A dependency that will first install its deps in one place, then have to have them duped to accommodate a peer dependency from another of its deps.

This models the behavior of [email protected]

gatsby -> ([email protected], @pmmmwh/[email protected])
@pmmmwh/[email protected] -> PEER [email protected]

Initially @pmmmwh/[email protected] is installed alongside gatsby and [email protected] like so:

+-- root
    +-- gatsby
    +-- @pmmmwh/react-refresh-webpack-plugin
    +-- [email protected]

Then, the peerDep from @pmmmwh/react-refresh-webpack-plugin on [email protected] is evaluated, and has nowhere to go except where the [email protected] is already living.

Since we can move [email protected] underneath gatsby, we do so.

In this case:

override -> (a@2, v@1)
v@1 -> PEER(a@1)

This fails to install by default, because the a dep collides.

With --force, we override the peer with the direct root dep, and get:

override
+-- v@1
+-- a@2 (valid for root, invalid for v)
+-- b@2, c@2, ...

When installing override as a dep, we get:

push-dep
+-- v@1
+-- a@1
+-- b@1, c@1, ...
+-- override
    +-- a@2
    +-- b@2, c@2, ...

which is a compliant dependency resolution, where every module gets the version of their dep that they declare.