Clean Code Rulebook

Variable Names

Variable name with meaning:

Wrong

let x = priceValidation(0);

Right

let isPriceValid = priceValidation(0);

Singular and Plural

Wrong

let person = ['John', 'Mary', 'Luke'];
let persons = 'Adam';

Right

let persons = ['John', 'Mary', 'Luke'];
let person = 'Adam';

Functions are Verbs

Wrong

const total = (a, b) => a + b;

Right

const calcTotal = (a, b) => a + b;

To Be or Not Be...

Wrong

const greenColor = ( color === 'green');

Right

const isGreenColor = ( color === 'green');

WTH is 273.15

Wrong

const kelvinDegrees = 24 + 273.15;

Right

const celsiusDegrees = 24;
const kelvinScale = 273.5;
const kelvinDegrees = celsiusDegrees + kelvinScale;

Please, call me by full name.

Wrong

const names = [ 'John Smith', 'Mary Smith', 'Luke Smith' ];
const namesWithLastNameSmith = names.filter ( (x) => { 
//code ...
});

Right

const names = [ 'John Smith', 'Mary Smith', 'Luke Smith' ];
const namesWithLastNameSmith = names.filter ( (name) => { 
//code ...
});

Errors, Warnings, and Info.

Something Wrong?

Wrong

const isOver18YearsOld = age > 17;
if( isOver18YearsOld ) {
  showMessage('Is Something wrong :(';
}

Right

const isOver18YearsOld = age > 17;
if( isOver18YearsOld ) {
  showMessage('Sorry, You must be over 18 years old.';
}

Debuggin in Production :O

Wrong

throw new Error(‘Unexpected Error’);

Right

throw new Error(‘someFile.js:someFunction: undefined value in variable’);

I keep updating this RuleBook.