Mongoose document: Execute hook manually for testing
Okay, here’s what we did at the end. We replaced the $__save function with a no operation implementation:
// overwrite the $__save with a no op. function, // so that mongoose does not try to write to the databasetestDoc.$__save = function(options, callback) { callback(null, this);};This prevents hitting the database, but the pre hook obviously still gets called.
testDoc.save(function(err, doc) { expect(doc.property).to.eql('foo_modified'); done();});Mission accomplished.
As of Mongoose 5.9, using the $__save override doesn't seem to work, so here is a replacement that doesn't require you to call the save() method directly:
const runPreSaveHooks = async (doc) => { return new Promise((resolve, reject) => { doc.constructor._middleware.execPre("save", doc, [doc], (error) => { error ? reject(error) : resolve(doc); }); });};await runPreSaveHooks(testDoc);expect(doc.property).to.eql('foo_modified');