question: Angular Warning: CommonJS or AMD dependencies can cause optimization bailouts.

Upon adding class-validator to my Angular project, I get this warning when building:

WARNING in /node_modules/class-validator/esm2015/decorator/common/IsLatLong.js depends on 'validator'. CommonJS or AMD dependencies can cause optimization bailouts.

I am not using the @IsLatLong() decorator so I’m assuming the tree shaking/webpack will ignore this, but I just wanted to put a question out there for reassurance!

[mcelotti]

I had the same problem and, according to https://angular.io/guide/build#configuring-commonjs-dependencies, I added “validator” to “allowedCommonJsDependencies” inside my “angular.json” file:

            "allowedCommonJsDependencies": [
              "validator"
            ]

This fixed the issue.

[ThorstenKunz]

I will go forward and close this as we have nothing to fix this.

I don’t think this is correct. According to validator.js github site they do provide tree-shakeable ES imports. You have to replace the import paths a little bit:

import isDivisibleByValidator from 'validator/lib/isDivisibleBy'; with this import isDivisibleByValidator from 'validator/es/lib/isDivisibleBy';

Then the WARNING should go away and projects using class-validator will be able to get optimized better.