Add numerical correctness tests

Author: mcosovic

docs/src/release_notes.md

@@ -2,6 +2,25 @@
 
 ---
 
+## Version 0.2.5 - Unreleased
+
+#### Fixed
+
+- Fixed Gaussian min-sum frozen variable and edge message updates so frozen
+  outgoing quadratic messages remain unchanged until explicitly unfrozen.
+- Fixed inference-aware discrete factor updates so invalid initializing unary
+  updates are rejected before mutating the graph.
+
+#### Tests
+
+- Added numerical correctness coverage for Gaussian schedules, damping,
+  freeze/unfreeze message preservation, tree exactness and selected
+  step-by-step sweeps, root refreshes, warm-start updates, dynamic stale-state
+  rejection, residual partial updates, WLS agreement for correlated vector
+  models, and discrete brute-force references.
+
+---
+
 ## Version 0.2.4 - 2026-06-05
 
 #### Changed

src/inference/core.jl

@@ -1037,6 +1037,35 @@ function addFactor!(
     )
 end
 
+function validateDiscreteInferenceFactorUpdate(
+    graph::DiscreteFactorGraph,
+    factorRef::FactorRef;
+    table = nothing,
+    initialize::Union{Nothing, Bool} = nothing
+)
+    factorIdx = factorIndex(graph, factorRef)
+    current = graph.factors[factorIdx]
+    nextTable = table === nothing ? current.table : table
+    nextInitialize = initialize === nothing ? current.initialize : initialize
+    updated = DiscreteFactor(
+        current.id,
+        current.variables,
+        nextTable;
+        label = current.label,
+        initialize = nextInitialize
+    )
+
+    validateUpdatedFactorDimensions(current, updated)
+    validateFactor(updated, graph.variables, graph.referenceIndex)
+    validateUpdatedInitializingUnaryFactors(graph, factorIdx, updated)
+
+    if updated.initialize
+        initialMessageFromUnaryFactor(updated)
+    end
+
+    return nothing
+end
+
 function updateFactor!(
     graph::DiscreteFactorGraph,
     inference::DiscreteInference,

src/inference/discreteMinSum.jl

@@ -595,6 +595,12 @@ function updateFactor!(
     initialize::Union{Nothing, Bool} = nothing
 )
     assertDiscreteMinSumInferenceMatchesGraph(graph, inference)
+    validateDiscreteInferenceFactorUpdate(
+        graph,
+        factorRef;
+        table = table,
+        initialize = initialize
+    )
 
     updated = updateFactor!(
         graph,

src/inference/discreteSumProduct.jl

@@ -550,6 +550,12 @@ function updateFactor!(
     initialize::Union{Nothing, Bool} = nothing
 )
     assertDiscreteSumProductInferenceMatchesGraph(graph, inference)
+    validateDiscreteInferenceFactorUpdate(
+        graph,
+        factorRef;
+        table = table,
+        initialize = initialize
+    )
 
     updated = updateFactor!(
         graph,

src/inference/gaussianMinSum.jl

@@ -1037,14 +1037,14 @@ function variableToFactorMessage!(
 )
     edge = graph.edges[edgeId]
 
-    fill!(output.J, 0.0)
-    fill!(output.h, 0.0)
-    output.c = 0.0
-
     if inference.frozenEdges[edgeId] || inference.frozenVariables[edge.variableIndex]
         return output
     end
 
+    fill!(output.J, 0.0)
+    fill!(output.h, 0.0)
+    output.c = 0.0
+
     for incomingEdgeId in graph.variableEdges[edge.variableIndex]
         if incomingEdgeId == edgeId
             continue