Regression: new warning system unable to handle warnings caused by package README.md

[alan-knight]

This version refuses to generate docs for Intl due to changes in

47b60b4

There are two libraries, one for dart:io and one for dart:html which both re-export the same thing, and it considers this ambiguous. Even if it was ambiguous, that's hardly a reason to refuse to generate documentation.

[alan-knight]

@kwalrath

[jcollins-g]

It is actually failing to generate documentation due to a bug where somehow we've managed to try to print a warning for a nonexistent ModelElement, not the ambiguous reexport.

[jcollins-g]

Relevant backtrace:

            stderr:
            warning: ambiguous reexport of locale_list.availableLocalesForDateFormatting, canonicalization candidates: (date_symbol_data_file, date_symbol_data_http_request) (file:///root/.pub-cache/hosted/pub.dartlang.org/intl-0.15.0/lib/src/data/dates/locale_list.dart:6:7)Generation failed: NoSuchMethodError: The method 'warn' was called on null.
            Receiver: null
            Tried calling: warn(Instance of 'PackageWarning', "nerated_file_prefix=<prefix>")
            dart:core                                                                     Object.noSuchMethod
            package:dartdoc/src/markdown_processor.dart 693                               _showWarningsForGenericsOutsideSquareBracketsBlocks.<fn>
            dart:core                                                                     List.forEach
            package:dartdoc/src/markdown_processor.dart 682                               _showWarningsForGenericsOutsideSquareBracketsBlocks
            package:dartdoc/src/markdown_processor.dart 664                               _renderMarkdownToHtml
            package:dartdoc/src/markdown_processor.dart 736                               Documentation.Documentation
            package:dartdoc/src/model.dart 3171                                           Package.documentationAsHtml
            dart:mirrors                                                                  _LocalInstanceMirror.getField
            package:mustache4dart/mustache_context.dart 317                               _ObjectReflectorDeclaration.value
            package:mustache4dart/mustache_context.dart 246                               _ObjectReflector.[]
            package:mustache4dart/mustache_context.dart 132                               _MustacheContext._getActualValue
            package:mustache4dart/mustache_context.dart 105                               _MustacheContext._getMustachContext
            package:mustache4dart/mustache_context.dart 101                               _MustacheContext._getContextForKey
            package:mustache4dart/mustache_context.dart 74                                _MustacheContext._getInThisOrParent
            package:mustache4dart/mustache_context.dart 70                                _MustacheContext.[]
            package:mustache4dart/mustache_context.dart 77                                _MustacheContext._getInThisOrParent
            package:mustache4dart/mustache_context.dart 70                                _MustacheContext.[]
            package:mustache4dart/src/tokens.dart 163                                     _ExpressionToken.apply
            package:mustache4dart/src/tokens.dart 293                                     _StartSectionToken.apply.<fn>
            package:mustache4dart/src/tokens.dart 303                                     _StartSectionToken.forEachUntilEndSection
            package:mustache4dart/src/tokens.dart 293                                     _StartSectionToken.apply
            package:mustache4dart/src/tokens.dart 40                                      Token.call
            package:mustache4dart/src/tmpl.dart 101                                       _Template._write
            package:mustache4dart/src/tmpl.dart 76                                        _Template.call
            package:mustache4dart/src/mustache.dart 14                                    render
            package:mustache4dart/src/tokens.dart 205                                     _PartialToken.apply
            package:mustache4dart/src/tokens.dart 293                                     _StartSectionToken.apply.<fn>
            package:mustache4dart/src/tokens.dart 303                                     _StartSectionToken.forEachUntilEndSection
            package:mustache4dart/src/tokens.dart 293                                     _StartSectionToken.apply
            package:mustache4dart/src/tokens.dart 40                                      Token.call
            package:mustache4dart/src/tmpl.dart 101                                       _Template._write
            package:mustache4dart/src/tmpl.dart 76                                        _Template.call
            package:dartdoc/src/html/html_generator_instance.dart 302                     HtmlGeneratorInstance._build
            package:dartdoc/src/html/html_generator_instance.dart 185                     HtmlGeneratorInstance.generatePackage
            package:dartdoc/src/html/html_generator_instance.dart 94                      HtmlGeneratorInstance._generateDocs
            package:dartdoc/src/html/html_generator_instance.dart 47                      HtmlGeneratorInstance.generate
            package:dartdoc/src/html/html_generator.dart 74                               HtmlGenerator.generate
            package:dartdoc/dartdoc.dart 188                                              DartDoc.generateDocs
            /root/.pub-cache/hosted/pub.dartlang.org/dartdoc-0.11.1/bin/dartdoc.dart 176  main.<fn>
            package:stack_trace                                                           Chain.capture
            /root/.pub-cache/hosted/pub.dartlang.org/dartdoc-0.11.1/bin/dartdoc.dart 175  main
            ===== asynchronous gap ===========================
            dart:async                                                                    _Completer.completeError
            package:dartdoc/src/html/html_generator_instance.dart 56                      HtmlGeneratorInstance.generate
            ===== asynchronous gap ===========================
            dart:async                                                                    Future.Future.microtask
            package:dartdoc/src/html/html_generator_instance.dart 43                      HtmlGeneratorInstance.generate
            package:dartdoc/src/html/html_generator.dart 74                               HtmlGenerator.generate
            package:dartdoc/dartdoc.dart 188                                              DartDoc.generateDocs
            ===== asynchronous gap ===========================
            dart:async                                                                    Future.Future.microtask
            package:dartdoc/dartdoc.dart 126                                              DartDoc.generateDocs
            /root/.pub-cache/hosted/pub.dartlang.org/dartdoc-0.11.1/bin/dartdoc.dart 176  main.<fn>
            ===== asynchronous gap ===========================
            dart:async                                                                    Future.Future.microtask
            /root/.pub-cache/hosted/pub.dartlang.org/dartdoc-0.11.1/bin/dartdoc.dart 175  main.<fn>
            package:stack_trace                                                           Chain.capture
            /root/.pub-cache/hosted/pub.dartlang.org/dartdoc-0.11.1/bin/dartdoc.dart 175  main

[devoncarew]

@jcollins-g, from a brief look, it looks like this is happening when generating docs for the the package - from documentation parsed from the readme.md file.

[jcollins-g]

confirmed: the new warning system has a bug where we don't handle warnings generated by the top level package docs correctly. Should be reasonably easy to fix.