Trim down install size by 5 mb by dropping lodash

[marvinhagemeister]

Feature Request

• I would like to work on this feature!

Is your feature request related to a problem?

Currently every babel installation installs lodash as a dependency, because it is required by @babel/types. This consumes 5MB of disk space for every babel installation.

$ du -h node_modules | sort -h
# ...snip
4.9M	node_modules/lodash
5.9M	node_modules/@babel
7.4M	node_modules/esbuild/bin
7.5M	node_modules/esbuild
8.0M	node_modules/prettier/esm
 17M	node_modules/rxjs
 18M	node_modules/prettier
 54M	node_modules/typescript/lib
 57M	node_modules/typescript
133M	node_modules

$ npm ls lodash
my-project@0.0.1 /Users/marvinhagemeister/dev/github/my-project
└─┬ @babel/core@7.13.14
  └─┬ @babel/types@7.13.14
    └── lodash@4.17.21

Doing a quick grep over babel's repo the lodash package is used for the following tasks:

• Get the last element in an array

  • babel/packages/babel-plugin-transform-function-name/test/fixtures/function-name/modules-2/input.mjs

    Line 9 in 9808d25

    return last(this.tokens.get(key))

• Check if a value is an object that was created via the Object constructor

  • babel/packages/babel-types/src/converters/valueToNode.ts

    Line 98 in 6b39baf

    if (isPlainObject(value)) {

• Deeply clone a value

  • babel/eslint/babel-eslint-plugin/test/rules/no-invalid-this.js

    Line 55 in 7bc72bb

    const thisPattern = cloneDeep(pattern);

  • babel/packages/babel-register/src/node.js

    Line 45 in 6b39baf

    ...deepClone(transformOpts),

• Debounce a function

  • babel/packages/babel-cli/src/babel/dir.js

    Line 138 in 98aa72c

    const logSuccess = debounce(

A small footprint is desireable as it makes docker images smaller which in turn lead to faster deployments.

Describe the solution you'd like

Smaller install size. I did start a small ~4kb lodash clone a while back, but it's missing isPlainObject. The rest should work out of the box. Functions like getting the last element of an array should probably be just inlined though.

Describe alternatives you've considered.

Documentation, Adoption, Migration Strategy

[babel-bot]

Hey @marvinhagemeister! We really appreciate you taking the time to report an issue. The collaborators on this project attempt to help as many people as possible, but we're a limited number of volunteers, so it's possible this won't be addressed swiftly.

If you need any help, or just have general Babel or JavaScript questions, we have a vibrant Slack community that typically always has someone willing to help. You can sign-up here for an invite."

[nicolo-ribaudo]

Yeah at least last, isPlainObject and debounce can be easily inlined.

[hzoo]

Agreed, we're happy to take a PR to inline these especially since a lot of them are only used once/in one place. Did a few of these kinds of PRs earlier #13057

For the particular thing about @babel/core, we can inline isPlainObject and remove it since it's the main reason