PaulUithol/Backbone-relational

previous attributes broken when another attributes changed in handler.

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#485 opened on Aug 18, 2014

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bughelp wanted

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Description

Scenario:

  • has model with several listeners on some property propA
  • one of the listener change another property propB.
  • In rest of handlers for propA previousAttributes contains new value of propA instead old one.

In case of usage regular Model instead of RelationalModel previousAttributes contains old value as expected.

sample: http://jsfiddle.net/4ohq1tho/1

this cause several issues like https://github.com/kmalakoff/knockback/issues/121

Contributor guide

Research direction
Inspect the change event handling in Backbone relational to understand when previousAttributes is captured; check if the bug occurs because the snapshot is taken after one handler mutates another property, thus mutating the model state before later handlers read previousAttributes.
Tech stack
javascript
Domain
frontend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
JavaScriptBackbone
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
60