$ cd /path/to/meteor-issue-8578
$ meteor npm install
$ meteorThe Meteor application will not start, printing the error message:
=> Errors prevented startup:
While building for web.browser:
main.js:56:15: 'super' outside of function or class (56:15)
While building for os.linux.x86_64:
main.js:56:15: 'super' outside of function or class (56:15)
=> Your application has errors. Waiting for file change.
The bug is dependant on the version of the ecmascript Meteor package. I have
strip all other packages from the application and pinned the packaged version
using @=. At the latest version, 0.7.2, Meteor generates the follow code:
.meteor/local/build/programs/server/app/app.js
/* ... */
var DerivedClass = function (_BaseClass) { //
(0, _inherits3.default)(DerivedClass, _BaseClass); //
//
function DerivedClass() { //
(0, _classCallCheck3.default)(this, DerivedClass); //
return (0, _possibleConstructorReturn3.default)(this, _BaseClass.apply(this, arguments)); //
} //
//
DerivedClass.prototype.foo = function () { //
function foo() { //
var ret = function () { //
return super.foo(); //
}.call(this); // 1
//
_assert(ret, _t.Number, "return value"); //
//
return ret; //
} //
//
return foo; //
}(); //
//
return DerivedClass; //
}(BaseClass); //
/* ... */The tcomb plugin is wrapping DerivedClass#foo() to assert the return value.
But the wrapped method is not getting transpiled. Changing line 8 of mains.js
from foo(): number { to foo() { (i.e., remove the Flow return type
annotation) allows the application to start.
Downgrading the ecmascript package to 0.6.3 generates;
/* ... */
var DerivedClass = function (_BaseClass) { //
(0, _inherits3.default)(DerivedClass, _BaseClass); //
//
function DerivedClass() { //
(0, _classCallCheck3.default)(this, DerivedClass); //
return (0, _possibleConstructorReturn3.default)(this, _BaseClass.apply(this, arguments)); //
} //
//
DerivedClass.prototype.foo = function () { //
function foo() { //
var ret = function () { //
return _BaseClass.prototype.foo.call(this); // 9
}.call(this); // 10
//
_assert(ret, _t.Number, "return value"); //
//
return ret; //
} //
//
return foo; //
}(); //
//
return DerivedClass; //
}(BaseClass); //
/* ... */The wrapped method is correctly transpiled. The application still wont run because of another (now fixed) issue (see issue 8422).