[BUGFIX lts] Fixes ArrayProxy length reactivity #19111
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Recent refactors for performance left a gap in the reactivity model, specifically for the `length` property of ArrayProxy. We now only use the `CUSTOM_TAG_FOR` API when getting chain tags, which is much better for most `get()` usages since we don't have to do an extra brand check that is not very commonly used. However, the `length` property of ArrayProxy does not have a normal property tag, and it is a native getter which does not entangle the value naturally when accessed via autotracking. This PR sets up the `length` tag eagerly whenever the content of the ArrayProxy changes, and consumes it when the `length` property is accessed. It also does the same thing for the `arrTag`, though that is only used for chain tags. Normally, when the array tag is accessed, it tracks things properly through the `objectAt` API.
rwjblue
approved these changes
Aug 28, 2020
|
@rwjblue is this fix included in Ember 3.20 LTS? |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Recent refactors for performance left a gap in the reactivity model,
specifically for the
lengthproperty of ArrayProxy. We now only usethe
CUSTOM_TAG_FORAPI when getting chain tags, which is much betterfor most
get()usages since we don't have to do an extra brand checkthat is not very commonly used. However, the
lengthproperty ofArrayProxy does not have a normal property tag, and it is a native
getter which does not entangle the value naturally when accessed via
autotracking.
This PR sets up the
lengthtag eagerly whenever the content of theArrayProxy changes, and consumes it when the
lengthproperty isaccessed. It also does the same thing for the
arrTag, though that isonly used for chain tags. Normally, when the array tag is accessed, it
tracks things properly through the
objectAtAPI.Fixes #19105