diff --git a/.travis.yml b/.travis.yml
index 43ba22b..2f9c38a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,6 +5,9 @@ os:
 julia:
     - 1.0
     - 1.1
+    - 1.2
+    - 1.3
+    - 1.4
 notifications:
     email: false
 sudo: false
diff --git a/Project.toml b/Project.toml
index c38bef5..2f824aa 100644
--- a/Project.toml
+++ b/Project.toml
@@ -10,16 +10,15 @@ MathOptInterface = "b8f27783-ece8-5eb3-8dc8-9495eed66fee"
 ParameterJuMP = "774612a8-9878-5177-865a-ca53ae2495f9"
 
 [compat]
-JuMP = "0.21"
-MathOptInterface = "0.9.1"
+JuMP = "0.21.3"
+MathOptInterface = "0.9.14"
 ParameterJuMP = "0.2"
 julia = "1"
 
 [extras]
 ECOS = "e2685f51-7e38-5353-a97d-a921fd2c8199"
 GLPK = "60bf3e95-4087-53dc-ae20-288a0d20c6a6"
-Ipopt = "b6b21f68-93f8-5de0-b562-5493be1d77c9"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test = ["GLPK", "Test", "ECOS", "Ipopt"]
+test = ["GLPK", "Test", "ECOS"]
diff --git a/src/StructJuMP.jl b/src/StructJuMP.jl
index 39cb173..7cb77c6 100644
--- a/src/StructJuMP.jl
+++ b/src/StructJuMP.jl
@@ -254,11 +254,17 @@ function JuMP.constraint_object(cref::StructuredConstraintRef, F::Type, S::Type)
 end
 
 # Objective
-function JuMP.set_objective(m::StructuredModel, sense::MOI.OptimizationSense,
-                            f::JuMP.AbstractJuMPScalar)
+
+function JuMP.set_objective_sense(m::StructuredModel, sense::MOI.OptimizationSense)
     m.objective_sense = sense
+end
+
+function JuMP.set_objective_function(m::StructuredModel, f::AbstractJuMPScalar)
     m.objective_function = f
 end
+
+JuMP.set_objective_function(m::StructuredModel, f::Real) = JuMP.set_objective_function(m, convert(AffExpr, f))
+
 JuMP.objective_sense(m::StructuredModel) = m.objective_sense
 JuMP.objective_function_type(model::StructuredModel) = typeof(model.objective_function)
 JuMP.objective_function(model::StructuredModel) = model.objective_function
diff --git a/test/examples_smoketest.jl b/test/examples_smoketest.jl
index b0147f2..7d15029 100644
--- a/test/examples_smoketest.jl
+++ b/test/examples_smoketest.jl
@@ -55,6 +55,14 @@ end
     # optimize!(firststage)
 end
 
+@testset "farmer" begin
+    include("../examples/farmer.jl")
+    # status, objval, soln = DLP(m, GLPK.Optimizer)
+    # @test status == :Optimal
+    # @test objval ≈ -108390
+    # @test soln ≈ [170, 80, 250]
+end
+
 #=
 @testset "stochpdegas" begin
     include("../examples/stochpdegas.jl")
diff --git a/test/farmer.jl b/test/farmer.jl
deleted file mode 100644
index ec589fb..0000000
--- a/test/farmer.jl
+++ /dev/null
@@ -1,11 +0,0 @@
-using Test
-
-using GLPK
-
-@testset "farmer" begin
-    include("../examples/farmer.jl")
-    status, objval, soln = DLP(m, GLPK.Optimizer)
-    @test status == :Optimal
-    @test objval ≈ -108390
-    @test soln ≈ [170, 80, 250]
-end
diff --git a/test/objective.jl b/test/objective.jl
new file mode 100644
index 0000000..fdac563
--- /dev/null
+++ b/test/objective.jl
@@ -0,0 +1,23 @@
+using Test
+using StructJuMP
+
+@testset "objective functions" begin
+    m = StructuredModel(num_scenarios = 2)
+    @variable(m, x >= 0)
+    @objective(m, Min, x*x)
+
+    sm = StructuredModel(parent = m, id = 1)
+    @variable(sm, y >= 0)
+    @objective(sm, Max, y)
+
+    sm = StructuredModel(parent = m, id = 2)
+    @variable(sm, y >= 0)
+    @objective(sm, Min, 0)
+
+    @test objective_sense(m) == MOI.MIN_SENSE
+    @test objective_sense(m.children[1]) == MOI.MAX_SENSE
+    @test objective_sense(m.children[2]) == MOI.MIN_SENSE
+    @test objective_function_type(m) == GenericQuadExpr{Float64,StructJuMP.StructuredVariableRef}
+    @test objective_function_type(m.children[1]) == StructJuMP.StructuredVariableRef
+    @test objective_function_type(m.children[2]) == GenericAffExpr{Float64,VariableRef}
+end
\ No newline at end of file
diff --git a/test/runtests.jl b/test/runtests.jl
index e30a0f6..892bc46 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -2,6 +2,6 @@ include("printhook.jl")
 
 include("benderstest.jl")
 
-# include("farmer.jl")
-
 include("examples_smoketest.jl")
+
+include("objective.jl")
\ No newline at end of file