Added GitHub actions to build for CXX when supported

.github/workflows/build-emscripten-cxx.yml

@@ -0,0 +1,37 @@
+name: Build Emscripten as C++
+
+on: [push, pull_request]
+
+env:
+  # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)
+  BUILD_TYPE: Release
+
+jobs:
+ build-emsdk:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: mymindstorm/setup-emsdk@v7
+      
+      - uses: actions/checkout@v2
+      
+      - name: Create Build Environment
+        # Some projects don't allow in-source building, so create a separate build directory
+        # We'll use this as our working directory for all subsequent commands
+        run: emcmake cmake -E make_directory ${{github.workspace}}/build
+
+      - name: Configure CMake
+        # Use a bash shell so we can use the same syntax for environment variable
+        # access regardless of the host operating system
+        shell: bash
+        working-directory: ${{github.workspace}}/build
+        # Note the current convention is to use the -S and -B options here to specify source 
+        # and build directories, but this is only available with CMake 3.13 and higher.  
+        # The CMake binaries on the Github Actions machines are (as of this writing) 3.12
+        run: emcmake cmake $GITHUB_WORKSPACE -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DLUA_BUILD_AS_CXX=ON
+
+      - name: Build
+        working-directory: ${{github.workspace}}/build
+        shell: bash
+        # Execute the build.  You can specify a specific target with "--target <NAME>"
+        run: cmake --build . --config $BUILD_TYPE
+

.github/workflows/build-emscripten.yml

@@ -1,6 +1,6 @@
 name: Build Emscripten
 
-on: [push]
+on: [push, pull_request]
 
 env:
   # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)

.github/workflows/build-linux-cxx.yml

@@ -0,0 +1,46 @@
+name: Build Linux as C++
+
+on: [push, pull_request]
+
+env:
+  # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)
+  BUILD_TYPE: Release
+
+jobs:
+  build:
+    # The CMake configure and build commands are platform agnostic and should work equally
+    # well on Windows or Mac.  You can convert this to a matrix build if you need
+    # cross-platform coverage.
+    # See: https://docs.github.com/en/free-pro-team@latest/actions/learn-github-actions/managing-complex-workflows#using-a-build-matrix
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest]
+    runs-on: ${{ matrix.os }}
+    name: build-${{ matrix.os }}
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Create Build Environment
+      # Some projects don't allow in-source building, so create a separate build directory
+      # We'll use this as our working directory for all subsequent commands
+      run: cmake -E make_directory ${{github.workspace}}/build
+
+    - name: Configure CMake
+      # Use a bash shell so we can use the same syntax for environment variable
+      # access regardless of the host operating system
+      shell: bash
+      working-directory: ${{github.workspace}}/build
+      # Note the current convention is to use the -S and -B options here to specify source 
+      # and build directories, but this is only available with CMake 3.13 and higher.  
+      # The CMake binaries on the Github Actions machines are (as of this writing) 3.12
+      run: cmake $GITHUB_WORKSPACE -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DLUA_BUILD_AS_CXX=ON
+
+    - name: Build
+      working-directory: ${{github.workspace}}/build
+      shell: bash
+      # Execute the build.  You can specify a specific target with "--target <NAME>"
+      run: cmake --build . --config $BUILD_TYPE
+
+  

.github/workflows/build-linux.yml

@@ -1,6 +1,6 @@
 name: Build Linux
 
-on: [push]
+on: [push, pull_request]
 
 env:
   # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)

.github/workflows/build-osx-cxx.yml

@@ -0,0 +1,46 @@
+name: Build OSX as C++
+
+on: [push, pull_request]
+
+env:
+  # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)
+  BUILD_TYPE: Release
+
+jobs:
+  build:
+    # The CMake configure and build commands are platform agnostic and should work equally
+    # well on Windows or Mac.  You can convert this to a matrix build if you need
+    # cross-platform coverage.
+    # See: https://docs.github.com/en/free-pro-team@latest/actions/learn-github-actions/managing-complex-workflows#using-a-build-matrix
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ macos-latest ]
+    runs-on: ${{ matrix.os }}
+    name: build-${{ matrix.os }}
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Create Build Environment
+      # Some projects don't allow in-source building, so create a separate build directory
+      # We'll use this as our working directory for all subsequent commands
+      run: cmake -E make_directory ${{github.workspace}}/build
+
+    - name: Configure CMake
+      # Use a bash shell so we can use the same syntax for environment variable
+      # access regardless of the host operating system
+      shell: bash
+      working-directory: ${{github.workspace}}/build
+      # Note the current convention is to use the -S and -B options here to specify source 
+      # and build directories, but this is only available with CMake 3.13 and higher.  
+      # The CMake binaries on the Github Actions machines are (as of this writing) 3.12
+      run: cmake $GITHUB_WORKSPACE -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DLUA_BUILD_AS_CXX=ON
+
+    - name: Build
+      working-directory: ${{github.workspace}}/build
+      shell: bash
+      # Execute the build.  You can specify a specific target with "--target <NAME>"
+      run: cmake --build . --config $BUILD_TYPE
+
+  

.github/workflows/build-osx.yml

@@ -1,6 +1,6 @@
 name: Build OSX
 
-on: [push]
+on: [push, pull_request]
 
 env:
   # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)

.github/workflows/build-windows-cxx.yml

@@ -0,0 +1,46 @@
+name: Build Windows as C++
+
+on: [push, pull_request]
+
+env:
+  # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)
+  BUILD_TYPE: Release
+
+jobs:
+  build:
+    # The CMake configure and build commands are platform agnostic and should work equally
+    # well on Windows or Mac.  You can convert this to a matrix build if you need
+    # cross-platform coverage.
+    # See: https://docs.github.com/en/free-pro-team@latest/actions/learn-github-actions/managing-complex-workflows#using-a-build-matrix
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [windows-latest]
+    runs-on: ${{ matrix.os }}
+    name: build-${{ matrix.os }}
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Create Build Environment
+      # Some projects don't allow in-source building, so create a separate build directory
+      # We'll use this as our working directory for all subsequent commands
+      run: cmake -E make_directory ${{github.workspace}}/build
+
+    - name: Configure CMake
+      # Use a bash shell so we can use the same syntax for environment variable
+      # access regardless of the host operating system
+      shell: bash
+      working-directory: ${{github.workspace}}/build
+      # Note the current convention is to use the -S and -B options here to specify source 
+      # and build directories, but this is only available with CMake 3.13 and higher.  
+      # The CMake binaries on the Github Actions machines are (as of this writing) 3.12
+      run: cmake $GITHUB_WORKSPACE -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DLUA_BUILD_AS_CXX=ON
+
+    - name: Build
+      working-directory: ${{github.workspace}}/build
+      shell: bash
+      # Execute the build.  You can specify a specific target with "--target <NAME>"
+      run: cmake --build . --config $BUILD_TYPE
+
+  

.github/workflows/build-windows.yml

@@ -1,6 +1,6 @@
 name: Build Windows
 
-on: [push]
+on: [push, pull_request]
 
 env:
   # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)