Remove extraneous error attributes

Author: sharadraju

lib/errors.js

@@ -448,11 +448,10 @@ function getErr(errorNum) {
     baseText = messages.get(errorNum);
   }
   const errorNumStr = errorNum.toString().padStart(3, '0');
-  const driverCode = `${ERR_PREFIX}-${errorNumStr}`;
-  args[0] = `${driverCode}: ${baseText}`;
+  const code = `${ERR_PREFIX}-${errorNumStr}`;
+  args[0] = `${code}: ${baseText}`;
   const err = new Error(util.format(...args));
-  err.driverErrorNum = errorNum;
-  err.driverCode = driverCode;
+  err.code = code;
   Error.captureStackTrace(err, getErr);
   return err;
 }
@@ -484,14 +483,14 @@ function throwNotImplemented(feature) {
 // Oracle errors and replacing them with driver specific errors.
 //-----------------------------------------------------------------------------
 function transformErr(err, fnOpt) {
-  if (!err.driverCode) {
+  if (!err.code) {
     const pos = err.message.indexOf(":");
     if (pos > 0) {
-      err.driverCode = err.message.substr(0, pos);
-      if (adjustErrorXref.has(err.driverCode)) {
+      err.code = err.message.substr(0, pos);
+      if (adjustErrorXref.has(err.code)) {
         let args = [];
         let driverErrorNum;
-        let driverErrorInfo = adjustErrorXref.get(err.driverCode);
+        let driverErrorInfo = adjustErrorXref.get(err.code);
         if (typeof driverErrorInfo === 'number') {
           driverErrorNum = driverErrorInfo;
         } else {
@@ -503,8 +502,7 @@ function transformErr(err, fnOpt) {
           }
         }
         const newErr = getErr(driverErrorNum, ...args);
-        err.driverCode = newErr.driverCode;
-        err.driverErrorNum = newErr.driverErrorNum;
+        err.code = newErr.code;
         err.message = newErr.message + "\n" + err.message;
       }
     }