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Using console in JS for better testing

In this article i’d like to share my experience of using some console features for debugging purposes. Let’s start with the definition what is a console?

Console – is a browsers built-in debugger. Obviously you know about it using console.log a lot. But what if I tell you that behind the console there are more then you can realized. Just running **console.log(console)** will show you a lot of methods that can be using along with console.

**console.assert()**

Writes an error message if the assertion is false. If the assertion is true, nothing happens.

 
let userLogged = true
console.log('user logged:' + userLogged)
console.assert(userLogged, '1  user is not logged')
userLogged = false
console.log('user logged:' + userLogged)
console.assert(userLogged, '2 user is not logged')

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**console.clear()**

To clear the console.

**console.table()**

Displays tabular data as a table.

 
function employee (name, profession) {
  this.name = name
  this.profession = profession
} 
let james = new employee('James', 'Developer')
console.table(james)

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**console.group()**

To group things together with a label.

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**console.groupCollapsed()**

The same as group, but creates the new block collapsed.

**console.count()**

Logs the number of times that this particular call to count has been called.

 
console.count('test'); // "test: 1"
console.count('js'); //"js: 1"
console.count('test'); //"test: 2"

**console.countReset()**

To reset a counter for a label.

**console.time()**

Also you can keep track the amount of time between your console.logs by using **console.time()**

It will start the timer, and then calling **console.timelog()** will log the amount of time elapsed since last timer started. And **console.timeEnd()** to stop the timer.

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Using string substitutions passing a string to one of the console object’s methods that accepts a string (**%s** outputs as string)

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Pass **%c** to console to apply CSS style.

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And don’t forget about **console.error()**, which will print an error to the console.

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The post Using console in JS for better testing appeared first on Apiumhub.


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