Make tests completely silent; remove set_gap warnings on Cbc

src/solution/methods/XavQiuWanThi2019/optimize.jl

@@ -3,13 +3,12 @@
 # Released under the modified BSD license. See COPYING.md for more details.
 
 function optimize!(model::JuMP.Model, method::XavQiuWanThi2019.Method)::Nothing
+    if !occursin("Gurobi", JuMP.solver_name(model))
+        method.two_phase_gap = false
+    end
     function set_gap(gap)
-        try
-            JuMP.set_optimizer_attribute(model, "MIPGap", gap)
-            @info @sprintf("MIP gap tolerance set to %f", gap)
-        catch
-            @warn "Could not change MIP gap tolerance"
-        end
+        JuMP.set_optimizer_attribute(model, "MIPGap", gap)
+        @info @sprintf("MIP gap tolerance set to %f", gap)
     end
     initial_time = time()
     large_gap = false
@@ -17,8 +16,6 @@ function optimize!(model::JuMP.Model, method::XavQiuWanThi2019.Method)::Nothing
     if has_transmission && method.two_phase_gap
         set_gap(1e-2)
         large_gap = true
-    else
-        set_gap(method.gap_limit)
     end
     while true
         time_elapsed = time() - initial_time

src/solution/methods/XavQiuWanThi2019/structs.jl

@@ -13,7 +13,7 @@ Lazy constraint solution method described in:
 module XavQiuWanThi2019
 import ..SolutionMethod
 """
-    struct Method
+    mutable struct Method
         time_limit::Float64
         gap_limit::Float64
         two_phase_gap::Bool
@@ -27,7 +27,7 @@ Fields
 - `time_limit`:
     the time limit over the entire optimization procedure.
 - `gap_limit`: 
-    the desired relative optimality gap.
+    the desired relative optimality gap. Only used when `two_phase_gap=true`.
 - `two_phase_gap`: 
     if true, solve the problem with large gap tolerance first, then reduce
     the gap tolerance when no further violated constraints are found.
@@ -39,7 +39,7 @@ Fields
     formulation per time period.
 
 """
-struct Method <: SolutionMethod
+mutable struct Method <: SolutionMethod
     time_limit::Float64
     gap_limit::Float64
     two_phase_gap::Bool