Isolate testing of 0FC channels to standalone CI

The electrsd dev-dependency does not yet ship binaries that support
submitpackage on electrum, so we do not turn on 0FC channels in local
tests, and instead only turn them on in a standalone CI workflow, which
includes a custom electrs server that adds support for submitpackage
on electrum.

Co-Authored-By: HAL 9000

Author: tankyleo

.github/workflows/0fc-integration.yml

@@ -0,0 +1,49 @@
+name: CI Checks - 0FC Integration Tests
+
+on: [push, pull_request]
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build-and-test:
+    timeout-minutes: 60
+    runs-on: self-hosted
+    steps:
+      - name: Checkout source code
+        uses: actions/checkout@v4
+      - name: Install Rust stable toolchain
+        run: |
+          curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --profile=minimal --default-toolchain stable
+      - name: Enable caching for bitcoind
+        id: cache-bitcoind
+        uses: actions/cache@v4
+        with:
+          path: bin/bitcoind-${{ runner.os }}-${{ runner.arch }}
+          key: bitcoind-29.0-${{ runner.os }}-${{ runner.arch }}
+      - name: Enable caching for electrs
+        id: cache-electrs
+        uses: actions/cache@v4
+        with:
+          path: bin/electrs-${{ runner.os }}-${{ runner.arch }}
+          key: electrs-submit-package-${{ runner.os }}-${{ runner.arch }}
+      - name: Download bitcoind
+        if: "steps.cache-bitcoind.outputs.cache-hit != 'true'"
+        run: |
+          source ./scripts/download_bitcoind.sh
+          mkdir -p bin
+          mv "$BITCOIND_EXE" bin/bitcoind-${{ runner.os }}-${{ runner.arch }}
+      - name: Download electrs
+        if: "steps.cache-electrs.outputs.cache-hit != 'true'"
+        run: |
+          source ./scripts/build_electrs.sh
+          mkdir -p bin
+          mv "$ELECTRS_EXE" bin/electrs-${{ runner.os }}-${{ runner.arch }}
+      - name: Set bitcoind/electrs environment variables
+        run: |
+          echo "BITCOIND_EXE=$( pwd )/bin/bitcoind-${{ runner.os }}-${{ runner.arch }}" >> "$GITHUB_ENV"
+          echo "ELECTRS_EXE=$( pwd )/bin/electrs-${{ runner.os }}-${{ runner.arch }}" >> "$GITHUB_ENV"
+      - name: Test with 0FC enabled
+        run: |
+          RUSTFLAGS="--cfg no_download --cfg cycle_tests --cfg tokio_unstable --cfg zero_fee_commitment_tests" cargo test

Cargo.toml

@@ -135,6 +135,7 @@ check-cfg = [
 	"cfg(eclair_test)",
 	"cfg(cycle_tests)",
 	"cfg(hrn_tests)",
+	"cfg(zero_fee_commitment_tests)",
 ]
 
 [[bench]]

tests/common/mod.rs

@@ -382,10 +382,10 @@ pub(crate) fn random_node_alias() -> Option<NodeAlias> {
 pub(crate) fn random_config() -> TestConfig {
 	let mut node_config = Config::default();
 
-	// We want 0FC channels to be negotiated half the time, 0.49 is good enough
-	let zero_fee_commitments = rand::random_bool(0.7);
-	println!("Negotiating zero-fee commitment channels: {}", zero_fee_commitments);
-	node_config.anchor_channels_config.enable_zero_fee_commitments = zero_fee_commitments;
+	#[cfg(zero_fee_commitment_tests)]
+	{
+		node_config.anchor_channels_config.enable_zero_fee_commitments = true;
+	}
 
 	node_config.network = Network::Regtest;
 	println!("Setting network: {}", node_config.network);