Implement doByteArrayNonLiteral for Lua and C++

jvm/src/test/scala/io/kaitai/struct/translators/TranslatorSpec.scala

@@ -854,12 +854,12 @@ class TranslatorSpec extends AnyFunSpec {
     describe("to do type enforcement") {
       // type enforcement: casting to non-literal byte array
       full("[0 + 1, 5].as<bytes>", CalcIntType, CalcBytesType, ResultMap(
-        CppCompiler -> "???",
+        CppCompiler -> "std::string({static_cast<char>(0 + 1), static_cast<char>(5)})",
         CSharpCompiler -> "new byte[] { 0 + 1, 5 }",
         GoCompiler -> "[]uint8{0 + 1, 5}",
         JavaCompiler -> "new byte[] { 0 + 1, 5 }",
         JavaScriptCompiler -> "new Uint8Array([0 + 1, 5])",
-        LuaCompiler -> "???",
+        LuaCompiler -> "string.char(0 + 1, 5)",
         PerlCompiler -> "pack('C*', (0 + 1, 5))",
         PHPCompiler -> "pack('C*', 0 + 1, 5)",
         PythonCompiler -> "struct.pack('2B', 0 + 1, 5)",

shared/src/main/scala/io/kaitai/struct/translators/CppTranslator.scala

@@ -113,12 +113,23 @@ class CppTranslator(provider: TypeProvider, importListSrc: CppImportList, import
         // TODO: C++14
       }
     } else {
-      throw new RuntimeException("C++ literal arrays are not implemented yet")
+      throw new RuntimeException("literal arrays are not yet implemented for C++98 (pass `--cpp-standard 11` to target C++11)")
     }
   }
 
   override def doByteArrayLiteral(arr: Seq[Byte]): String =
     "std::string(\"" + Utils.hexEscapeByteArray(arr) + "\", " + arr.length + ")"
+  override def doByteArrayNonLiteral(values: Seq[Ast.expr]): String = {
+    // It is assumed that every expression produces integer in the range [0; 255]
+    if (config.cppConfig.useListInitializers) {
+      "std::string({" + values.map(value => s"static_cast<char>(${translate(value)})").mkString(", ") + "})"
+    } else {
+      // TODO: We need to produce an expression, but this is only possible using
+      // initializer lists or variadic templates (if we use a helper function),
+      // both of which are only available since C++11
+      throw new RuntimeException("non-literal byte arrays are not yet implemented for C++98 (pass `--cpp-standard 11` to target C++11)")
+    }
+  }
 
   override def genericBinOp(left: Ast.expr, op: Ast.operator, right: Ast.expr, extPrec: Int) = {
     (detectType(left), detectType(right), op) match {

shared/src/main/scala/io/kaitai/struct/translators/LuaTranslator.scala

@@ -67,10 +67,14 @@ class LuaTranslator(provider: TypeProvider, importList: ImportList) extends Base
 
   override def doBoolLiteral(n: Boolean): String =
     if (n) "true" else "false"
+
   override def doArrayLiteral(t: DataType, value: Seq[Ast.expr]): String =
     "{" + value.map((v) => translate(v)).mkString(", ") + "}"
   override def doByteArrayLiteral(arr: Seq[Byte]): String =
     "\"" + decEscapeByteArray(arr) + "\""
+  override def doByteArrayNonLiteral(values: Seq[Ast.expr]): String =
+    // It is assumed that every expression produces integer in the range [0; 255]
+    "string.char(" + values.map(translate).mkString(", ") + ")"
 
   override def doLocalName(s: String) = s match {
     case Identifier.ITERATOR => "_"