Promise in Javascript

[chai]

/**
 * Add a calculate function to Calculator that matches this specification
 */



describe( "Calculator.calculate", function(){
  var calculator;

  beforeEach( function(){
    calculator = new Calculator();
  } );

  it( "returns a promise", function(){
    var calculating = calculator.calculate( function(){} );
    expect( calculating ).to.be.instanceOf( Promise );
  } );

  it( "resolves when the calculation succeeds", function( done ){
    var calculating = calculator.calculate( function(){
      expect( this ).to.equal( calculator );
      var result = 0;
      result += this.add( 1, 2 );
      result += this.add( 3, 4 );
      return result;
    } );
    calculating.then( function( result ){
      expect( result ).to.equal( 10 );
      done();
    } );
  } );

  it( "rejects when the calculation fails", function( done ){
    var calculating = calculator.calculate();
    calculating.catch( function( result ){
      expect( result ).to.be.NaN;
      done();
    } );
  } );
} );

How to write function for this

[Arulpriya Ramalingam]

Hi Chai, 

 

Thanks for contacting Syncfusion support. 

 

The formulas can be calculated by using the ejCalculate which has the direct support for the basic formulas. You can customize the calculation functions based on your requirement and please refer to the below UG link to know more about the direct formulas, 

 

UG links: https://help.syncfusion.com/js/calculate/supported-formulas/supported-formulas  

 

You can also add your own function to calculate custom formulas based on your requirement by creating and registering the custom function with the application by using CalEngine. Please refer to the below user guide, 

 

UG link: https://help.syncfusion.com/js/calculate/custom-functions  

 

Please let us know that, if you have any concerns. 

 

Regards, 

Arulpriya