[CI] Update actions, add cache for faster builds.

.github/workflows/build_release.yml

@@ -1,13 +1,17 @@
 name: 🔧 Build -> Package 📦
 on: [push, pull_request]
 
+env:
+  # Only used for the cache key. Increment version to force clean build.
+  GODOT_BASE_BRANCH: master
+
 jobs:
   static-checks:
     name: 📊 Static Checks (clang-format, black format, file format)
     runs-on: ubuntu-20.04
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
 
       - name: Install dependencies
         run: |
@@ -42,11 +46,13 @@ jobs:
             gdnative_flags: 'android_arch=x86_64'
             sconsflags: ''
             os: 'ubuntu-20.04'
+            cache-name: android-x86_64
           - platform: android
             arch: 'arm64'
             gdnative_flags: 'android_arch=arm64v8'
             sconsflags: ''
             os: 'ubuntu-20.04'
+            cache-name: android-arm64
 
           # iOS
           - platform: ios
@@ -54,12 +60,13 @@ jobs:
             gdnative_flags: 'ios_arch=x86_64'
             sconsflags: 'ios_simulator=true'
             os: 'macos-latest'
+            cache-name: ios-x86_64-simulator
           - platform: ios
             arch: 'arm64'
             gdnative_flags: 'ios_arch=arm64'
             sconsflags: ''
             os: 'macos-11'
-
+            cache-name: ios-arm64
 
           # Linux
           - platform: linux
@@ -67,11 +74,13 @@ jobs:
             gdnative_flags: 'bits=32'
             sconsflags: ''
             os: 'ubuntu-20.04'
+            cache-name: linux-x86_32
           - platform: linux
             arch: 'x86_64'
             gdnative_flags: 'bits=64'
             sconsflags: ''
             os: 'ubuntu-20.04'
+            cache-name: linux-x86_64
 
           # macOS
           - platform: macos
@@ -79,11 +88,13 @@ jobs:
             gdnative_flags: 'macos_arch=x86_64 bits=64'
             sconsflags: ''
             os: 'macos-11'
+            cache-name: macos-x86_64
           - platform: macos
             gdnative_flags: 'macos_arch=arm64 bits=64'
             arch: 'arm64'
             sconsflags: ''
             os: 'macos-11'
+            cache-name: macos-arm64
 
           # Windows
           - platform: windows
@@ -92,14 +103,17 @@ jobs:
             sconsflags: 'use_mingw=yes'
             os: 'ubuntu-20.04'
             msvc_arch: amd64_x86
+            cache-name: win-x86_32
           - platform: windows
             arch: 'x86_64'
             gdnative_flags: 'bits=64'
             sconsflags: 'use_mingw=yes'
             os: 'ubuntu-20.04'
             msvc_arch: amd64
+            cache-name: win-x86_64
 
     env:
+      SCONS_CACHE: ${{ github.workspace }}/.scons-cache/
       SCONSFLAGS: ${{ matrix.sconsflags }} platform=${{ matrix.platform }} arch=${{ matrix.arch }} --jobs=2
 
     defaults:
@@ -107,10 +121,16 @@ jobs:
         shell: bash
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           submodules: recursive
 
+      - name: Setup Godot build cache
+        uses: ./godot-cpp/.github/actions/godot-cache
+        with:
+          cache-name: ${{ matrix.cache-name }}
+        continue-on-error: true
+
       - name: Install Windows build dependencies
         if: ${{ matrix.platform == 'windows' }}
         run: |
@@ -129,7 +149,7 @@ jobs:
           sudo apt-get install build-essential gcc-multilib g++-multilib
 
       - name: Set up Python 3.x
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
         with:
           python-version: '3.x'
           architecture: 'x64'
@@ -168,7 +188,7 @@ jobs:
     needs: build
     runs-on: "ubuntu-latest"
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           submodules: recursive
 

SConstruct

@@ -28,6 +28,11 @@ if env["godot_version"] == "3":
 
     env = SConscript("godot-cpp-3.x/SConstruct")
 
+    scons_cache_path = os.environ.get("SCONS_CACHE")
+    if scons_cache_path is not None:
+        CacheDir(scons_cache_path)
+        Decider("MD5")
+
     # Patch base env
     replace_flags(env["CCFLAGS"], {
         "-mios-simulator-version-min=10.0": "-mios-simulator-version-min=11.0",