Fix basic image tests and add them to CI

Author: larskanis

.github/workflows/ci.yml

@@ -74,6 +74,12 @@ jobs:
           bundle exec rake clean clobber
           bundle exec rake gem:${PLATFORM}
 
+      - name: Basic tests on the generated image
+        env:
+          TEST_PLATFORM: ${{ matrix.platform }}
+        run: |
+          bundle exec rake test
+
       - name: Upload binary gem
         uses: actions/upload-artifact@v3
         with:

test/test_environment_variables.rb

@@ -8,7 +8,9 @@
 
 class TestEnvironmentVariables
   module Common
-    IMAGE_NAME = "larskanis/rake-compiler-dock-mri-x86-mingw32:#{RakeCompilerDock::IMAGE_VERSION}"
+    TEST_PLATFORM = ENV["TEST_PLATFORM"] || "x64-mingw-ucrt"
+    DOCKERHUB_USER = ENV['DOCKERHUB_USER'] || "larskanis"
+    TEST_IMAGE_NAME = "#{DOCKERHUB_USER}/rake-compiler-dock-mri-#{TEST_PLATFORM}:#{RakeCompilerDock::IMAGE_VERSION}"
 
     def rcd_env
       self.class.instance_variable_get("@rcd_env") || begin
@@ -49,7 +51,7 @@ class UsingWrapper < Test::Unit::TestCase
 
     def invocation(command)
       idir = File.join(File.dirname(__FILE__), '../lib')
-      "#{RbConfig::CONFIG['RUBY_INSTALL_NAME']} -I#{idir.inspect} bin/rake-compiler-dock bash -c '#{command}'"
+      "RCD_PLATFORM=#{TEST_PLATFORM} #{RbConfig::CONFIG['RUBY_INSTALL_NAME']} -I#{idir.inspect} bin/rake-compiler-dock bash -c '#{command}'"
     end
 
     def test_HOST_RUBY_PLATFORM
@@ -61,7 +63,7 @@ def test_HOST_RUBY_VERSION
     end
 
     def test_IMAGE
-      assert_equal IMAGE_NAME, rcd_env['RCD_IMAGE']
+      assert_equal TEST_IMAGE_NAME, rcd_env['RCD_IMAGE']
     end
 
     def test_PWD
@@ -73,7 +75,7 @@ class AsIfContinuousIntegration < Test::Unit::TestCase
     include Common
 
     def invocation(command)
-      "docker run -it #{IMAGE_NAME} bash -c '#{command}'"
+      "docker run -it #{TEST_IMAGE_NAME} bash -c '#{command}'"
     end
   end
 end

test/test_parallel_docker_build.rb

@@ -65,6 +65,6 @@ def test_common_files
   end
 
   def read_df(fn)
-    File.read("tmp/docker/#{fn}").each_line.map(&:lstrip).join
+    File.read(File.join(@tmpdir, "/tmp/docker", fn)).each_line.map(&:lstrip).join
   end
 end