test: share gem install logic and exercise library usage

Author: zah

gems/native-tracer/lib/codetracer_ruby_recorder.rb

@@ -0,0 +1,19 @@
+require 'fileutils'
+require 'rbconfig'
+
+ext_dir = File.expand_path('../ext/native_tracer/target/release', __dir__)
+dlext = RbConfig::CONFIG['DLEXT']
+lib = File.join(ext_dir, "codetracer_ruby_recorder.#{dlext}")
+unless File.exist?(lib)
+  alt = %w[so bundle dylib dll]
+         .map { |ext| File.join(ext_dir, "libcodetracer_ruby_recorder.#{ext}") }
+         .find { |path| File.exist?(path) }
+  if alt
+    begin
+      File.symlink(alt, lib)
+    rescue StandardError
+      FileUtils.cp(alt, lib)
+    end
+  end
+end
+require lib

test/test_tracer.rb

@@ -62,49 +62,75 @@ def program_args(base)
     end
   end
 
-  def test_gem_installation
+  def run_gem_installation_test(gem_bin, gem_module)
     Dir.chdir(File.expand_path('..', __dir__)) do
-      system('just', 'build-extension', exception: true)
-
-      dlext = RbConfig::CONFIG['DLEXT']
-      ext_path = File.join('gems', 'native-tracer', 'ext', 'native_tracer', 'target', 'release', "codetracer_ruby_recorder.#{dlext}")
-      FileUtils.rm_f(ext_path)
+      gem_dir = case gem_bin
+                when 'codetracer-ruby-recorder'
+                  File.join('gems', 'native-tracer')
+                when 'codetracer-pure-ruby-recorder'
+                  File.join('gems', 'pure-ruby-tracer')
+                else
+                  raise ArgumentError, "unknown gem #{gem_bin}"
+                end
+
+      if gem_bin == 'codetracer-ruby-recorder'
+        system('just', 'build-extension', exception: true)
+        dlext = RbConfig::CONFIG['DLEXT']
+        ext_path = File.join(gem_dir, 'ext', 'native_tracer', 'target', 'release', "codetracer_ruby_recorder.#{dlext}")
+        FileUtils.rm_f(ext_path)
+      end
 
       Dir.mktmpdir('gemhome') do |gem_home|
-        gem_build = IO.popen(%w[gem -C gems/native-tracer build codetracer-ruby-recorder.gemspec], err: [:child, :out]) { |io| io.read }
+        gemspec = Dir[File.join(gem_dir, '*.gemspec')].first
+        gem_build = IO.popen(%W[gem -C #{gem_dir} build #{File.basename(gemspec)}], err: [:child, :out]) { |io| io.read }
         gem_file = gem_build.lines.grep(/File:/).first.split.last
-        gem_file = File.expand_path(File.join('gems/native-tracer', gem_file))
+        gem_file = File.expand_path(File.join(gem_dir, gem_file))
 
         env = { 'GEM_HOME' => gem_home, 'GEM_PATH' => gem_home, 'PATH' => "#{gem_home}/bin:#{ENV['PATH']}" }
         system(env, 'gem', 'install', '--local', gem_file, exception: true)
 
-        out_dir = File.join('test', 'tmp', 'gem_install')
+        out_dir = File.join('test', 'tmp', "gem_install_#{gem_bin.tr('-', '_')}")
         FileUtils.rm_rf(out_dir)
-        stdout, stderr, status = Open3.capture3(env, 'ruby', '-S', 'codetracer-ruby-recorder', '--out-dir', out_dir, File.join('test', 'programs', 'addition.rb'))
-        raise "native_trace failed: #{stderr}" unless status.success?
+        stdout, stderr, status = Open3.capture3(env, 'ruby', '-S', gem_bin, '--out-dir', out_dir, File.join('test', 'programs', 'addition.rb'))
+        raise "#{gem_bin} failed: #{stderr}" unless status.success?
         assert_equal "3\n", stdout
         assert File.exist?(File.join(out_dir, 'trace.json'))
+
+        out_dir_lib = File.join('test', 'tmp', "gem_install_#{gem_bin.tr('-', '_')}_lib")
+        FileUtils.rm_rf(out_dir_lib)
+        script = <<~RUBY
+          require '#{gem_module}'
+          recorder = RubyRecorder.new
+          puts 'start trace'
+          recorder.disable_tracing
+          puts 'this will not be traced'
+          recorder.enable_tracing
+          puts 'this will be traced'
+          recorder.disable_tracing
+          puts 'tracing disabled'
+          recorder.flush_trace('#{out_dir_lib}')
+        RUBY
+        script_path = File.join('test', 'tmp', "use_#{gem_bin.tr('-', '_')}.rb")
+        File.write(script_path, script)
+        stdout, stderr, status = Open3.capture3(env, 'ruby', script_path)
+        raise "#{gem_module} library failed: #{stderr}" unless status.success?
+        expected_out = <<~OUT
+          start trace
+          this will not be traced
+          this will be traced
+          tracing disabled
+        OUT
+        assert_equal expected_out, stdout
+        assert File.exist?(File.join(out_dir_lib, 'trace.json'))
       end
     end
   end
 
-  def test_pure_gem_installation
-    Dir.chdir(File.expand_path('..', __dir__)) do
-      Dir.mktmpdir('gemhome') do |gem_home|
-        gem_build = IO.popen(%w[gem -C gems/pure-ruby-tracer build codetracer_pure_ruby_recorder.gemspec], err: [:child, :out]) { |io| io.read }
-        gem_file = gem_build.lines.grep(/File:/).first.split.last
-        gem_file = File.expand_path(File.join('gems/pure-ruby-tracer', gem_file))
-
-        env = { 'GEM_HOME' => gem_home, 'GEM_PATH' => gem_home, 'PATH' => "#{gem_home}/bin:#{ENV['PATH']}" }
-        system(env, 'gem', 'install', '--local', gem_file, exception: true)
+  def test_gem_installation
+    run_gem_installation_test('codetracer-ruby-recorder', 'codetracer_ruby_recorder')
+  end
 
-        out_dir = File.join('test', 'tmp', 'gem_install_pure')
-        FileUtils.rm_rf(out_dir)
-        stdout, stderr, status = Open3.capture3(env, 'ruby', '-S', 'codetracer-pure-ruby-recorder', '--out-dir', out_dir, File.join('test', 'programs', 'addition.rb'))
-        raise "pure_trace failed: #{stderr}" unless status.success?
-        assert_equal "3\n", stdout
-        assert File.exist?(File.join(out_dir, 'trace.json'))
-      end
-    end
+  def test_pure_gem_installation
+    run_gem_installation_test('codetracer-pure-ruby-recorder', 'codetracer_pure_ruby_recorder')
   end
 end