canReflect.assignDeep doesn't deep copy DefineMap

[green3g]

Code Sample:

import { Reflect, DefineMap } from "//unpkg.com/can@5/core.mjs";


const a = {};
const b = new DefineMap({
	prop: {
		test: 'hello'
	}
});

Reflect.assignDeep(a, b);

console.log(a.prop === b.prop); // true

https://codepen.io/anon/pen/rQOBPx?editors=0011

Objects nested inside a define map won't be deep copied, instead they will still reference the original object.

I may be wrong on this, but I would expect a to be a plain object with all of the properties from b copied over, not referenced.

[cherifGsoul]

The fix that I made seems correct, but it breaks can-map and can-define, any help how to solve this is much appreciated!

[chasenlehara]

Which can-define and can-map tests are failing with your change?

[cherifGsoul]

@chasenlehara those tests:
https://github.com/canjs/can-map/blob/master/can-map_test.js#L108
https://github.com/canjs/can-map/blob/master/can-map_test.js#L585
https://github.com/canjs/can-define/blob/master/test/test-define-only.js#L398

[cherifGsoul]

I tried to find a solution by overwriting can.assignDeep in can-map but canReflect.assignDeep is called in the setup function to assign defaultValues to data object, the data has not assignDeep Symbol.
Is this a breaking change or we need to add assignDeep Symbol to can-map data?

[justinbmeyer]

Can you describe what you did a bit more in depth. Ideally with snippets of the source you are taking about.

[cherifGsoul]

In my comment above I'm talking about this snippets in can-map:

var defaultValues = this._setupDefaults(obj);
var data = assign(canReflect.assignDeep({}, defaultValues), obj);

Fixing this issue will break can-map instantiation and tests like this will be broken.
cc @justinbmeyer

[cherifGsoul]

I fixed the two broken tests for can-map caused by the fix of this issue:
https://github.com/canjs/can-map/blob/master/can-map_test.js#L108
https://github.com/canjs/can-map/blob/master/can-map_test.js#L585

Here is the changes:

• in can-reflect I changed assignDeepMap to fix this issue, now with canReflect.assignDeep plain objects are copied not referenced

• To avoid the breaking change in can-map I added a assignDeepMap Symbol which has the behavior referencing Map objects in this PR

It remains the broken test in can-define.

[cherifGsoul]

The last changes/release in can-define make it works with my fix for this issue, now we just need to review/merge and release this can-map PR before releasing the fix of this issue.