Merge pull request #390 from JuliaOpt/bl/cachingoptOT

Add type parameter for CachingOptimizer

Author: blegat

perf/cachingoptimizer.jl

@@ -1,4 +1,6 @@
-# See https://github.com/JuliaOpt/MathOptInterface.jl/issues/321 and https://github.com/JuliaOpt/MathOptInterface.jl/pull/323
+# See https://github.com/JuliaOpt/MathOptInterface.jl/issues/321,
+#     https://github.com/JuliaOpt/MathOptInterface.jl/pull/323 and
+#     https://github.com/JuliaOpt/MathOptInterface.jl/pull/390
 
 using BenchmarkTools
 using MathOptInterface
@@ -10,7 +12,7 @@ optimizer = MOIU.MockOptimizer(Model{Float64}())
 caching_optimizer = MOIU.CachingOptimizer(Model{Float64}(), optimizer)
 MOIU.resetoptimizer!(caching_optimizer) # detach optimizer
 v = MOI.addvariables!(caching_optimizer, 2)
-cf = MOI.ScalarAffineFunction(v, [0.0, 0.0], 0.0)
+cf = MOI.ScalarAffineFunction(MOI.ScalarAffineTerm.([0.0, 0.0], v), 0.0)
 c = MOI.addconstraint!(caching_optimizer, cf, MOI.Interval(-Inf, 1.0))
 @btime MOI.modifyconstraint!($caching_optimizer, $c, $(MOI.Interval(0.0, 2.0)))
 MOIU.attachoptimizer!(caching_optimizer)

src/Utilities/cachingoptimizer.jl

@@ -22,9 +22,9 @@ A `CachingOptimizer` has two modes of operation (`CachingOptimizerMode`):
 - `Manual`: The only methods that change the state of the `CachingOptimizer` are [`resetoptimizer!`](@ref), [`dropoptimizer!`](@ref), and [`attachoptimizer!`](@ref). Attempting to perform an operation in the incorrect state results in an error.
 - `Automatic`: The `CachingOptimizer` changes its state when necessary. For example, `optimize!` will automatically call `attachoptimizer!` (an optimizer must have been previously set). Attempting to add a constraint or perform a modification not supported by the optimizer results in a drop to `EmptyOptimizer` mode.
 """
-mutable struct CachingOptimizer{MT<:MOI.ModelLike} <: MOI.AbstractOptimizer
-    model_cache::MT
-    optimizer::Union{Nothing,MOI.AbstractOptimizer}
+mutable struct CachingOptimizer{OptimizerType, ModelType<:MOI.ModelLike} <: MOI.AbstractOptimizer
+    optimizer::Union{Nothing, OptimizerType}
+    model_cache::ModelType
     state::CachingOptimizerState
     mode::CachingOptimizerMode
     model_to_optimizer_map::IndexMap
@@ -34,19 +34,25 @@ mutable struct CachingOptimizer{MT<:MOI.ModelLike} <: MOI.AbstractOptimizer
     # optimizer indices.
 end
 
-CachingOptimizer(model_cache::MOI.ModelLike, mode::CachingOptimizerMode) = CachingOptimizer(model_cache, nothing, NoOptimizer, mode, IndexMap(), IndexMap())
+function CachingOptimizer(model_cache::MOI.ModelLike, mode::CachingOptimizerMode)
+    CachingOptimizer{MOI.AbstractOptimizer, typeof(model_cache)}(nothing, model_cache, NoOptimizer, mode, IndexMap(), IndexMap())
+end
 
 """
     CachingOptimizer(model_cache::MOI.ModelLike, optimizer::AbstractOptimizer)
 
 Creates an `CachingOptimizer` in `Automatic` mode, with the optimizer `optimizer`.
 The model_cache manager returned behaves like an `AbstractOptimizer` as long as no
-`CachingOptimizer`-specific functions (e.g. `dropoptimizer!`) are called on it.
+`CachingOptimizer`-specific functions (e.g. `resetoptimizer!`) are called on it.
+The type of the optimizer returned is `CachingOptimizer{typeof(optimizer),
+typeof(model_cache)}` so it does not support the function
+`resetoptimizer!(::CachingOptimizer, new_optimizer)` if the type of
+`new_optimizer` is different from the type of `optimizer`.
 """
 function CachingOptimizer(model_cache::MOI.ModelLike, optimizer::MOI.AbstractOptimizer)
     @assert MOI.isempty(model_cache)
     @assert MOI.isempty(optimizer)
-    CachingOptimizer(model_cache, optimizer, AttachedOptimizer, Automatic, IndexMap(), IndexMap())
+    CachingOptimizer{typeof(optimizer), typeof(model_cache)}(optimizer, model_cache, AttachedOptimizer, Automatic, IndexMap(), IndexMap())
 end
 
 ## Methods for managing the state of CachingOptimizer.

test/cachingoptimizer.jl

@@ -167,6 +167,7 @@ end
         s = MOIU.MockOptimizer(ModelForMock{Float64}())
         model = ModelForCachingOptimizer{Float64}()
         m = MOIU.CachingOptimizer(model, s)
+        @test m isa MOIU.CachingOptimizer{typeof(s), typeof(model)}
         @test MOI.isempty(m)
         @test MOIU.state(m) == MOIU.AttachedOptimizer
         @test MOIU.mode(m) == MOIU.Automatic