Show Bools as 0 and 1 when typeinfo is a Union of Bool with Nothing o…

…r Missing

base/show.jl

@@ -1141,10 +1141,13 @@ function show(io::IO, tn::Core.TypeName)
 end
 
 show(io::IO, ::Nothing) = print(io, "nothing")
-show(io::IO, b::Bool) = print(io, get(io, :typeinfo, Any) === Bool ? (b ? "1" : "0") : (b ? "true" : "false"))
 show(io::IO, n::Signed) = (write(io, string(n)); nothing)
 show(io::IO, n::Unsigned) = print(io, "0x", string(n, pad = sizeof(n)<<1, base = 16))
 print(io::IO, n::Unsigned) = print(io, string(n))
+function show(io::IO, b::Bool)
+    typeinfo = nonmissingtype(nonnothingtype(get(io, :typeinfo, Any)))
+    print(io, typeinfo === Bool ? (b ? "1" : "0") : (b ? "true" : "false"))
+end
 
 show(io::IO, p::Ptr) = print(io, typeof(p), " @0x$(string(UInt(p), base = 16, pad = Sys.WORD_SIZE>>2))")
 

test/show.jl

@@ -2118,6 +2118,11 @@ replstrcolor(x) = sprint((io, x) -> show(IOContext(io, :limit => true, :color =>
     @test_repr "Bool[1, 0]"
 end
 
+@testset "Unions with Bool (#39590)" begin
+    @test repr([missing, false]) == "Union{Missing, Bool}[missing, 0]"
+    @test_repr "Union{Bool, Nothing}[1, 0, nothing]"
+end
+
 # issue #30505
 @test repr(Union{Tuple{Char}, Tuple{Char, Char}}[('a','b')]) == "Union{Tuple{Char}, Tuple{Char, Char}}[('a', 'b')]"