Cannot use map keys in ng-model that are not strings

[davidpolberger]

Referencing a map value in ng-model where the keys of the map are not strings results in an exception being thrown. Consider this markup:

<form ng-repeat="field in cmp.fields">
  <div contenteditable ng-model="cmp.map[field]"></div>
</form>

(Where the type of cmp.fields is Map<Field, String>.)

Error, including stack trace:

type 'String' is not a subtype of type 'Field' of 'key'.

STACKTRACE:
#0      _HashMap.[]= (dart:collection-patch/collection_patch.dart:95)
#1      setKeyed (package:angular/core/parser/utils.dart:93:11)
#2      AccessKeyed.assign (package:angular/core/parser/eval_access.dart:47:35)
#3      DynamicExpression.assign (package:angular/core/parser/dynamic_parser.dart:59:32)
#4      DynamicExpression.assign (package:angular/core/parser/dynamic_parser.dart:60:7)
#5      assign (package:angular/core/parser/syntax.dart:78:47)
#6      NgModel.modelValue= (package:angular/directive/ng_model.dart:80:34)
#7      NgModel.viewValue= (package:angular/directive/ng_model.dart:77:27)
#8      InputTextLikeDirective.processValue.<anonymous closure> (package:angular/directive/ng_model.dart:204:34)
#9      relaxFnArgs.<anonymous closure> (package:angular/utils.dart:72:40)
#10     Scope.$eval (package:angular/core/scope.dart:701:43)
#11     Scope.$apply.<anonymous closure> (package:angular/core/scope.dart:765:21)
#12     _rootRun (dart:async/zone.dart:683)
#13     _ZoneDelegate.run (dart:async/zone.dart:417)
#14     _onRun.<anonymous closure> (package:angular/core/zone.dart:61:56)
#15     NgZone._onRunBase (package:angular/core/zone.dart:49:16)
#16     _onRun (package:angular/core/zone.dart:61:15)
#17     _ZoneDelegate.run (dart:async/zone.dart:417)
#18     _CustomizedZone.run (dart:async/zone.dart:627)
#19     NgZone.run (package:angular/core/zone.dart:143:27)
#20     Scope.$apply (package:angular/core/scope.dart:761:21)
#21     InputTextLikeDirective.processValue (package:angular/directive/ng_model.dart:204:19)
#22     InputTextLikeDirective.InputTextLikeDirective.<anonymous closure> (package:angular/directive/ng_model.dart:196:23)
#23     _rootRunUnary (dart:async/zone.dart:700)
#24     _ZoneDelegate.runUnary (dart:async/zone.dart:426)
#25     _onRunUnary.<anonymous closure> (package:angular/core/zone.dart:65:61)
#26     NgZone._onRunBase (package:angular/core/zone.dart:49:16)
#27     _onRunUnary (package:angular/core/zone.dart:65:15)
#28     _ZoneDelegate.runUnary (dart:async/zone.dart:426)
#29     _CustomizedZone.runUnary (dart:async/zone.dart:631)
#30     _BaseZone.runUnaryGuarded (dart:async/zone.dart:546)
#31     _BaseZone.bindUnaryCallback.<anonymous closure> (dart:async/zone.dart:572)

The problem is in package:angular/core/parser/utils.dart, specifically in the getKeyed() and setKeyed() methods, which treat instances of the List and Map classes specially. For maps, the existing code assumes that keys are always strings:

/// Set a keyed element in the given [object].
setKeyed(object, key, value) {
  if (object is List) {
    int index = key.toInt();
    if (object.length <= index) object.length = index + 1;
    object[index] = value;
  } else if (object is Map) {
    object["$key"] = value; // toString dangerous?
  } else {
    object[key] = value;
  }
  return value;
}

The fix is simple: simply remove the Map-specific code:

/// Set a keyed element in the given [object].
setKeyed(object, key, value) {
  if (object is List) {
    int index = key.toInt();
    if (object.length <= index) object.length = index + 1;
    object[index] = value;
  } else {
    object[key] = value;
  }
  return value;
}

(This fix needs to be applied to getKeyed() as well.)

This fix works well locally -- should I submit a pull request?

[mhevery]

Fixed by: 03f0a4c