Rule idea: prefer individual per-function modules

[jasonkarns]

Rule suggestion to prefer import uniq from 'lodash.uniq'; over import { uniq } from 'lodash'; to slim bundle sizes and call out explicit uses.

[ganimomer]

Hi, thanks for opening an issue!
This rule is already implemented as import-scope, and its value in the recommended configuration is method, which is what you're describing.

[ganimomer]

However, the plugin currently doesn't handle per-function modules, and can only read imports of files from the lodash modules. (e.g. it recognizes import uniq from 'lodash/uniq' but not import uniq from 'lodash.uniq').
Since it looks like Lodash themselves are going to discontinue per-method packages (second bullet point at the time of writing), I'm not sure the difference is worth implementing.

[jasonkarns]

rule is already implemented as import-scope

as you later mentioned:

doesn't handle per-function modules

the import-scope rule is not at all what I'm suggesting. The per-function module piece is the crux of the rule. Thanks for pointing out the v5 roadmap; I hadn't seen that.

I can only speak as a user, but I'm not sure the potential deprecation would have any near term impact on me or my desire for this rule. Its presence on the roadmap doesn't guarantee the per-function modules actually get discontinued. Nor is there any timeline as to when that might even happen. (The roadmap currently mentions ~2017 for v5 but that was clearly optimistic.) Even if the per-function modules are discontinued (which isn't a certainty) and even if it happens this year (which is unlikely), a lot of teams will still be using lodash v3 or v4 for quite some time to come (years, most likely). So this rule would still be valuable (at least to me) for quite some time.

Indeed, the discontinuation might even make this rule _more_valuable. If the rule could be implemented in such a way as to be configurable between preferring per-function or rejecting per-function, then the rule would be useful both now in the short term (for current usage) and in the future when migrating to v5.

[ganimomer]

That's a good point.
It would take a small infrastructure change, as well, to include per-method packages in the first place.
Would you like to submit a PR?

[jasonkarns]

I would like to but it's unlikely I'll have the time in the next few weeks.

[ganimomer]

I went ahead and implemented this. Fixed in v2.5.0.

[jasonkarns]

sweet, thanks!!