From 655d580ab7834b08482d27529e7dcbeaa9e0cb64 Mon Sep 17 00:00:00 2001
From: Elias Rohrer <dev@tnull.de>
Date: Fri, 24 Jan 2025 13:14:06 +0100
Subject: [PATCH] Add SemVer compatibility checks to CI

We recently introduced release branches that need to remain backwards
compatible. However, even small changes to item visibility during
backporting fixes might introduce SemVer violations (see
https://doc.rust-lang.org/cargo/reference/semver.html#change-categories
for a list of changs that would be considered major/minor).

To make sure we don't accidentally introduce such changes in the
backports, we here add a new `semver-checks` CI job that utilizes
`cargo-semver-checks`
(https://github.com/obi1kenobi/cargo-semver-checks), and have it run on
any push or pull requests towards anything else but `main`/`master`
(i.e., all feature branches to come).
---
 .github/workflows/semver.yml | 57 ++++++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 .github/workflows/semver.yml

diff --git a/.github/workflows/semver.yml b/.github/workflows/semver.yml
new file mode 100644
index 00000000000..73723fe34c3
--- /dev/null
+++ b/.github/workflows/semver.yml
@@ -0,0 +1,57 @@
+name: SemVer checks
+on:
+  push:
+    branches-ignore:
+      - master
+  pull_request:
+    branches-ignore:
+      - master
+
+jobs:
+  semver-checks:
+    runs-on: ubuntu-latest
+    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
+          rustup override set stable
+      - name: Check SemVer with default features
+        uses: obi1kenobi/cargo-semver-checks-action@v2
+        with:
+            feature-group: default-features
+      - name: Check SemVer *without* default features
+        uses: obi1kenobi/cargo-semver-checks-action@v2
+        with:
+            feature-group: only-explicit-features
+      - name: Check lightning-background-processor SemVer
+        uses: obi1kenobi/cargo-semver-checks-action@v2
+        with:
+            package: lightning-background-processor
+            feature-group: only-explicit-features
+            features: futures
+      - name: Check lightning-block-sync SemVer
+        uses: obi1kenobi/cargo-semver-checks-action@v2
+        with:
+            package: lightning-block-sync
+            feature-group: only-explicit-features
+            features: rpc-client,rest-client
+      - name: Check lightning-transaction-sync electrum SemVer
+        uses: obi1kenobi/cargo-semver-checks-action@v2
+        with:
+            manifest-path: lightning-transaction-sync/Cargo.toml
+            feature-group: only-explicit-features
+            features: electrum
+      - name: Check lightning-transaction-sync esplora-blocking SemVer
+        uses: obi1kenobi/cargo-semver-checks-action@v2
+        with:
+            manifest-path: lightning-transaction-sync/Cargo.toml
+            feature-group: only-explicit-features
+            features: esplora-blocking
+      - name: Check lightning-transaction-sync esplora-async SemVer
+        uses: obi1kenobi/cargo-semver-checks-action@v2
+        with:
+            manifest-path: lightning-transaction-sync/Cargo.toml
+            feature-group: only-explicit-features
+            features: esplora-async