How to filter an array inside an object?-CodePudding

I'm struggling to filter an array inside an object on a condition (in my case filter if value1 <> value2 and toggle is true)

myObject = { 
    value: 1, 
    capacitiesArray: [{value1: 10, value2: 10}, {value1: 10, value2: 20}] 
}

so my output should be

filtredObject = { 
    value: 1, 
    capacitiesArray: [{value1: 10, value2: 20}] 
}

I created this function called "filterObject", that have in parameter "myObject" et "toggle"(if toggle true then filer "capacitiesArray" else don't filter "capacitiesArray"

I tried to do it by doing that, but it's doesn't seem to work :(

I think I'm having an issue with object mutation

function filterObject(myObject: MyObject, toggle: boolean): MyObject {
if(toggle) {
  const rows = myObject.capacitiesArray; 
  const capacitiesArray = rows.filter((row) => row.value1 !== row.value2); 
  myObject.capacitiesArray = capacitiesArray; 
  return myObject; 
  } 
return myObject; 
}

Here's a link for the code to unit test the function https://stackblitz.com/edit/github-test-run-draft-gczdsg?file=src/app/app.component.spec.ts

in app.component.spec.ts

the second test "filterRowOnCosCoeValue should filter operationalCapacities when toggle on" passes (that's fine, since the expected result is "expectedOperationalNoticeMock")

but it should not pass when I provide "operationalNoticeMock" as expected object result (it passes anyways giving a false positive result)

Any help/suggestion ? :) Thank you!

EDIT: add details for false positive test passing

CodePudding user response：

This is as you pointed out due to object mutation issues. As you probably know Objects in Javascript are by reference. If you mutate the Object a simple comparison wont show you any cahnge, so you have to perform a deep comparison.

Try the following in your test:

  it('filterRowOnCosCoeValue should filter operationalCapacities when toggle on', () => {
    const expectedResult = JSON.stringify(operationalNoticeMock);
    const result = JSON.stringify(filterObject(operationalNoticeMock, true));
    expect(result).toEqual(expectedResult);
  });

I have forked the stackblitz

EDIT

Right now the test is failing but if you replace the value with expectedOperationalNoticeMock will pass.

Change this line:

const expectedResult = JSON.stringify(operationalNoticeMock);

By this one:

const expectedResult = JSON.stringify(expectedOperationalNoticeMock);

It will pass as expected.

CodePudding user response：

I tried it and it works for me:

let obj = {
  h: "any",
  arr: [{
    value1: 10,
    value2: 10
  }, {
    value1: 10,
    value2: 20
  }]
}

let rows = obj.arr;
obj.arr = rows.filter(v => v.value1 !== v.value2);

console.log(obj);