628061c501
* Add new.target transform * Catch new.target under only an arrow function * More unsupported reflect.construct cases * Fix node 4 test * Do not transform Methods * More tests * Properly setup function inheritance test * Tests tests tests * Fix ES6 class's new.target * Remove expected output thats supposed to throw.
65 lines
1.6 KiB
JavaScript
65 lines
1.6 KiB
JavaScript
export default function({ types: t }) {
|
|
return {
|
|
name: "transform-new-target",
|
|
|
|
visitor: {
|
|
MetaProperty(path) {
|
|
const meta = path.get("meta");
|
|
const property = path.get("property");
|
|
const { scope } = path;
|
|
|
|
if (
|
|
meta.isIdentifier({ name: "new" }) &&
|
|
property.isIdentifier({ name: "target" })
|
|
) {
|
|
const func = path.findParent(path => {
|
|
if (path.isClass()) return true;
|
|
if (path.isFunction() && !path.isArrowFunctionExpression()) {
|
|
if (path.isClassMethod({ kind: "constructor" })) {
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
return false;
|
|
});
|
|
|
|
if (!func) {
|
|
throw path.buildCodeFrameError(
|
|
"new.target must be under a (non-arrow) function or a class.",
|
|
);
|
|
}
|
|
|
|
const { node } = func;
|
|
if (!node.id) {
|
|
if (func.isMethod()) {
|
|
path.replaceWith(scope.buildUndefinedNode());
|
|
return;
|
|
}
|
|
|
|
node.id = scope.generateUidIdentifier("target");
|
|
}
|
|
|
|
const constructor = t.memberExpression(
|
|
t.thisExpression(),
|
|
t.identifier("constructor"),
|
|
);
|
|
|
|
if (func.isClass()) {
|
|
path.replaceWith(constructor);
|
|
return;
|
|
}
|
|
|
|
path.replaceWith(
|
|
t.conditionalExpression(
|
|
t.binaryExpression("instanceof", t.thisExpression(), node.id),
|
|
constructor,
|
|
scope.buildUndefinedNode(),
|
|
),
|
|
);
|
|
}
|
|
},
|
|
},
|
|
};
|
|
}
|