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This library has been deprecated. A better alternative can found athttps://www.npmjs.com/package/proxyquire.

mock-require is useful if you want to mockrequire statements in Node.js. I wrote it because I wanted something with a straight-forward API that would let me mock anything, from a single exported function to a standard library.

varmock=require('mock-require');mock('http',{request:function(){console.log('http.request called');}});varhttp=require('http');http.request();// 'http.request called'

path:String

The module that you want to mock. This is the same string you would pass in if you wanted torequire the module.

This path should be relative to the current file, just as it would be if you were torequire the module from the current file. mock-require is smart enough to mock this module everywhere it is required, even if it's required from a different file using a different relative path.

mockExport :object/function

The function or object you want to be returned fromrequire, instead of thepath module's exports.

mockExport :string

The module you want to be returned fromrequire, instead of thepath module's export. This allows you to replace modules with other modules. For example, if you wanted to replace thefs module with thepath module (you probably wouldn't, but if you did):

mock('fs','path');require('fs')===require('path');// true

This is useful if you have a mock library that you want to use in multiple places. For example:

test/spy.js:

module.exports=function(){return'this was mocked';};

test/a_spec.js:

varmock=require('mock-require');mock('../some/dependency','./spy');...

test/b_spec.js:

varmock=require('mock-require');mock('../some/other/dependency','./spy');...

path:String

The module you that you want to stop mocking. This is the same string you would pass in if you wanted torequire the module.

This will only modify variables used aftermock.stop is called. For example:

varmock=require('mock-require');mock('fs',{mockedFS:true});varfs1=require('fs');mock.stop('fs');varfs2=require('fs');fs1===fs2;// false

This function can be used to remove all registered mocks without the need to remove them individually usingmock.stop().

mock('fs',{});mock('path',{});varfs1=require('fs');varpath1=require('path');mock.stopAll();varfs2=require('fs');varpath2=require('path');fs1===fs2;// falsepath1===path2;// false

path:String

The file whose cache you want to refresh. This is useful if you're trying to mock a dependency for a file that has already been required elsewhere (possibly in another test file). Normally, Node.js will cache this file, so any mocks that you apply afterwards will have no effect.reRequire clears the cache and allows your mock to work.

varfs=require('fs');varfileToTest=require('./fileToTest');mock('fs',{});// fileToTest is still using the unmocked fs modulefileToTest=mock.reRequire('./fileToTest');// fileToTest is now using your mock

Note that if the file you are testing requires dependencies that in turn require the mock, those dependencies will still have the unmocked version. You may want toreRequire all of your dependencies to ensure that your mock is always being used.

varfs=require('fs');varotherDep=require('./otherDep')// requires fs as a dependencyvarfileToTest=require('./fileToTest');// requires fs and otherDep as a dependencymock('fs',{});// fileToTest and otherDep are still using the unmocked fs moduleotherDep=mock.reRequire('./otherDep');// do this to make sure fs is being mocked consistentlyfileToTest=mock.reRequire('./fileToTest');

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