ECMAScript = {
  compileForShell(command) {
    const babelOptions = Babel.getDefaultOptions();
    delete babelOptions.sourceMap;
    delete babelOptions.sourceMaps;
    babelOptions.ast = false;
    return Babel.compile(command, babelOptions).code;
  }
};

ECMAScript = {
  compileForShell(command) {
    const babelOptions = Babel.getDefaultOptions();
    babelOptions.sourceMap = false;
    babelOptions.ast = false;
    return Babel.compile(command, babelOptions).code;
  }
};

--- 
+++ 
@@ -1,8 +1,7 @@
 ECMAScript = {
   compileForShell(command) {
     const babelOptions = Babel.getDefaultOptions();
-    delete babelOptions.sourceMap;
-    delete babelOptions.sourceMaps;
+    babelOptions.sourceMap = false;
     babelOptions.ast = false;
     return Babel.compile(command, babelOptions).code;
   }
Stop passing babelOptions.sourceMap when compiling `meteor shell` commands.
