Conversation View Color Exception fix #2319

Auriga2 · 2025-06-16T08:23:47Z

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Description of the Change

The issue was caused due to the (sender < colorPositions.length) check in the DefaultConversationColorProvider, where the sender is a vertex id and the colorPositions.length is graph Vertex count. The vertex ids are not in order for graphs created by file importer as it adds 2 vertices for each transaction and then merge unique vertices accordingly. This results in certain vertex Ids > graph Vertex count, failing the above check for certain valid Vertices.

The same scenario can also occur on a graph manually created: On nodes last added after deleting some previously added nodes. (As explained below)

This is the intentional behavior of the code in in ElementStore.java: Vertex/Element ids are not guaranteed to be in order (stored in position2id) , only the Element positions (stored in id2position) are meant to be in order (and each being below Vertex count).

Hence I removed that check as it appears to lack any clear purpose. If we ever need to add a check here, we can validate the Element position instead.

Alternate Designs

If we ever need to add a check here, we can validate the Element position instead.
Initially I tried to rearrange the id2position array, to be similar to a graph opened by constellation, but it doesn't fix the issue on a graph later edited by removing nodes. Also the purpose of 2 arrays in ElementStore is also to facilitate this, making it an incorrect fix.

Why Should This Be In Core?

Fix exception

Benefits

Possible Drawbacks

n/a

Verification Process

Create a graph with 4 nodes, add 4 more nodes and delete the previous 4 nodes. Add a transaction and conversation data and view in conversation view. Verify no exception is thrown.
Verify the exception is not thrown on a graph imported by the file importer as explained in Conversation View Color Exception #2271