Do not set variable name when unsupported by solver in _moi_add_constrained_variables (#3995)

Author: guimarqu

src/variables.jl

@@ -2223,7 +2223,7 @@ function _moi_add_variable(
     end
     if !isempty(name)
         if MOI.supports(moi_backend, MOI.VariableName(), MOI.VariableIndex)
-            set_name(x, name)
+            MOI.set(moi_backend, MOI.VariableName(), index, name)
         end
     end
     return x
@@ -2346,7 +2346,8 @@ function _moi_add_constrained_variable(
 ) where {T}
     var_index, con_index = MOI.add_constrained_variable(moi_backend, set)
     _moi_constrain_variable(moi_backend, var_index, scalar_variable.info, T)
-    if !isempty(name)
+    supports = MOI.supports(moi_backend, MOI.VariableName(), MOI.VariableIndex)
+    if !isempty(name) && supports
         MOI.set(moi_backend, MOI.VariableName(), var_index, name)
     end
     return var_index, con_index
@@ -2433,7 +2434,8 @@ function _moi_add_constrained_variables(
     for (index, variable) in zip(var_indices, scalar_variables)
         _moi_constrain_variable(moi_backend, index, variable.info, T)
     end
-    if names !== nothing
+    supports = MOI.supports(moi_backend, MOI.VariableName(), MOI.VariableIndex)
+    if names !== nothing && supports
         for (var_index, name) in zip(var_indices, names)
             if !isempty(name)
                 MOI.set(moi_backend, MOI.VariableName(), var_index, name)
@@ -2454,7 +2456,8 @@ function _moi_add_constrained_variables(
     for (index, variable) in zip(var_indices, scalar_variables)
         _moi_constrain_variable(moi_backend, index, variable.info, T)
     end
-    if names !== nothing
+    supports = MOI.supports(moi_backend, MOI.VariableName(), MOI.VariableIndex)
+    if names !== nothing && supports
         for (var_index, name) in zip(var_indices, names)
             if !isempty(name)
                 MOI.set(moi_backend, MOI.VariableName(), var_index, name)

test/test_variable.jl

@@ -1778,4 +1778,28 @@ function test_variable_in_set_HermitianPSDCone()
     return
 end
 
+function test_direct_model_variable_in_set_Parameter()
+    inner = MOIU.MockOptimizer(MOIU.Model{Float64}(); supports_names = false)
+    model = direct_model(inner)
+    @variable(model, x in Parameter(0.0))
+    @test is_parameter(x)
+    return
+end
+
+function test_direct_model_variable_in_set_SOS1()
+    inner = MOIU.MockOptimizer(MOIU.Model{Float64}(); supports_names = false)
+    model = direct_model(inner)
+    @variable(model, x[1:2] in SOS1([1.0, 2.0]))
+    @test num_variables(model) == 2
+    return
+end
+
+function test_direct_model_variable_in_set_Reals()
+    inner = MOIU.MockOptimizer(MOIU.Model{Float64}(); supports_names = false)
+    model = direct_model(inner)
+    @variable(model, x[1:2] in MOI.Reals(2))
+    @test num_variables(model) == 2
+    return
+end
+
 end  # module TestVariable