Support chained Dart method/prop calls

[valerauko]

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Is your feature request related to a problem? Please describe.

In ClojureDart you can chain property/method calls. The following is valid:

(require '["package:flutter/material.dart" :as m :refer [MainAxisAlignment]])
m/EdgeInsets.zero
(m/EdgeInsets.symmetric .horizontal 10 .vertical 5)
MainAxisAlignment.center

Describe the solution you'd like

Teach clj-kondo to recognize this syntax and warn only about the first bit (eg if a class name is used but never referred)

(require '["package:flutter/material.dart" :as m])
EdgeInsets.zero ;; this should be m/EdgeInsets.zero

Describe alternatives you've considered

Currently we either ignore the unresolved symbol warnings where the chaining is used, or unpack the chaining like below

;; instead of ns-alias/SomeClass.prop.prop
(.-prop (.-prop ns-alias/SomeClass))

Additional context

I'd love to help implementing this, but I have no idea where to start

[borkdude]

In normal Clojure(Script) you can write this as:

(.. m/EdgeInsets.symmetric (horizontal 10) (vertical 5))

Why does ClojureDart need to deviate from this?

[valerauko]

Those are not separate methods, but named parameters to the EdgeInsets constructor symmetric

https://api.flutter.dev/flutter/painting/EdgeInsets/EdgeInsets.symmetric.html

[valerauko]

For example

;; :require ["package:flutter/material.dart" :as m]
(=
 (m/WidgetsBinding.instance.removeObserver some-observer)
 (.removeObserver (.-instance m/WidgetsBinding) some-observer)
 (-> m/WidgetsBinding .-instance (.removeObserver some-observer)))

[borkdude]

I understand those interop forms, but I don't understand your remark about "those are not separate methods" and then saying "for example" where no named parameters occur in the example, or am I missing something?

[borkdude]

ClojureDart could support:

(m/EdgeInsets.symmetric :.horizontal 10 :.vertical 5)

or similar for named parameters, has this been considered?

[borkdude]

I misunderstood the issue. MainAxisAlignment.center gives a false positive, but the rest works.

When you lint the above as CLJS it does work:

clj-kondo --lint tmp/dart.cljd --lang cljs
linting took 41ms, errors: 0, warnings: 0

So we just have to convince clj-kondo to do the same as ClojureScript when using ClojureDart

[valerauko]

Yeah it's very similar to the js/console.log kind of cljs syntax. Gotta add a possible refer to the mix though (the false positive you mention)