Allow specific keys to be reverted in unsaved objects

[omairvaiyani]

Currently, the Parse.Object prototype method revert resets ALL unsaved changes. With this PR, specific fields can be provided to the function to allow selective reversion.

Currently:

var person =  ParseObject.fromJSON({
      className: 'Person',
      objectId: 'xxxx',
      name: 'Omair'
 });
person.set('gender', 'male');
person.set('age', 25);
// 'age' is ignored, all fields will be reverted
person.revert('age');
// person -> { name: 'Omair' }

With PR (test cases in commit):
Example 1 (single field):

var person =  ParseObject.fromJSON({
      className: 'Person',
      objectId: 'xxxx',
      name: 'Omair'
 });
person.set('gender', 'male');
person.set('age', 25);
person.revert('age');
// person -> { name: 'Omair', gender: 'male' }

Example 2 (multiple fields):

var person =  ParseObject.fromJSON({
      className: 'Person',
      objectId: 'xxxx',
      name: 'Omair'
 });
person.set('gender', 'male');
person.set('age', 25);
person.set('occupation', 'Doctor');
person.revert(['gender', 'occupation']);
// person -> { name: 'Omair', age: '25' }

Example 3 (no fields, works as now):

var person =  ParseObject.fromJSON({
      className: 'Person',
      objectId: 'xxxx',
      name: 'Omair'
 });
person.set('gender', 'male');
person.set('age', 25);
person.set('occupation', 'Doctor');
person.revert();
// person -> { name: 'Omair' }

[flovilmart]

Can we make this backwards compatible please? Now if no keys are passed the SDK an exception will be thrown.

[omairvaiyani]

@flovilmart I'm getting 584/584 passed on the branch which submitted this PR, is it failing after you attempt a merge with master?

[codecov]

Codecov Report

Merging #565 into master will increase coverage by 0.02%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #565      +/-   ##
==========================================
+ Coverage   85.69%   85.71%   +0.02%     
==========================================
  Files          48       48              
  Lines        3880     3886       +6     
  Branches      882      885       +3     
==========================================
+ Hits         3325     3331       +6     
  Misses        555      555

Impacted Files	Coverage Δ
src/ParseObject.js	88.57% <100%> (+0.08%)	⬆️

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[flovilmart]

LGTM’ thanks!

[flovilmart]

There seems to be issues in the tests / lint. Can you adress those?

[omairvaiyani]

@flovilmart should be good to go now

[flovilmart]

Let’s go! Thanks for bearing with me on this one. It took a while, but it was worth it I believe!