From 4a31b93cb35dfdc4d9099ad1ec01f1f6da0455db Mon Sep 17 00:00:00 2001
From: Alexander Grund <alexander.grund@tu-dresden.de>
Date: Tue, 26 Nov 2024 09:48:06 +0100
Subject: [PATCH] GHA: Cache boost checkout

Instead of cloning the Boost main repository and later potentially many
submodules (by `depinst.py`) we can cache the last checkout.
On any changes the checkout-and-pull should update it to the appropriate
version.
---
 .github/workflows/ci.yml | 17 +++++++++++++++++
 ci/common_install.sh     |  2 ++
 2 files changed, 19 insertions(+)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 49e48fe3..5d3ce3c6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -245,6 +245,19 @@ jobs:
           BDDE_ARCH: ${{matrix.arch}}
         run: ci/github/setup_bdde.sh
 
+      - name: Cache Boost checkout
+        uses: actions/cache@v3
+        if: env.GHA_USE_NODE_20 == 'false'
+        with:
+          path: boost-root
+          key: boost-checkout-cache-${{matrix.os}}-${{matrix.container}}
+      - name: Cache Boost checkout
+        uses: actions/cache@v4
+        if: env.GHA_USE_NODE_20 == 'true'
+        with:
+          path: boost-root
+          key: boost-checkout-cache-${{matrix.os}}-${{matrix.container}}
+
       - name: Setup Boost
         env:
           B2_ADDRESS_MODEL: ${{matrix.address-model}}
@@ -292,6 +305,10 @@ jobs:
           COVERITY_SCAN_NOTIFICATION_EMAIL: ${{ secrets.COVERITY_SCAN_NOTIFICATION_EMAIL }}
           COVERITY_SCAN_TOKEN: ${{ secrets.COVERITY_SCAN_TOKEN }}
 
+      - name: Prepare for cache
+        if: ${{ env.BOOST_ROOT != '' }}
+        run: rm -rf boost-root; mv "${BOOST_ROOT}" boost-root
+        working-directory: ${{github.workspace}}
   windows:
     defaults:
       run:
diff --git a/ci/common_install.sh b/ci/common_install.sh
index 01eada0d..b8cd5de3 100644
--- a/ci/common_install.sh
+++ b/ci/common_install.sh
@@ -43,6 +43,8 @@ else
     export BOOST_BRANCH="develop"
 fi
 
+# CI cache might have restored the boost-root folder in the current directory
+[ ! -d boost-root ] || mv boost-root ..
 cd ..
 
 if [ ! -d boost-root ]; then