Error using core-scaffold from polymer JS in the latest Polymer Dart release

StackOverflow https://stackoverflow.com//questions/24018020

Question

After hearing that Polymer JS components should work out of the box, which they don't, I went ahead and tried using some Polymer JS elements in my project.

I needed to remove a few files like demo.html, metadata.html and index.html from all the JS components and replacing with . This is so that the polymer transformer wouldn't include the unwanted and unneeded files, plus make sure it uses the dart polymer.html file to prevent it being loaded twice.

I included the core-scaffold component, and got this error when running pub serve in the latest Dart Editor.

Build error:
Transform ScriptCompactor on gcanvas|web/index.html threw error: The null object does not have a method '>'.

NoSuchMethodError: method not found: '>'
Receiver: null
Arguments: [7]
dart:core-patch/object_patch.dart 45                                            Object.noSuchMethod
http://127.0.0.1:39312/packages/polymer_expressions/parser.dart 99:30           Parser._parseBinary
http://127.0.0.1:39312/packages/polymer_expressions/parser.dart 71:72           Parser._parsePrecedence
http://127.0.0.1:39312/packages/polymer_expressions/parser.dart 43:52           Parser._parseExpression
http://127.0.0.1:39312/packages/polymer_expressions/parser.dart 29:28           Parser.parse
http://127.0.0.1:39312/packages/polymer_expressions/parser.dart 12:56           parse
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 524:25  _HtmlExtractor._addExpression
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 509:23  _HtmlExtractor._processNormalElement.<fn>
dart:collection-patch/collection_patch.dart 957                                 _HashMap&&_LinkedHashMapMixin.forEach
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 495:28  _HtmlExtractor._processNormalElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 453:43  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 465:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 465:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 462:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 465:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 465:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 465:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 32:52                 TreeVisitor.visitDocument
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 16:52                 TreeVisitor.visit
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 187:61  _extractUsesOfMirrors
dart:async/zone.dart 730                                                        _rootRunUnary
dart:async/zone.dart 864                                                        _RootZone.runUnary
dart:async/future_impl.dart 488                                                 _Future._propagateToListeners.handleValueCallback
dart:async/future_impl.dart 571                                                 _Future._propagateToListeners
dart:async/future_impl.dart 555                                                 _Future._propagateToListeners.handleWhenCompleteCallback.<fn>
dart:async/zone.dart 730                                                        _rootRunUnary
dart:async/zone.dart 864                                                        _RootZone.runUnary
dart:async/future_impl.dart 488                                                 _Future._propagateToListeners.handleValueCallback
dart:async/future_impl.dart 571                                                 _Future._propagateToListeners
dart:async/future_impl.dart 331                                                 _Future._completeWithValue
dart:async/future_impl.dart 393                                                 _Future._asyncComplete.<fn>
dart:async/schedule_microtask.dart 23                                           _asyncRunCallbackLoop
dart:async/schedule_microtask.dart 32                                           _asyncRunCallback
dart:isolate-patch/isolate_patch.dart 128                                       _RawReceivePortImpl._handleMessage

dart:core                                                                       Object.noSuchMethod
http://127.0.0.1:39312/packages/polymer_expressions/parser.dart 99:30           Parser._parseBinary
http://127.0.0.1:39312/packages/polymer_expressions/parser.dart 71:72           Parser._parsePrecedence
http://127.0.0.1:39312/packages/polymer_expressions/parser.dart 43:52           Parser._parseExpression
http://127.0.0.1:39312/packages/polymer_expressions/parser.dart 29:28           Parser.parse
http://127.0.0.1:39312/packages/polymer_expressions/parser.dart 12:56           parse
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 524:25  _HtmlExtractor._addExpression
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 509:23  _HtmlExtractor._processNormalElement.<fn>
dart:collection                                                                 _HashMap&&_LinkedHashMapMixin.forEach
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 495:28  _HtmlExtractor._processNormalElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 453:43  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 465:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 465:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 462:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 465:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 465:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 39:50                 TreeVisitor.visitElement
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 465:25  _HtmlExtractor.visitElement
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 12:50                 TreeVisitor.visit
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 24:49                 TreeVisitor.visitChildren
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 30:48                 TreeVisitor.visitNodeFallback
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 32:52                 TreeVisitor.visitDocument
http://127.0.0.1:39312/packages/html5lib/dom_parsing.dart 16:52                 TreeVisitor.visit
http://127.0.0.1:39312/packages/polymer/src/build/script_compactor.dart 187:61  _extractUsesOfMirrors
dart:isolate                                                                    _RawReceivePortImpl._handleMessage
Build completed with 1 errors.
[web] GET /index.html => Could not find asset gcanvas|web/index.html.
[web] GET /favicon.ico => Could not find asset gcanvas|web/favicon.ico.

I tracked it down to the component core-header-panel, by excluding, then one by one including components found in core-scaffold, till it failed again.

Does anyone know where is this method '>'? And what is null? Unless I want to give up on using core-scaffold, this is a blocker. Anyway pasted below is the contents of the bower.json file and the pubspec.yaml, in case it helps.

pubspec.yaml

name: gcanvas
version: 0.0.5
author: James Hurford
description: Canvasing App for doorknocking campaigns.
environment:
  sdk: '>=1.0.0 <2.0.0'
dependencies:
  browser_detect: any
  csvparser: any
  http: any
  http_server: any
  lawndart: any
  mime: any
  polymer: any
  postgresql: any
  route: any
  uuid: any
dev_dependencies:
  scheduled_test: any
transformers:
- polymer:
    entry_points:
    - web/index.html

bower.json

{
  "name": "gcanvas",
  "version": "0.0.0",
  "authors": [
    "James Hurford"
  ],
  "private": true,
  "ignore": [
    "**/.*",
    "node_modules",
    "bower_components",
    "test",
    "tests"
  ],
  "dependencies": {
    "x-tag-imports": "x-tag/x-tag-imports",
    "polymer-ui-tabs": "polymer/polymer-ui-tabs#~0.3.0",
    "core-scaffold": "polymer/core-scaffold#~0.3.1"
  },
  "resolutions": {
    "platform": ">=0.3.0 <1.0.0"
  }
}

Thanks

Was it helpful?

Solution

From looking at the code where the exception was thrown it seems the Polmyer transformer tries to process the HTML file and the binding expressions. This looks like a bug or missing feature in polymer_expressions and possible the Dart Polymer transformer. I suspect this code in polymer-header-panel <div id="mainContainer" flex?="{{mode !== 'cover'}}" on-scroll="{{scroll}}"> is causing the exception at the unknown operator !==

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