Show Numbers compactly when typeinfo is a Union with Nothing or Missing

base/rational.jl

@@ -95,7 +95,7 @@ end
 function show(io::IO, x::Rational)
     show(io, numerator(x))
 
-    if isone(denominator(x)) && get(io, :typeinfo, Any) <: Rational
+    if isone(denominator(x)) && nonnothing_nonmissing_typeinfo(io) <: Rational
         return
     end
 

base/ryu/Ryu.jl

@@ -112,7 +112,7 @@ end
 function Base.show(io::IO, x::T, forceuntyped::Bool=false, fromprint::Bool=false) where {T <: Base.IEEEFloat}
     compact = get(io, :compact, false)::Bool
     buf = Base.StringVector(neededdigits(T))
-    typed = !forceuntyped && !compact && get(io, :typeinfo, Any) != typeof(x)
+    typed = !forceuntyped && !compact && Base.nonnothing_nonmissing_typeinfo(io) != typeof(x)
     pos = writeshortest(buf, 1, x, false, false, true, -1,
         (x isa Float32 && !fromprint) ? UInt8('f') : UInt8('e'), false, UInt8('.'), typed, compact)
     write(io, resize!(buf, pos - 1))

base/show.jl

@@ -1231,8 +1231,9 @@ function show(io::IO, tn::Core.TypeName)
     print(io, ")")
 end
 
+nonnothing_nonmissing_typeinfo(io::IO) = nonmissingtype(nonnothingtype(get(io, :typeinfo, Any)))
+show(io::IO, b::Bool) = print(io, nonnothing_nonmissing_typeinfo(io) === Bool ? (b ? "1" : "0") : (b ? "true" : "false"))
 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))

test/show.jl

@@ -2170,6 +2170,20 @@ 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 #26847
+@test_repr "Union{Missing, Float32}[1.0]"
+
+# intersection of #45396 and #48822
+@test_repr "Union{Missing, Rational{Int64}}[missing, 1//2, 2]"
+
+# Don't go too far with #48822
+@test_repr "Union{String, Bool}[true]"
+
 # issue #30505
 @test repr(Union{Tuple{Char}, Tuple{Char, Char}}[('a','b')]) == "Union{Tuple{Char}, Tuple{Char, Char}}[('a', 'b')]"