In my TypeScript code, I am compiling to ES2016 and encountered a situation where I was calling two different functions with similar this objects using Function.prototype.call(). To merge both this objects, I decided to use a common object and utilized the ...spread syntax like this:
let selfShared = {
props,
// ...
};
let selfHost = {
...selfShared,
// ...
};
let selfGuest = {
...selfShared,
// ...
};
The intention behind using spread was to be able to overwrite shared properties in either of the this objects if needed. However, when compiled by tsc, it resulted in unexpected behavior as shown below:
let selfShared = {
props
};
let selfHost = Object.assign(Object.assign({}, selfShared), {
// ...
});
// ...
By incorporating my initial code snippet:
let state = undefined;
let attributes = {};
let selfShared = {
props: attributes
};
let selfHost = {
...selfHost,
get state() {
console.log("selfHost get state");
return state;
},
set state(originalStates) {
console.log("selfHost set state");
!state ? state = originalStates : console.error("`this.states` already defined in the host function.");
}
}
The output showed a difference between the expected result and the actual result after compilation by tsc. This discrepancy led to different logs being displayed based on the execution environment.
Furthermore, I tried moving the spread operation to the end of the file, which produced a correct output but limited my ability to override properties from selfShared.
If you can shed some light on why these discrepancies occur with Object.assign and provide any tips to achieve the desired outcome after compilation by tsc, it would be greatly appreciated.