package.json中指定的依赖项

Question

Let's say I have a client-side app (say an Ember application)

I define my application's package.json with the various dependencies.

    {
    name: "my-app",
    dependencies: {
       "dep1" : "1.0.0"
    },
    devDependencies: {
       "devDep1" : "1.0.0"
    }
    }

My question is

1. Do I not have to worry about the dependencies which "dep1" itself would have? Meaning not define those sub-dependencies in my package.json, coz they'll be taken care of in the package.json which "dep1" itself would define?

2. Any situations where we would define the dependencies in our own app..eg say our app uses "jquery" while even dep1 requires "jquery" ...Ideally, we would not define "jquery" in our own package.json in this case...But any use case where we might have to like different version required by our app...in this case, how would the overriding behavior work meaning what version gets considered?

3. Is this handled similarly across all package managers like npm, bower?

PS: Any additional info in an Ember engine environment would be useful as well (meaning when using a Parent app with child addon, etc.)

Answer 1

• You don't have to worry about any dependent packages. They are read from the package's package.json that you have required and installed.
• This is consistent across all package managers.

--- UPDATE ---

npm dependencies are nested. This means that each package can have a separate version of the same package as a dependency. In your case, if a package requires "jquery" and you want to use a different version of "jquery", you can install any version as per your need and that will be the only version available to you and not any other version required by any dependency of your package.

Answer 2

package.json or npm uses nested-dependencies which mean a dependency can have a own dependency on sub-dependency and so on. npm will resolve those dependency by itself. This allows different modules to have different version of same dependency.