Add PosixPluginFrontendSpec

Author: bell-db

bridge/src/test/scala/protocbridge/frontend/PosixPluginFrontendSpec.scala

@@ -0,0 +1,51 @@
+package protocbridge.frontend
+
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.must.Matchers
+import protocbridge.{ExtraEnv, ProtocCodeGenerator}
+
+import java.io.ByteArrayOutputStream
+import scala.sys.process.ProcessIO
+import scala.util.Random
+
+class PosixPluginFrontendSpec extends AnyFlatSpec with Matchers {
+  if (!PluginFrontend.isWindows) {
+    it must "execute a program that forwards input and output to given stream" in {
+      val random = new Random()
+      val toSend = Array.fill(123)(random.nextInt(256).toByte)
+      val toReceive = Array.fill(456)(random.nextInt(256).toByte)
+      val env = new ExtraEnv(secondaryOutputDir = "tmp")
+
+      val fakeGenerator = new ProtocCodeGenerator {
+        override def run(request: Array[Byte]): Array[Byte] = {
+          request mustBe (toSend ++ env.toByteArrayAsField)
+          toReceive
+        }
+      }
+      val (path, state) = PosixPluginFrontend.prepare(
+        fakeGenerator,
+        env
+      )
+      val actualOutput = new ByteArrayOutputStream()
+      val process = sys.process
+        .Process(path.toAbsolutePath.toString)
+        .run(new ProcessIO(writeInput => {
+          writeInput.write(toSend)
+          writeInput.close()
+        }, processOutput => {
+          val buffer = new Array[Byte](4096)
+          var bytesRead = 0
+          while (bytesRead != -1) {
+            bytesRead = processOutput.read(buffer)
+            if (bytesRead != -1) {
+              actualOutput.write(buffer, 0, bytesRead)
+            }
+          }
+          processOutput.close()
+        }, _.close()))
+      process.exitValue()
+      actualOutput.toByteArray mustBe toReceive
+      PosixPluginFrontend.cleanup(state)
+    }
+  }
+}