Define CI workflow with Github Actions

.github/workflows/ruby.yml

@@ -0,0 +1,45 @@
+name: Run Unit Tests
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    branches: [ "master" ]
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    name: Test
+    strategy:
+      matrix:
+        ruby-version: ['2.7', '3.0', '3.1']
+        os: ['ubuntu-latest', 'macos-latest']
+    runs-on: ${{ matrix.os }}
+
+    steps:
+    - uses: actions/checkout@v3
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ matrix.ruby-version }}
+        bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+    - name: Run tests
+      run: bundle exec rake test
+
+  test-with-system-lib:
+    name: Test with system library
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v3
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: 3.1
+        bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+    - name: Prepare libjsonnet
+      run: sudo apt install libjsonnet-dev
+    - name: Run tests
+      run: env JSONNET_USE_SYSTEM_LIBRARIES=1 bundle exec rake test

ext/jsonnet/extconf.rb

@@ -77,12 +77,13 @@ def target_object_files
   $LIBPATH = ["#{recipe.path}/lib"] | $LIBPATH
   $CPPFLAGS << " -I#{recipe.path}/include"
 
-  # jsonnet_wrap extension must be linked with c++ stdlib because
-  # the C++ library Rapid YAML is being statically linked.
-  rbconfig = RbConfig::MAKEFILE_CONFIG
-  if rbconfig['LDSHAREDXX']
-    rbconfig['LDSHARED'] = rbconfig['LDSHAREDXX']
-  end
+end
+
+# jsonnet_wrap extension must be linked with c++ stdlib because
+# the C++ library Rapid YAML is being statically linked.
+rbconfig = RbConfig::MAKEFILE_CONFIG
+if rbconfig['LDSHAREDXX']
+  rbconfig['LDSHARED'] = rbconfig['LDSHAREDXX']
 end
 
 abort 'libjsonnet.h not found' unless have_header('libjsonnet.h')

lib/jsonnet/version.rb

@@ -1,3 +1,3 @@
 module Jsonnet
-  VERSION = "0.5.1"
+  VERSION = "0.5.2"
 end