node.js - Clearing require cache

Question

I am trying to delete a module from cache as suggested here.

In the documentation we read:

require.cache

• Object

Modules are cached in this object when they are required. By deleting a key value from this object, the next require will reload the module.

So, I created a file named 1.js that contains a single line:

module.exports = 1;

Then I require it via node shell:

ionicabizau@laptop:~/Documents/test$ node
> require("./1")
1
> require.cache
{ '/home/ionicabizau/Documents/test/1.js': 
   { id: '/home/ionicabizau/Documents/test/1.js',
     exports: 1,
     parent: 
      { id: 'repl',
        exports: [Object],
        parent: undefined,
        filename: '/home/ionicabizau/Documents/test/repl',
        loaded: false,
        children: [Object],
        paths: [Object] },
     filename: '/home/ionicabizau/Documents/test/1.js',
     loaded: true,
     children: [],
     paths: 
      [ '/home/ionicabizau/Documents/test/node_modules',
        '/home/ionicabizau/Documents/node_modules',
        '/home/ionicabizau/node_modules',
        '/home/node_modules',
        '/node_modules' ] } }
# edited file to export 2 (module.exports = 2;)
> require.cache = {}
{}
> require.cache
{}
> require("./1") // supposed to return 2
1

So, why does require("./1") return 1 when my file contains module.exports = 2 and the cache is cleared?

Doing some debugging I saw that there is a Module._cache object that is not cleared when I do require.cache = {}.

Answer 1

require.cache is just an exposed cache object reference, this property is not used directly, so changing it does nothing. You need to iterate over keys and actually delete them.