Description

areMapsEqual compares values via next[key] without verifying key presence. If prev has {a: null} and next has {b: null} (same size, different keys), next[a] returns null, the value comparison passes, and the method incorrectly returns true. This can cause silent diffing errors (e.g., skipping updates when maps actually changed), leading to stale UI/state.

Severity: high
File: litho-core/src/main/java/com/facebook/litho/utils/MapDiffUtils.kt

Expected Behavior

The code should handle this case properly to avoid unexpected errors or degraded quality.