A lot of progress on the propagator

julia/test/propagator.jl

@@ -0,0 +1,33 @@
+@testset "Propagator" begin
+
+  # Set up
+  start = oe_to_xyz([ (μs["Earth"]*(rand(3600*1.5:0.01:3600*4)/(2π))^2)^(1/3),
+                       rand(0.01:0.01:0.5),
+                       rand(0.01:0.01:0.45π),
+                       0.,
+                       0.,
+                       1. ], μs["Earth"])
+  stepsize = rand(100.0:0.01:500.0)
+
+  # Test that Laguerre-Conway is the default propagator
+  propped = prop_one([0., 0., 0.], start, 0., 0, 0., 1000., 0.1, μs["Earth"], stepsize)
+  @test laguerre_conway(start, μs["Earth"], stepsize) ≈ propped[1]
+
+  # Test that Laguerre-Conway is the default propagator for spacecrafts
+  craft = sc("no_thrust")
+  state, craft = prop_one([0., 0., 0.], start, craft, μs["Earth"], stepsize)
+  @test laguerre_conway(start, μs["Earth"], stepsize) ≈ state
+  @test craft.mass == 1000.
+
+  # Test that mass is reduced properly
+  craft = sc("test")
+  start_mass = craft.mass
+  state, craft = prop_one([1., 1., 1.]/√(3), start, craft, μs["Earth"], stepsize)
+  @test craft.mass == start_mass - craft.mass_flow_rate*stepsize
+  
+  # Test that a bad ΔV throws an error
+  craft = sc("test")
+  start_mass = craft.mass
+  @test_throws ErrorException prop_one([1., 1., -1.], start, craft, μs["Earth"], stepsize)
+
+end