Tools: Linter warns on the dynamic import operator

[fwielstra]

We have a setup where we pull our project though Babel's stage 2 preset, which amongst other things allows for dynamically loading html via JS (see screenshot). However, at the moment this causes polymer lint to error with error [parse-error] - 'import' and 'export' may only appear at the top level. Since it's a parse error, we can't disable this rule in our polymer.json file. Would it be possible to allow for this syntax or disable this error?

[omair100]

You can use System.import to get around it - if that helps.

[jrunning]

This is a polymer-analyzer issue. The problem is that Espree, the JavaScript parser polymer-analyzer uses, doesn't support dynamic imports and has no plans to support them until they're part of the ECMAScript standard. (From the Espree README: “In general, we do not support experimental JavaScript features. We may make exceptions from time to time depending on the maturity of the features.”)

As far as I can tell the only solution would be for polymer-analyzer to switch to a different parser like Acorn (which has a plugin for dynamic imports) or Esprima. I don't know how likely that is to happen, but you should definitely file a polymer-analyzer issue so they know there's demand for it.

[usergenic]

We have added support for this in the upcoming polymer-analyzer 3.0.0 branch. Coming soon.

[rictic]

This is a case where our existing behavior is in error. I'd call that a bug.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.