thordickinson/clipboard_assesment

Code assesment

You've been asked to refactor the attached function to make it easier to read and understand without changing its functionality. For this task, you should:

Write unit tests to cover the existing functionality and ensure that your refactor doesn't break it. We typically use jest, but if you have another library you prefer, feel free to use it.

Refactor the function to be as "clean" and "readable" as possible. There are many valid ways to define those words - use your own personal definitions, but be prepared to defend them. Note that we do like to use the latest JS language features when applicable.

Write up a brief (~1 paragraph) explanation of why you made the choices you did and why specifically your version is more "readable" than the original.

Running the assesment

To run this code use the following commands

npm i
npm run test

To see the coverage use:

npm  test -- --coverage

The tests have a 100% coverage.

----------|---------|----------|---------|---------|-------------------                                                                                                                                    
File      | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s                                                                                                                                     
----------|---------|----------|---------|---------|-------------------
All files |     100 |      100 |     100 |     100 | 
 index.js |     100 |      100 |     100 |     100 | 
----------|---------|----------|---------|---------|-------------------
Test Suites: 1 passed, 1 total
Tests:       4 passed, 4 total

Running original code

The original source code is located in original.js, the updated function is located in index.js, tests are located in index.test.js. If you want to test the original function instead of the modified function, uncomment the first line of the index.test.js file.

//const { deterministicPartitionKey } = require("./original")
const { deterministicPartitionKey } = require("./index")
const { Chance } = require("chance")
const crypto = require("crypto");

Refactor explanation

It could be hard to explain how I did the refactor because what I did was to start removing duplicate logic, but in the end all comes down to determine if the partitionKey is present in the event object or not, and what is it's type. Please read the comments, they explain some of the most important logic facts to remove certain conditionals.

Why is easier to read?

• Is a simple logic without nested blocks
• It does not uses var or let keywords, only const, it makes less bug prune
• It reduces duplicate code
• Reduces validations because some logic conclusions