Unexpected Results When Filtering and Mapping Nested Arrays in Angular
I'm converting an old project and I've spent hours debugging this and I'm working with a nested array structure in my Angular application, and I'm running into unexpected results when I try to filter and then map over the array. My data looks something like this: ```typescript const data = [ { id: 1, name: 'John', tags: ['developer', 'angular'] }, { id: 2, name: 'Jane', tags: ['designer', 'css'] }, { id: 3, name: 'Joe', tags: ['developer', 'react'] } ]; ``` I want to filter this array to include only those with the tag 'developer' and then return an array of their names. Here’s how I approached it: ```typescript const developerNames = data .filter(item => item.tags.includes('developer')) .map(item => item.name); ``` The expected output should be `['John', 'Joe']`, but I’m getting `['John']` when I run this. I also added console logs to verify each step: ```typescript console.log('Filtered Data:', data.filter(item => item.tags.includes('developer'))); ``` This outputs the correct filtered objects but the next step doesn't seem to reflect it properly. I tried isolating the question by simplifying the code, and I noticed that if I directly log `data`, it shows the correct array structure. Additionally, I checked for potential issues with reference types, but it seems to be working for basic data types. I’m using Angular version 12, and I'm unsure if this behavior is related to the change detection strategy. Could there be an scenario with how Angular processes these transformations, or am I missing something obvious in the code? My team is using Typescript for this web app. Has anyone dealt with something similar? For reference, this is a production web app. Am I approaching this the right way?