Fix fix fix tests, reduce code duplication

Author: penelopeysm

ext/SliceSamplingTuringExt.jl

@@ -22,30 +22,19 @@ Turing.Inference.isgibbscomponent(::SliceSampling.Slice) = true
 Turing.Inference.isgibbscomponent(::SliceSampling.SliceSteppingOut) = true
 Turing.Inference.isgibbscomponent(::SliceSampling.SliceDoublingOut) = true
 
+const SliceSamplingStates = Union{
+    SliceSampling.UnivariateSliceState,
+    SliceSampling.GibbsState,
+    SliceSampling.HitAndRunState,
+    SliceSampling.LatentSliceState,
+    SliceSampling.GibbsPolarSliceState,
+}
 function Turing.Inference.getparams(
-    ::Turing.DynamicPPL.Model, sample::SliceSampling.UnivariateSliceState
+    ::Turing.DynamicPPL.Model, sample::SliceSamplingStates
 )
     return sample.transition.params
 end
 
-function Turing.Inference.getparams(
-    ::Turing.DynamicPPL.Model, state::SliceSampling.GibbsState
-)
-    return state.transition.params
-end
-
-function Turing.Inference.getparams(
-    ::Turing.DynamicPPL.Model, state::SliceSampling.HitAndRunState
-)
-    return state.transition.params
-end
-
-function Turing.Inference.getparams(
-    ::Turing.DynamicPPL.Model, state::SliceSampling.LatentSliceState
-)
-    return state.transition.params
-end
-
 function Turing.Inference.getlogp_external(
     ::Turing.DynamicPPL.Model, t::SliceSampling.Transition, state
 )