[Bridges] add support for querying ConstraintConflictStatus

Author: odow

src/Bridges/bridge_optimizer.jl

@@ -1744,6 +1744,27 @@ function MOI.set(
     return throw(MOI.SettingVariableIndexNotAllowed())
 end
 
+function MOI.get(
+    model::AbstractBridgeOptimizer,
+    attr::MOI.ConstraintConflictStatus,
+    bridge::AbstractBridge,
+)
+    ret = MOI.NOT_IN_CONFLICT
+    for (F, S) in MOI.Bridges.added_constraint_types(typeof(bridge))
+        for ci in MOI.get(bridge, MOI.ListOfConstraintIndices{F,S}())
+            status = MOI.get(model, attr, ci)
+            if status == MOI.IN_CONFLICT
+                return status
+            elseif status == MOI.MAYBE_IN_CONFLICT
+                ret = status
+            # elseif status == MOI.NOT_IN_CONFLICT
+            # Nothing to do here.
+            end
+        end
+    end
+    return ret
+end
+
 ## Getting and Setting names
 function MOI.get(
     b::AbstractBridgeOptimizer,

test/Bridges/lazy_bridge_optimizer.jl

@@ -2288,6 +2288,46 @@ function test_wrong_coefficient_2()
     return
 end
 
+MOI.Utilities.@model(
+    Model2838,
+    (),
+    (MOI.GreaterThan,),
+    (),
+    (),
+    (),
+    (MOI.ScalarAffineFunction,),
+    (),
+    ()
+)
+
+function test_issue_2838()
+    inner = MOI.Utilities.MockOptimizer(Model2838{Float64}())
+    model = MOI.Bridges.full_bridge_optimizer(inner, Float64)
+    x = MOI.add_variables(model, 2)
+    f = MOI.Utilities.operate(vcat, Float64, (1.0 * x)...)
+    c = MOI.add_constraint(model, f, MOI.Nonnegatives(2))
+    F, S = MOI.ScalarAffineFunction{Float64}, MOI.GreaterThan{Float64}
+    ci = MOI.get(inner, MOI.ListOfConstraintIndices{F,S}())
+    function cmp(a, b)
+        if a == MOI.IN_CONFLICT || b == MOI.IN_CONFLICT
+            return MOI.IN_CONFLICT
+        elseif a == MOI.MAYBE_IN_CONFLICT || b == MOI.MAYBE_IN_CONFLICT
+            return MOI.MAYBE_IN_CONFLICT
+        else
+            return MOI.NOT_IN_CONFLICT
+        end
+    end
+    list = (MOI.NOT_IN_CONFLICT, MOI.IN_CONFLICT, MOI.MAYBE_IN_CONFLICT)
+    for a in list, b in list
+        MOI.set(inner, MOI.ConflictCount(), 1)
+        MOI.set(inner, MOI.ConstraintConflictStatus(), ci[1], a)
+        MOI.set(inner, MOI.ConstraintConflictStatus(), ci[2], b)
+        MOI.compute_conflict!(model)
+        @test MOI.get(model, MOI.ConstraintConflictStatus(), c) == cmp(a, b)
+    end
+    return
+end
+
 end  # module
 
 TestBridgesLazyBridgeOptimizer.runtests()