adding ObjectiveLimit attribute

docs/src/manual/models.md

@@ -100,3 +100,4 @@ The following attributes are available:
  * [`SolverVersion`](@ref)
  * [`SolveTimeSec`](@ref)
  * [`TimeLimitSec`](@ref)
+ * [`ObjectiveLimit`](@ref)

docs/src/reference/models.md

@@ -77,6 +77,7 @@ SolverName
 SolverVersion
 Silent
 TimeLimitSec
+ObjectiveLimit
 RawOptimizerAttribute
 NumberOfThreads
 RawSolver

docs/src/tutorials/implementing.md

@@ -333,6 +333,7 @@ method for each attribute.
 | [`Name`](@ref)         | Yes           | Yes           | Yes                |
 | [`Silent`](@ref)       | Yes           | Yes           | Yes                |
 | [`TimeLimitSec`](@ref) | Yes           | Yes           | Yes                |
+| [`ObjectiveLimit`](@ref) | Yes         | Yes           | Yes                |
 | [`RawOptimizerAttribute`](@ref) | Yes  | Yes           | Yes                |
 | [`NumberOfThreads`](@ref) | Yes        | Yes           | Yes                |
 | [`AbsoluteGapTolerance`](@ref) | Yes   | Yes           | Yes                |

src/Test/test_attribute.jl

@@ -190,6 +190,32 @@ function setup_test(
     return
 end
 
+function test_attribute_ObjectiveLimit(model::MOI.AbstractOptimizer, ::Config)
+    @requires MOI.supports(model, MOI.ObjectiveLimit())
+    # Get the current value to restore it at the end of the test
+    value = MOI.get(model, MOI.ObjectiveLimit())
+    MOI.set(model, MOI.ObjectiveLimit(), 0.0)
+    @test MOI.get(model, MOI.ObjectiveLimit()) == 0.0
+    MOI.set(model, MOI.ObjectiveLimit(), nothing)
+    @test MOI.get(model, MOI.ObjectiveLimit()) === nothing
+    MOI.set(model, MOI.ObjectiveLimit(), 1.0)
+    @test MOI.get(model, MOI.ObjectiveLimit()) == 1.0
+    MOI.set(model, MOI.ObjectiveLimit(), value)
+    @test value == MOI.get(model, MOI.ObjectiveLimit()) # Equality should hold
+    _test_attribute_value_type(model, MOI.ObjectiveLimit())
+    return
+end
+test_attribute_ObjectiveLimit(::MOI.ModelLike, ::Config) = nothing
+
+function setup_test(
+    ::typeof(test_attribute_ObjectiveLimit),
+    model::MOIU.MockOptimizer,
+    ::Config,
+)
+    MOI.set(model, MOI.ObjectiveLimit(), nothing)
+    return
+end
+
 """
     test_attribute_AbsoluteGapTolerance(model::MOI.AbstractOptimizer, config::Config)
 

src/attributes.jl

@@ -850,6 +850,23 @@ struct TimeLimitSec <: AbstractOptimizerAttribute end
 
 attribute_value_type(::TimeLimitSec) = Union{Nothing,Float64}
 
+"""
+    ObjectiveLimit()
+
+An optimizer attribute for setting a limit on the objective value.
+
+The provided limit must be a `Union{Real,Nothing}`.
+
+When `set` to `nothing`, the limit reverts to the solver's default.
+
+The default value is `nothing`.
+
+The solver may stop when the [`ObjectiveValue`](@ref) is better (lower for
+minimization, higher for maximization) than the `ObjectiveLimit`. If stopped,
+the [`TerminationStatus`](@ref) should be `OBJECTIVE_LIMIT`.
+"""
+struct ObjectiveLimit <: AbstractOptimizerAttribute end
+
 """
     RawOptimizerAttribute(name::String)
 

test/Utilities/cachingoptimizer.jl

@@ -190,6 +190,7 @@ function test_default_attributes()
         MOI.SolverName(),
         MOI.Silent(),
         MOI.TimeLimitSec(),
+        MOI.ObjectiveLimit(),
         MOI.NumberOfThreads(),
         MOI.ResultCount(),
     )
@@ -209,22 +210,28 @@ function test_copyable_solver_attributes()
     cached = MOIU.CachingOptimizer(cache, MOIU.MANUAL)
     MOI.set(cached, MOI.Silent(), true)
     MOI.set(cached, MOI.TimeLimitSec(), 0.0)
+    MOI.set(cached, MOI.ObjectiveLimit(), 42.0)
     MOI.set(cached, MOI.NumberOfThreads(), 1)
     mock = MOIU.MockOptimizer(MOIU.UniversalFallback(MOIU.Model{Float64}()))
     MOIU.reset_optimizer(cached, mock)
     @test MOI.get(mock, MOI.Silent())
     @test MOI.get(cached, MOI.Silent())
     @test MOI.get(mock, MOI.TimeLimitSec()) == 0.0
     @test MOI.get(cached, MOI.TimeLimitSec()) == 0.0
+    @test MOI.get(mock, MOI.ObjectiveLimit()) == 42.0
+    @test MOI.get(cached, MOI.ObjectiveLimit()) == 42.0
     @test MOI.get(mock, MOI.NumberOfThreads()) == 1
     @test MOI.get(cached, MOI.NumberOfThreads()) == 1
     MOI.set(cached, MOI.Silent(), false)
     MOI.set(cached, MOI.TimeLimitSec(), 1.0)
+    MOI.set(cached, MOI.ObjectiveLimit(), 1.0)
     MOI.set(cached, MOI.NumberOfThreads(), 2)
     @test !MOI.get(mock, MOI.Silent())
     @test !MOI.get(cached, MOI.Silent())
     @test MOI.get(mock, MOI.TimeLimitSec()) ≈ 1.0
+    @test MOI.get(mock, MOI.ObjectiveLimit()) ≈ 1.0
     @test MOI.get(cached, MOI.TimeLimitSec()) ≈ 1.0
+    @test MOI.get(cached, MOI.ObjectiveLimit()) ≈ 1.0
     @test MOI.get(mock, MOI.NumberOfThreads()) == 2
     @test MOI.get(cached, MOI.NumberOfThreads()) == 2
     mock = MOIU.MockOptimizer(MOIU.UniversalFallback(MOIU.Model{Float64}()))
@@ -233,6 +240,8 @@ function test_copyable_solver_attributes()
     @test !MOI.get(cached, MOI.Silent())
     @test MOI.get(mock, MOI.TimeLimitSec()) ≈ 1.0
     @test MOI.get(cached, MOI.TimeLimitSec()) ≈ 1.0
+    @test MOI.get(mock, MOI.ObjectiveLimit()) ≈ 1.0
+    @test MOI.get(cached, MOI.ObjectiveLimit()) ≈ 1.0
     @test MOI.get(mock, MOI.NumberOfThreads()) == 2
     @test MOI.get(cached, MOI.NumberOfThreads()) == 2
     MOI.set(cached, MOI.Silent(), true)

test/Utilities/universalfallback.jl

@@ -382,6 +382,7 @@ function test_missing_attribute()
     model = MOI.Utilities.UniversalFallback(MOI.Utilities.Model{Float64}())
     @test MOI.get(model, MOI.Test.UnknownModelAttribute()) === nothing
     @test MOI.get(model, MOI.TimeLimitSec()) === nothing
+    @test MOI.get(model, MOI.ObjectiveLimit()) === nothing
     return
 end