Refactor channelmanager tests to test publicly visible apis

* Few tests were dependent on channelmanagers internal state, refactored
  that them to publicly visible apis

lightning/src/ln/anchor_channel_configuration_tests.rs

@@ -1,10 +1,11 @@
 use crate::events::{Event, MessageSendEvent, MessageSendEventsProvider};
-use crate::ln::msgs::ChannelMessageHandler;
+use crate::ln::types::ChannelId;
+use crate::ln::functional_test_utils::*;
 use crate::ln::msgs::ErrorAction;
-use crate::ln::{functional_test_utils::*, ChannelId};
+use crate::ln::msgs::ChannelMessageHandler;
 use crate::prelude::*;
-use crate::util::config::ChannelConfigUpdate;
 use crate::util::errors::APIError;
+use crate::util::config::ChannelConfigUpdate;
 
 #[test]
 fn test_inbound_anchors_manual_acceptance() {

lightning/src/ln/channelmanager.rs

@@ -2284,15 +2284,15 @@ pub(crate) const ENABLE_GOSSIP_TICKS: u8 = 5;
 /// The maximum number of unfunded channels we can have per-peer before we start rejecting new
 /// (inbound) ones. The number of peers with unfunded channels is limited separately in
 /// [`MAX_UNFUNDED_CHANNEL_PEERS`].
-const MAX_UNFUNDED_CHANS_PER_PEER: usize = 4;
+pub(crate) const MAX_UNFUNDED_CHANS_PER_PEER: usize = 4;
 
 /// The maximum number of peers from which we will allow pending unfunded channels. Once we reach
 /// this many peers we reject new (inbound) channels from peers with which we don't have a channel.
-const MAX_UNFUNDED_CHANNEL_PEERS: usize = 50;
+pub(crate) const MAX_UNFUNDED_CHANNEL_PEERS: usize = 50;
 
 /// The maximum number of peers which we do not have a (funded) channel with. Once we reach this
 /// many peers we reject new (inbound) connections.
-const MAX_NO_CHANNEL_PEERS: usize = 250;
+pub(crate) const MAX_NO_CHANNEL_PEERS: usize = 250;
 
 /// Information needed for constructing an invoice route hint for this channel.
 #[derive(Clone, Debug, PartialEq)]