Aliases
Aliases let you install packages with custom names.
Let's assume you use lodash
all over your project. There is a bug in lodash
that breaks your project. You have a fix but lodash
won't merge it. Normally
you would either install lodash
from your fork directly (as a git-hosted
dependency) or publish it with a different name. If you use the second solution
you have to replace all the requires in your project with the new dependency
name (require('lodash')
=> require('awesome-lodash')
). With aliases, you
have a third option.
Publish a new package called awesome-lodash
and install it using lodash
as
its alias:
pnpm add lodash@npm:awesome-lodash
No changes in code are needed. All the requires of lodash
will now resolve to
awesome-lodash
.
Sometimes you'll want to use two different versions of a package in your project. Easy:
pnpm add lodash1@npm:lodash@1
pnpm add lodash2@npm:lodash@2
Now you can require the first version of lodash via require('lodash1')
and the
second via require('lodash2')
.
This gets even more powerful when combined with hooks. Maybe you want to replace
lodash
with awesome-lodash
in all the packages in node_modules
. You can
easily achieve that with the following .pnpmfile.cjs
:
function readPackage(pkg) {
if (pkg.dependencies && pkg.dependencies.lodash) {
pkg.dependencies.lodash = 'npm:awesome-lodash@^1.0.0'
}
return pkg
}
module.exports = {
hooks: {
readPackage
}
}