Can't ignore part of file causing polymer-expression-parse-error

[jsilvermist]

I'm getting a [polymer-expression-parse-error] error I'm not really sure what to do about when trying to build with a file that looks like this:

<dom-module id="sl-backup-script">
  <template>
    <style include="prism-theme-default">...</style>

    <prism-highlighter></prism-highlighter>
    <marked-element>
      <div slot="markdown-html"></div>
      <script type="text/markdown">
        ...
        if [[ -n $last_backup ]]; then
          if [[ -z `find $file_output/* -maxdepth 0 -type d -mtime -7 -not -name "*-latest"` ]]; then
            file_date=`date -r $file_output/$last_backup $date_format`
            mv $file_output/$last_backup $file_output/$file_date
          else
            rm -rf $file_output/$last_backup
          fi
        fi
        ...
      </script>
    </marked-element>
  </template>
  <script>...</script>
</dom-module>

And when it gets to the part of:

if [[ -n $last_backup ]]; then
  if [[ -z `find $file_output/* -maxdepth 0 -type d -mtime -7 -not -name "*-latest"` ]]; then

It crashes with the error:

D:\Development\silverlinkz>polymer build
info:    Clearing build\ directory...
info:    (es6-unbundled) Building...

        if [[ -n $last_backup ]]; then
                 ~

src/code/backup-script/sl-backup-script.html(72,17) error [polymer-expression-parse-error] - Unexpected token $last_backup

          if [[ -z `find $file_output/* -maxdepth 0 -type d -mtime -7 -not -name "*-latest"` ]]; then
                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

src/code/backup-script/sl-backup-script.html(74,16) warning [invalid-polymer-expression] - The - operator is only supported for writing negative numbers.
error:   Promise rejection: Error: 1 error(s) occurred during build.
error:   Error: 1 error(s) occurred during build.
    at BuildAnalyzer._done (C:\Users\Jason\AppData\Roaming\npm\node_modules\polymer-cli\node_modules\polymer-build\lib\analyzer.js:265:36)
    at BuildAnalyzer.<anonymous> (C:\Users\Jason\AppData\Roaming\npm\node_modules\polymer-cli\node_modules\polymer-build\lib\analyzer.js:225:26)
    at Generator.next (<anonymous>)
    at fulfilled (C:\Users\Jason\AppData\Roaming\npm\node_modules\polymer-cli\node_modules\polymer-build\lib\analyzer.js:17:58)
    at <anonymous>

This all works fine except when trying to build, is there some way to ignore part of a file to prevent this parsing issue?

[jsilvermist]

@usergenic Shouldn't this not be parsed for bindings since it's inside a script (also style now too), and not be touched at all since it's a script with the type text/markdown?

[TimvdLippe]

For reference, a similar issue has recently been fixed in the Polymer core with bindings: https://github.com/Polymer/polymer/pull/4841

For here, the simplest check would be to check the type for text/javascript and ignore if it is not.

[usergenic]

Yeah this seems like something that needs work in PolymerAnalyzer, though it is unclear whether we want to ignore script tags or if a lower error severity would suffice. Thoughts, @rictic @justinfagnani ?

[justinfagnani]

The Analyzer needs to match the semantics of Polymer itself. If Polymer is interpreting the [[ ... ]] in the markdown above, then it's entirely correct for the Analyzer to complain about bad syntax.

Now that https://github.com/Polymer/polymer/pull/4841 is merged, the Analyzer needs to take that into account (though for what versions, or all versions, of Polymer is a good question).

An immediate workaround is to escape one of the left-square brackets as [

[jsilvermist]

An immediate workaround is to escape one of the left-square brackets as [

Doesn't work, it just shows up in the document as [ instead of [.

Current workaround is far from ideal, which is to add a space, and then run a gulp script after polymer build like so:

'use strict';

const gulp = require('gulp');
const replace = require('gulp-replace');

gulp.task('default', () => {
  // Transform backup-script post-build to bypass polymer-cli parse errors
  return gulp.src('build/**/sl*backup-script.html')
    .pipe(replace('if [ [', 'if [['))
    .pipe(gulp.dest('build/'));
});

[stale[bot]]

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