Migrate to a better matching engine

[jamesgeorge007]

As of now meant is made use for finding the closest match to an unknown command which isn't actively maintained anymore.

cli/lib/utils/did-you-mean.js

Line 4 in ab3c62a

var bestSimilarity = meant(scmd, commands).map(function (str) {

A better replacement would be leven

[jamesgeorge007]

@isaacs this would be a good candidate for v7 release. I can work on a PR 👍

[isaacs]

It's relatively isolated, and the core team doesn't have any plans to get to it as a v7 beta release blocker, so yeah! go for it!

• New implementation should have tests, with full coverage of all newly added lib code. (Even if the old implementation doesn't have full coverage, or any tests at all.)
• It would be good to understand why leven would be better. What's "better" about it? Faster? Closer matches? Fewer bugs? (Do those bugs affect us?) etc.

[watilde]

I just noticed #1071 is merged and I'm curious about this part: What's "better" about it? asked by @isaacs and would love to get feedback for further improvements as meant was designed to use in npm at npm/npm#10382. I'm sharing some facts I gathered in the below and still believe that it's hard to find a strong reason why it's already migrated so far.

Size

• leven: 224b
• meant: 288b
  • By deleting test file, .github directory and CHANGELOG as same as leven, it becomes 192b. Can be quickly done if this is a critical.

Last update

• leven: 2 years ago - https://npm.im/leven
• meant: 3 months ago - https://npm.im/meant

Coverage

• leven: 94.59%
• meant: 100%
  Log: https://gist.github.com/watilde/de79754055d627f485a61656f37f72de

Perfomance

• Cannot directly compare as leven does only distance calc and meant does suggestion of a similar command(Refs: added loop by the migration). For the distance calc, it should be almost the same.

Closer matches

• Should be the same as it uses the same algo for calc part.

In addition, I'm happy to migrate meant repository to npm's org + provide npm members with its publish permission on registry if it helps npm community :)

cc @isaacs @jamesgeorge007 @ruyadorno

[watilde]

I wish I could hear back any feedback