Compiler error on dynamic import

[jakzo]

JS supports using import as a function. When shadow-cljs encounters one of these, the Closure compiler fails.

Example

:requireing a JS file with the following code:

export default function() {
  import("hello").then(function(mod) {
    alert(mod.default);
  });
}

will fail when compiling with this error:

shadow-cljs - config: /.../shadow-dynamic-import-issue/shadow-cljs.edn  cli version: 2.7.17  node: v11.6.0
shadow-cljs - starting ...
[:dynamic] Compiling ...
errors in file: /.../shadow-dynamic-import-issue/node_modules/dynamic-import/index.js
{:js-str-offsets [], :js-esm false, :js-imports [], :js-invalid-requires [], :goog-provides [], :js-language "es3", :goog-module nil, :js-warnings [], :resource-name "node_modules/dynamic-import/index.js", :js-requires [], :js-errors [{:line 2, :column 2, :message "'}' expected"}], :goog-requires [], :tag :shadow.build.npm/errors, :uses-global-buffer false}
ExceptionInfo: errors in file: /.../shadow-dynamic-import-issue/node_modules/dynamic-import/index.js
        clojure.core/ex-info (core.clj:4739)
        clojure.core/ex-info (core.clj:4739)
        shadow.build.npm/get-file-info* (npm.clj:530)
        ...

Repro: https://github.com/jakzo/shadow-dynamic-import-issue

[thheller]

Dynamic import is not currently supported by the Closure Compiler (or shadow-cljs).

Some initial support was added recently but I'm not yet sure how final support will look. I don't think this is a good idea to begin with so we'll see how it turns out.

[FalseProtagonist]

Sorry, just to check that I'm interpreting these issues correctly - it's now supported by Google Closure but not planned to be supported in shadow-cljs (?)

[thheller]

Depends. I have not tested enough yet. Currently blocked by ClojureScript being incompatible with the latest Closure Compiler.

[coatlicue89]

Hi, seems dynamic imports are supported by the Closure Compiler https://github.com/google/closure-compiler/wiki/JS-Modules#dynamic-import-expressions . But not working for me actually. Whats the status? can I help?

[thheller]

Please open a new ticket with a reproducible repo for something that may not work. This is not exactly a "small topic". So, without knowing what are trying to do I can't comment on the status.

[coatlicue89]

Issue created #1084 thanks for your response.