Generates `yarn.lock` from an existing npm-installed `node_modules` folder.
This command assists the migration of projects currently relying on
minimizing the differences between the lockfile and the existing dependency tree
as best as it can.
Many projects currently use
npm shrinkwrap or check their
source control because they have fragile dependency trees. These projects can’t
easily migrate to Yarn, because
yarn install could produce a wildly different
logical dependency tree. Not all trees can be represented by Yarn’s
and some valid trees will be automatically deduped upon install. These nuances
and others present a significant barrier to manual migration.
yarn import aims to alleviate this challenge by generating a
using the versions found inside
node_modules according to normal
resolution rules. In cases where the Yarn resolution mechanism can’t satisfy the
existing dependency tree identically, alerts will be made so that you may manually
review the changes. The existing
node_modules tree will be checked for validity
beforehand, and the resultant lockfile should be
yarn installable without any
surprises (failed compatibility, unresolvable dependencies, auto-dedupes, etc.)
$ yarn import
yarn import vx.x.x success Folder in sync. warning Using version "2.2.4" of "lru-cache" instead of "2.7.3" for "ngstorage > grunt > minimatch" warning Using version "2.0.6" of "readable-stream" instead of "2.2.9" for "ngstorage > karma > chokidar > readdirp" [...] success Saved lockfile. ✨ Done in 11.96s.