@console/assessment-js

JS Assessment

This will assess your familiarity with vanilla Javascript. It will mainly test your ability and understanding working with collections.

It will cover the following concepts:

• built in array methods for iteration
• iteration techniques for including / excluding / changing data
• hash maps / lookup tables
• higher order functions / first class functions
• type safety
• object equality, compare by reference vs value

Requirements

• You are not allowed to use any libraries in your solutions
• You are not allowed to modify the test file, only ./index.js
• es6/es2015 is preferred, but you will not be penalised for using es5

What to do

• Fill out ./index.js to make the tests in __tests__/index.js pass
• Run the tests once with npm run test
• Run the tests continuously with npm run test/watch while you develop

Scoring

• Each problem has an associated score. You can get partial points even if your solution does not pass the test.
• If you're struggling with finding a solution, try and add comments explaining your approach, as this can earn you points as well

Assessment Criteria

• Declarative solutions are preferred over imperative ones
• Try to avoid introducing local variables unless required
• Clean, readable solutions are preferred over performant ones. No need to optimise prematurely.
• New data is preferred over mutations, unless otherwise specified

Problem 1 - stripPrivateProperties - 2 points

Given an array of objects, create a new array where the objects inside don't include the supplied properties.

Note: object mutation is fine here.

Problem 2 - excludeByProperty - 2 points

Given an array of objects, create a new array which excludes objects based on a supplied property.

Problem 3 - sumDeep - 3 points

Compute sums based on deep properties.

Problem 4 - applyStatusColor - 4 points

Create a function which creates an array of objects where each object includes its matching status code. The association between colors and status codes are supplied as the first argument where the keys identify the colors, and the values are arrays of status codes matching the color. You can assume that a status code can only belong to one color.

Constraints

• Since there are so many status codes - we want a scalable solution, so you are not allowed to use if or switch statements to find the appropriate color.

Problem 5 - createGreeting - 2 points

Figure out what to do from the test.

Problem 6 - sanitizeUser - 4 points

Here your task is to refactor the code to make it safer, more readable and more performant. The code you see uses some pretty poor coding practices. When refactoring, bear in mind:

• The user supplied to the function comes from a dirty API
  • We can not assume that all properties exist
  • The type of a property is not guaranteed
    • i.e. for varying users, the same properties could have different types

Problem 7 - setDefaults - 3 points

Create a function which adds default properties to objects in an array if required.