41,8 +41,10 @@ use std::sync::atomic::{AtomicUsize, Ordering};
 #[cfg(feature = "no_std")]
 use core::sync::atomic::{AtomicUsize, Ordering};
 use std::sync::Mutex;
-use std::collections::BTreeMap;
-use std::collections::btree_map::Entry as BtreeEntry;
+#[cfg(not(feature = "no_std"))]
+use std::collections::{BTreeMap, btree_map::Entry as BtreeEntry};
+#[cfg(feature = "no_std")]
+use alloc::collections::{BTreeMap, btree_map::Entry as BtreeEntry};
 use bitcoin::hashes::hex::ToHex;
 
 /// The maximum number of extra bytes which we do not understand in a gossip message before we will

lightning/src/routing/router.rs

@@ -25,7 +25,10 @@ use util::logger::Logger;
 use std::{cmp, ops::Deref};
 #[cfg(feature = "no_std")]
 use core::{cmp, ops::Deref};
+#[cfg(not(feature = "no_std"))]
 use std::collections::BinaryHeap;
+#[cfg(feature = "no_std")]
+use alloc::collections::BinaryHeap;
 #[cfg(not(feature = "no_std"))]
 use std::collections::HashMap;
 #[cfg(feature = "no_std")]