Add PosixPluginFrontendSpec

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

@@ -0,0 +1,56 @@
+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 OsSpecificFrontendSpec extends AnyFlatSpec with Matchers {
+
+  protected def testPluginFrontend(frontend: PluginFrontend): Array[Byte] = {
+    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) = frontend.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()
+    frontend.cleanup(state)
+    actualOutput.toByteArray
+  }
+}

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

@@ -0,0 +1,9 @@
+package protocbridge.frontend
+
+class PosixPluginFrontendSpec extends OsSpecificFrontendSpec {
+  if (!PluginFrontend.isWindows) {
+    it must "execute a program that forwards input and output to given stream" in {
+      testPluginFrontend(PosixPluginFrontend)
+    }
+  }
+}

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

@@ -1,38 +1,9 @@
 package protocbridge.frontend
 
-import java.io.ByteArrayInputStream
-
-import protocbridge.{ProtocCodeGenerator, ExtraEnv}
-
-import scala.sys.process.ProcessLogger
-import org.scalatest.flatspec.AnyFlatSpec
-import org.scalatest.matchers.must.Matchers
-
-class WindowsPluginFrontendSpec extends AnyFlatSpec with Matchers {
+class WindowsPluginFrontendSpec extends OsSpecificFrontendSpec {
   if (PluginFrontend.isWindows) {
     it must "execute a program that forwards input and output to given stream" in {
-      val toSend = "ping"
-      val toReceive = "pong"
-      val env = new ExtraEnv(secondaryOutputDir = "tmp")
-
-      val fakeGenerator = new ProtocCodeGenerator {
-        override def run(request: Array[Byte]): Array[Byte] = {
-          request mustBe (toSend.getBytes ++ env.toByteArrayAsField)
-          toReceive.getBytes
-        }
-      }
-      val (path, state) = WindowsPluginFrontend.prepare(
-        fakeGenerator,
-        env
-      )
-      val actualOutput = scala.collection.mutable.Buffer.empty[String]
-      val process = sys.process
-        .Process(path.toAbsolutePath.toString)
-        .#<(new ByteArrayInputStream(toSend.getBytes))
-        .run(ProcessLogger(o => actualOutput.append(o)))
-      process.exitValue()
-      actualOutput.mkString mustBe toReceive
-      WindowsPluginFrontend.cleanup(state)
+      testPluginFrontend(WindowsPluginFrontend)
     }
   }
 }