Fix field type in unittest

Author: MilesCranmer

src/base.jl

@@ -52,9 +52,9 @@ julia> tree_mapreduce(t -> 1, (p, c...) -> p + max(c...), tree)  # compute depth
 5
 
 julia> tree_mapreduce(vcat, tree) do t
-    t.degree == 2 ? [t.op] : Int8[]
+    t.degree == 2 ? [t.op] : UInt8[]
 end  # Get list of binary operators used. (regular mapreduce also works)
-2-element Vector{Int8}:
+2-element Vector{UInt8}:
  1
  2
 

test/test_base.jl

@@ -114,8 +114,9 @@ end
     @test length(unique(map(objectid, copy_node(tree; preserve_sharing=true)))) == 24 - 3
     map(t -> (t.degree == 0 && t.constant) ? (t.val *= 2) : nothing, ctree)
     @test sum(t -> t.val, filter(t -> t.degree == 0 && t.constant, ctree)) == 11.6 * 2
-    @test typeof(map(t -> t.degree, ctree, Int8)) == Vector{Int8}
-    @test first(map(t -> t.degree, ctree, Int8)) == 2
+    local T = fieldtype(typeof(ctree), :degree)
+    @test typeof(map(t -> t.degree, ctree, T)) == Vector{T}
+    @test first(map(t -> t.degree, ctree, T)) == 2
 end
 
 @testset "in" begin