Error using Lucene.Net.Facet 4.8.0-beta00005 with Xamarin.iOS

I'm using Lucene.Net.Facet 4.8.0-beta00005 in a big Xamarin project.

With Xamarin.Android and Xamarin.UWP it's all right.

But With Xamarin.iOS on device (Ipad), i'm receiving this error:

Attempting to JIT compile method 'Lucene.Net.Support.LurchTable2<Lucene.Net.Facet.Taxonomy.FacetLabel, Lucene.Net.Facet.Taxonomy.Directory.DirectoryTaxonomyReader/Int32Class>:InternalInsert<Lucene.Net.Support.LurchTable2/Add2Info<Lucene.Net.Facet.Taxonomy.FacetLabel, Lucene.Net.Facet.Taxonomy.Directory.DirectoryTaxonomyReader/Int32Class>> (int,Lucene.Net.Facet.Taxonomy.FacetLabel,int&,Lucene.Net.Support.LurchTable`2/Add2Info<Lucene.Net.Facet.Taxonomy.FacetLabel, Lucene.Net.Facet.Taxonomy.Directory.DirectoryTaxonomyReader/Int32Class>&)' while running in aot-only mode. See https://developer.xamarin.com/guides/ios/advanced_topics/limitations/ for more information.

<font color="#d04437">at Lucene.Net.Support.LurchTable2<span class="error">[TKey,TValue]</span>.Insert<span class="error">[T]</span> (TKey key, T& value) <0x2570f48 + 0x000e0> in <063e095c95d945a4ace32ab83d1227eb#2ae0fea9ea4eacaef83bf2e9713bb8ea>:0 at (wrapper unknown) System.Object.gsharedvt_in() at Lucene.Net.Support.LurchTable2<span class="error">[TKey,TValue]</span>.AddOrUpdate (TKey key, TValue addValue, Lucene.Net.Support.KeyValueUpdate2<span class="error">[TKey,TValue]</span> fnUpdate) <0x232824c + 0x0013b> in <063e095c95d945a4ace32ab83d1227eb#2ae0fea9ea4eacaef83bf2e9713bb8ea>:0 at Lucene.Net.Facet.Taxonomy.LRUHashMap2<span class="error">[TKey,TValue]</span>.Put (TKey key, TValue value) <0x2c487f8 + 0x0015b> in <79d3a7b905954d0993025c09c5d087ce#2ae0fea9ea4eacaef83bf2e9713bb8ea>:0 at Lucene.Net.Facet.Taxonomy.Directory.DirectoryTaxonomyReader.GetOrdinal (Lucene.Net.Facet.Taxonomy.FacetLabel cp) <0x2c51970 + 0x0019b> in <79d3a7b905954d0993025c09c5d087ce#2ae0fea9ea4eacaef83bf2e9713bb8ea>:0 at Lucene.Net.Facet.Taxonomy.Int32TaxonomyFacets.GetTopChildren</font> (System.Int32 topN, System.String dim, System.String[] path) <0x2c481dc + 0x0008f> in <79d3a7b905954d0993025c09c5d087ce#2ae0fea9ea4eacaef83bf2e9713bb8ea>:0 at Login.MyMB.Lucene.Client.LuceneArticoliSearcher.GetListaArticoloXRicercaAvanzataConRicercaSemplice (System.Collections.Generic.List1<span class="error">[T]</span> listParametri) <0x224add0 + 0x001bb> in <8f49891e0f0546e185aba7424d294ef7#2ae0fea9ea4eacaef83bf2e9713bb8ea>:0 at Login.MyMB.Lucene.Client.LuceneArticoliSearcher.GetListaArticoloConRicercaSemplice (System.Collections.Generic.List1<span class="error">[T]</span> listParametri) <0x224afbc + 0x0009f> in <8f49891e0f0546e185aba7424d294ef7#2ae0fea9ea4eacaef83bf2e9713bb8ea>:0 at MyMB.Forms.RicercaLucene.RicercaArticoloLucene.GetListaArticoliXRicercaSemplice (Login.MyMB.Interface.IAmbiente ambiente, Login.MyMB.Lucene.Client.LuceneArticoliSearcher las, System.Collections.Generic.List`1<span class="error">[T]</span> ListParametri, System.Boolean isAbilitataRicercaBarcode) <0xe47fc0 + 0x000e7> in <f1bb3149abe145459612794f1a096634#2ae0fea9ea4eacaef83bf2e9713bb8ea>:0 ...............................

At the link https://docs.microsoft.com/it-it/xamarin/ios/internals/limitations , I found the problem cause (I suppose...):

Value types as Dictionary Keys Using a value type as a Dictionary<TKey, TValue> key is problematic, as the default Dictionary constructor attempts to use EqualityComparer<TKey>.Default. EqualityComparer<TKey>.Default, in turn, attempts to use Reflection to instantiate a new type which implements the IEqualityComparer<TKey> interface. This works for reference types (as the reflection+create a new type step is skipped), but for value types it crashes and burns rather quickly once you attempt to use it on the device. Workaround: Manually implement the IEqualityComparer<TKey> interface in a new type and provide an instance of that type to the Dictionary<TKey, TValue> (IEqualityComparer<TKey>) constructor.

So, what can I do? Thank you in advance, Enrico Caltran [phone] <span class="nobr">[e-mail]</span>

JIRA link - [LUCENENET-602] created by enycaltran

[NightOwl888]

This has basically been held open because of https://github.com/NightOwl888/J2N/issues/3, but given the fact this one reporter is no longer interested in a fix and MAUI is right around the corner (which hopefully addresses this), there doesn’t seem to be much sense in spending time on this.

[clambertus]

Is related to: GH-633