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ko.observableArray()プロパティで拡張されたエンティティのインポート中にエラーが発生[]し、コンストラクターで単純な配列型として拡張されました。

var customerCtor = function () {
    this.extendedProp = ko.observable(true);
    //this.extendedArray = ko.observableArray(); // causes error: Cannot write a value to a ko.computed unless you specify a 'write' option. If you wish to read the current value, don't pass any parameters.
    this.extendedArray = []; // this works just fine
  };

Breeze v1.3.6 DocCode: exportImportTests.js "キャッシュ全体をローカルに隠して復元する" を出発点としてテストを作成しました。新しいテストは次のとおりです。

test("w/extended Customer, stash entire cache locally and restore", 3, function () {
  var em1 = newEm();

  var store = em1.metadataStore;
  // extend Customer with observables 
  var customerCtor = function () {
    this.extendedProp = ko.observable(true);
    this.extendedArray = ko.observableArray(); // causes error: Cannot write a value to a ko.computed unless you specify a 'write' option. If you wish to read the current value, don't pass any parameters.
    //this.extendedArray = []; // but this will work just fine?
  };

  store.registerEntityTypeCtor("Customer", customerCtor);

  var expected = testData.primeTheCache(em1);
  // grab first Customer, push value onto extendedArray prop
  var custEntity = em1.getEntities(expected.customerType)[0];
  custEntity.extendedArray().push('some-value');  // even when defined as [], Breeze re-writes field as ko.observable

  var exportData = em1.exportEntities();

  var stashName = "stash_everything";
  window.localStorage.setItem(stashName, exportData);

  var importData = window.localStorage.getItem(stashName);
  var em2 = new EntityManager(); // virginal - so register ctor on this instance
  var store2 = em2.metadataStore;
  store2.registerEntityTypeCtor("Customer", customerCtor);
  em2.importEntities(importData);

  var entitiesInCache = em2.getEntities();
  var restoreCount = entitiesInCache.length;
  equal(restoreCount, expected.entityCount,
      "should have restored expected number of all entities");

  var restoredCustomer = em2.getEntities(expected.customerType)[0];
  ok(restoredCustomer.extendedProp(), 'extended property present');
  ok(restoredCustomer.extendedArray().length > 0, 'extended Array present and has data');
});

Anem2.importEntities(importData);は次のエラーをスローします。

Error: Cannot write a value to a ko.computed unless you specify a 'write' option. If you wish to read the current value, don't pass any parameters.
at Error (<anonymous>)
at h [as extendedArray] (http://localhost:47595/Scripts/knockout-2.2.1.js:44:167)
at ctor.initializeEntityPrototype.proto.setProperty (http://localhost:47595/Scripts/breeze.debug.js:14634:31)
at updateTargetPropertyFromRaw (http://localhost:47595/Scripts/breeze.debug.js:13062:24)
at aspectName (http://localhost:47595/Scripts/breeze.debug.js:13025:13)
at Array.forEach (native)
at updateTargetFromRaw (http://localhost:47595/Scripts/breeze.debug.js:13023:19)
at em._inKeyFixup (http://localhost:47595/Scripts/breeze.debug.js:12601:17)
at Array.forEach (native)
at importEntityGroup (http://localhost:47595/Scripts/breeze.debug.js:12568:28)

Breeze は常にコンストラクタ フィールドを書き換えるため (私の場合は KO の場合)、as 定義は機能し[]ます。しかし、プロパティが事前に定義されているのに、なぜこれが起こるのかわかりませんか?

誰かがこれに遭遇したか、どこかでドキュメントのメモを見逃したことがありますか?

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