Convert yarn.lock
to package-lock.json
and vice versa.
npm install -g synp
yarn # be sure the node_modules folder dir and is updated
synp --source-file /path/to/yarn.lock
# will create /path/to/package-lock.json
npm install # be sure the node_modules dir exists and is updated
synp --source-file /path/to/package-lock.json
# will create /path/to/yarn.lock
Note: if all you need is to convert in this direction (package-lock.json
=> yarn.lock
), as of 1.7.0, Yarn is able to import its dependency tree from npm’s package-lock.json natively, without external tools. Use the yarn import
command.
const { npmToYarn, yarnToNpm } = require('synp')
const libPath = '/path/to/my/lib'
const stringifiedYarnLock = npmToYarn(libPath)
const stringifiedPackageLock = yarnToNpm(libPath)
Since package-lock.json
and yarn.lock
use different methods in order to deterministically lock down dependency versions, oftentimes they do not contain all the information needed to be purely converted.
For this reason, synp
uses the existing node_modules
directory of the package to determine the package state and assist in the conversion.
For this reason, it is vital to make sure the node_modules
directory of the package is current and was installed by the respective tool (eg. by yarn
if converting to package-lock.json
and by npm
if converting to yarn.lock
).
Bundled dependencies: For various reasons, this tool does not 'play well' with bundled dependencies. This should not be a problem because installing the packages later with the converted file will (by definition) update the proper packages in the file. If this is not the case for you, please open an issue/PR with your use case and I'd be happy to take a look.
Package checksums: Both yarn.lock
and package-lock.json
include package checksums for dependencies. Since npm
is slowly moving to sha-512
checksums which yarn
does not (yet) support, converting to package-lock.json
will result in weaker checksums (that will still work!) and converting to yarn.lock
can sometimes result in a corrupted result file.
Thankfully, this issue is 100% solvable. In npm
one can update the checksums simply by deleting the integrity
field of all or relevant packages. In yarn
this can be solved with the --update-checksums
* flag when installing from the created file.
Format limitations: Some things that can be expressed in one format simply cannot be expressed in the other. These are (to the best of my knowledge) extreme edge cases and should not worry 99% of this tool's intended users. One example is package-lock.json
's ability to translate the same semver string to different versions. (eg. one package requesting version ^1.0.1
of a dependency and receiving 1.0.5
and a different package requesting version ^1.0.1
of the same dependency and receiving 1.0.71
. When translating to yarn.lock
through synp
both will receive the same version).
Optional packages: Like npm
(npm/npm#17722),synp
also has issues with optional dependencies across different platforms. This is because it uses node_modules
as its state, and does not guess about packages that are not installed on the converting platform. Sadly, like the only way to avoid this issue is to perform the conversion on the platform that meets most optional dependencies and update the rest manually. If this is a major issue for you, adding some sort of automatic tooling for this can be discussed.npm
* At the time of this writing, the --update-checksums
flag in yarn
has been merged but not released yet. Please see: yarnpkg/yarn#4860
- checksum mismatch when installing from converted file? In
yarn
use--update-checksums
, innpm
delete theintegrity
field from the offending package (have no fear! This will be updated upon installation). - synp failing or not converting properly - remove the
node_modules
from the package to be converted, install it again (withyarn
if converting topackage-lock.json
ornpm
if converting toyarn.lock
) and runsynp
one more time. - something else? - please open an issue/PR.
MIT