[BUG] Removing an item from an ObservableList with TrnasformMany and a projection

[dchaib]

Describe the bug
As shown in RolandPheasant/DynamicData.Snippets#5, I have set up an ObservableList with TransFormMany and a projection inside. When I remove an item from the ObservableList, it is not removed from the output. It works with an ObservableCache.

As Roland guessed, the projected item is not removed from the list because it is not found. I believe the culprit is here: https://github.com/RolandPheasant/DynamicData/blob/67367d0068531a94c9ec8a3e197a0b0055f5eca4/DynamicData/List/ChangeAwareList.cs#L519. The call to IndexOf is not using the equalityComparer passed when using TransformMany. I haven't found a way to pass it properly (yet).

Steps To Reproduce
Run the unit tests in https://github.com/RolandPheasant/DynamicData.Snippets.

I'm also happy to send a PR with unit tests here.

Expected behavior
The items should be removed from the output.

Screenshots
n/a

Environment

• OS: Windows
• Version: tested in 6.8 (the issue is still present in the master branch today)
• Device: n/a

Additional context

[glennawatson]

could use https://docs.microsoft.com/en-us/dotnet/api/system.collections.generic.list-1.findindex?redirectedfrom=MSDN&view=netframework-4.8#System_Collections_Generic_List_1_FindIndex_System_Predicate__0__ and use the equality comparer

[dchaib]

The issue is more how to pass the predicate to ChangeAwareList than using it ;-)

[dchaib]

I may have found something. If that's OK, I'll submit a PR tomorrow and we can see if I'm headed in the right direction.

[RolandPheasant]

A PR is welcome. Thanks

[dchaib]

I can confirm that this is fixed in 6.13.1 by #265.