Go: override methods which generates error checks instead of hacking …

…output

translator/src/main/scala/io/kaitai/struct/testtranslator/specgenerators/GoSG.scala

@@ -4,8 +4,8 @@ import _root_.io.kaitai.struct.datatype.{DataType, EndOfStreamError, KSError}
 import _root_.io.kaitai.struct.exprlang.Ast
 import _root_.io.kaitai.struct.languages.GoCompiler
 import _root_.io.kaitai.struct.testtranslator.{Main, TestAssert, TestEquals, TestSpec}
-import _root_.io.kaitai.struct.translators.GoTranslator
-import _root_.io.kaitai.struct.{ClassTypeProvider, RuntimeConfig, StringLanguageOutputWriter, Utils}
+import _root_.io.kaitai.struct.translators.{GoTranslator, TypeProvider}
+import _root_.io.kaitai.struct.{ClassTypeProvider, ImportList, RuntimeConfig, StringLanguageOutputWriter, Utils}
 
 class GoSG(spec: TestSpec, provider: ClassTypeProvider) extends BaseGenerator(spec) {
   /**
@@ -14,15 +14,32 @@ class GoSG(spec: TestSpec, provider: ClassTypeProvider) extends BaseGenerator(sp
     */
   class GoOutputWriter(indentStr: String) extends StringLanguageOutputWriter(indentStr) {
     override def puts(s: String): Unit = {
-      val mangled = s.replace(REPLACER, "r.").replaceAll("return err$", "t.Fatal(err)")
-      super.puts(mangled)
+      super.puts(s.replace(REPLACER, "r."))
+    }
+  }
+
+  /**
+    * Special wrapper around translator that catches all attempts to write error
+    * check and turns it into assertion.
+    */
+  class GoTestTranslator(
+    out: StringLanguageOutputWriter,
+    provider: TypeProvider,
+    importList: ImportList,
+  ) extends GoTranslator(out, provider, importList) {
+    override def outAddErrCheck(): Unit = {
+      out.puts("if err != nil {")
+      out.inc
+      out.puts("t.Fatal(err)")
+      out.dec
+      out.puts("}")
     }
   }
 
   override val out = new GoOutputWriter(indentStr)
   val compiler = new GoCompiler(provider, RuntimeConfig())
   val className = GoCompiler.types2class(List(spec.id))
-  val translator = new GoTranslator(out, provider, importList)
+  val translator = new GoTestTranslator(out, provider, importList)
 
   override def fileName(name: String): String = s"${name}_test.go"