[Bridges] revert changes included in 1919 by mistake (#1928)

Author: odow

Diff for: src/Bridges/Constraint/bridges/semi_to_binary.jl

@@ -75,19 +75,6 @@ function bridge_constraint(
     f::MOI.VariableIndex,
     s::S,
 ) where {T<:Real,S<:Union{MOI.Semicontinuous{T},MOI.Semiinteger{T}}}
-    F = MOI.VariableIndex
-    if MOI.is_valid(model, MOI.ConstraintIndex{F,MOI.GreaterThan{T}}(f.value))
-        throw(MOI.LowerBoundAlreadySet{MOI.GreaterThan{T},S}(f))
-    end
-    if MOI.is_valid(model, MOI.ConstraintIndex{F,MOI.LessThan{T}}(f.value))
-        throw(MOI.UpperBoundAlreadySet{MOI.LessThan{T},S}(f))
-    end
-    if MOI.is_valid(model, MOI.ConstraintIndex{F,MOI.EqualTo{T}}(f.value))
-        throw(MOI.LowerBoundAlreadySet{MOI.EqualTo{T},S}(f))
-    end
-    if MOI.is_valid(model, MOI.ConstraintIndex{F,MOI.Interval{T}}(f.value))
-        throw(MOI.LowerBoundAlreadySet{MOI.Interval{T},S}(f))
-    end
     binary, binary_con = MOI.add_constrained_variable(model, MOI.ZeroOne())
     # var - LB * bin >= 0
     lb = MOI.Utilities.operate(*, T, -s.lower, binary)
@@ -340,25 +327,3 @@ function MOI.get(
 ) where {T,S}
     return [b.lower_bound_index]
 end
-
-MOI.Bridges.needs_final_touch(b::SemiToBinaryBridge) = true
-
-function MOI.Bridges.final_touch(
-    b::SemiToBinaryBridge{T,S},
-    model::MOI.ModelLike,
-) where {T,S}
-    F, f = MOI.VariableIndex, b.variable
-    if MOI.is_valid(model, MOI.ConstraintIndex{F,MOI.GreaterThan{T}}(f.value))
-        throw(MOI.LowerBoundAlreadySet{S,MOI.GreaterThan{T}}(f))
-    end
-    if MOI.is_valid(model, MOI.ConstraintIndex{F,MOI.LessThan{T}}(f.value))
-        throw(MOI.UpperBoundAlreadySet{S,MOI.LessThan{T}}(f))
-    end
-    if MOI.is_valid(model, MOI.ConstraintIndex{F,MOI.EqualTo{T}}(f.value))
-        throw(MOI.LowerBoundAlreadySet{S,MOI.EqualTo{T}}(f))
-    end
-    if MOI.is_valid(model, MOI.ConstraintIndex{F,MOI.Interval{T}}(f.value))
-        throw(MOI.LowerBoundAlreadySet{S,MOI.Interval{T}}(f))
-    end
-    return
-end

Diff for: test/Bridges/Constraint/semi_to_binary.jl

@@ -242,65 +242,25 @@ function test_SemiToBinary()
 end
 
 """
-Test an error is thrown if a bound is added _after_ the semi-xxx constraint.
+    test_lower_bound_already_set()
 
-Note that this means the error is thrown from `Bridges.final_touch`.
+The second call to `add_constraint` is broken because it should throw:
+```julia
+MOI.LowerBoundAlreadySet{
+    MOI.Semicontinuous{Float64},
+    MOI.GreaterThan{Float64},
+}
+```
+See MathOptInterface issue #1431.
 """
-function test_bounds_already_set_final_touch()
-    for set in [MOI.GreaterThan(0.0), MOI.EqualTo(1.4), MOI.Interval(0.0, 2.0)]
-        model = MOI.Utilities.Model{Float64}()
-        bridged = MOI.Bridges.Constraint.SemiToBinary{Float64}(model)
-        x = MOI.add_variable(bridged)
-        semi_set = MOI.Semicontinuous(1.0, 2.0)
-        MOI.add_constraint(bridged, x, semi_set)
-        MOI.add_constraint(bridged, x, set)
-        @test_throws(
-            MOI.LowerBoundAlreadySet{typeof(semi_set),typeof(set)}(x),
-            MOI.Bridges.final_touch(bridged),
-        )
-    end
-    for set in [MOI.LessThan(2.0)]
-        model = MOI.Utilities.Model{Float64}()
-        bridged = MOI.Bridges.Constraint.SemiToBinary{Float64}(model)
-        x = MOI.add_variable(bridged)
-        semi_set = MOI.Semicontinuous(1.0, 2.0)
-        MOI.add_constraint(bridged, x, semi_set)
-        MOI.add_constraint(bridged, x, set)
-        @test_throws(
-            MOI.UpperBoundAlreadySet{typeof(semi_set),typeof(set)}(x),
-            MOI.Bridges.final_touch(bridged),
-        )
-    end
-    return
-end
-
-"""
-Test an error is thrown if a bound exists prior to adding the semi-xxx
-constraint.
-"""
-function test_bounds_already_set()
-    for set in [MOI.GreaterThan(0.0), MOI.EqualTo(1.4), MOI.Interval(0.0, 2.0)]
-        model = MOI.Utilities.Model{Float64}()
-        bridged = MOI.Bridges.Constraint.SemiToBinary{Float64}(model)
-        x = MOI.add_variable(bridged)
-        semi_set = MOI.Semicontinuous(1.0, 2.0)
-        MOI.add_constraint(bridged, x, set)
-        @test_throws(
-            MOI.LowerBoundAlreadySet{typeof(set),typeof(semi_set)}(x),
-            MOI.add_constraint(bridged, x, semi_set),
-        )
-    end
-    for set in [MOI.LessThan(2.0)]
-        model = MOI.Utilities.Model{Float64}()
-        bridged = MOI.Bridges.Constraint.SemiToBinary{Float64}(model)
-        x = MOI.add_variable(bridged)
-        semi_set = MOI.Semicontinuous(1.0, 2.0)
-        MOI.add_constraint(bridged, x, set)
-        @test_throws(
-            MOI.UpperBoundAlreadySet{typeof(set),typeof(semi_set)}(x),
-            MOI.add_constraint(bridged, x, semi_set)
-        )
-    end
+function test_lower_bound_already_set()
+    model = MOI.Utilities.Model{Float64}()
+    bridged = MOI.Bridges.Constraint.SemiToBinary{Float64}(model)
+    x = MOI.add_variable(bridged)
+    MOI.add_constraint(bridged, x, MOI.Semicontinuous(1.0, 2.0))
+    @test_broken(
+        MOI.add_constraint(bridged, x, MOI.GreaterThan(0.0)) === nothing,
+    )
     return
 end