How do you mock process.platform in jasmine tests?

You can use Object.defineProperty()

to set the value process.platform

to beforeAll

and then reset the original to afterAll

after the tests are complete.

If you type Object.getOwnPropertyDescriptor(process, "platform")

to get the descriptor

config platform.process

in the node.js console you get this:

{ value: 'darwin',
  writable: false,
  enumerable: true,
  configurable: true }

      

        
        
        
      

    

As you can see the value is process.platform

not writable (see the docs for more information), so you cannot set it uses the assignment operator. but you can override it with Object.defineProperty

.

Jasmine example

describe('test process platform', function(){
    beforeAll(function(){
       this.originalPlatform = process.platform;
       Object.defineProperty(process, 'platform', {  
         value: 'MockOS'
       });
    });

    it(/*test*/);

    ....

    it(/*test*/);

    afterAll(function(){
       Object.defineProperty(process, 'platform', {  
         value: this.originalPlatform
       });
    });
});

      

        
        
        
      

    

Object.defineProperty () docs