when showing union aliases, keep TypeVars last

ElOceanografo · May 4, 2021 · a25040d · a25040d
1 parent dfddd66
commit a25040d
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Showing 2 changed files with 22 additions and 9 deletions.
diff --git a/base/show.jl b/base/show.jl
@@ -749,16 +749,21 @@ end
 function show_unionaliases(io::IO, x::Union)
     properx = makeproper(io, x)
     aliases, applied = make_typealiases(properx)
+    isempty(aliases) && return false
     first = true
+    tvar = false
     for typ in uniontypes(x)
-        if !isa(typ, TypeVar) && rewrap_unionall(typ, properx) <: applied
+        if isa(typ, TypeVar)
+            tvar = true # sort bare TypeVars to the end
+            continue
+        elseif rewrap_unionall(typ, properx) <: applied
             continue
         end
         print(io, first ? "Union{" : ", ")
         first = false
         show(io, typ)
     end
-    if first && length(aliases) == 1
+    if first && !tvar && length(aliases) == 1
         alias = aliases[1]
         wheres = make_wheres(io, alias[2], x)
         show_typealias(io, alias[1], x, alias[2], wheres)
@@ -772,8 +777,17 @@ function show_unionaliases(io::IO, x::Union)
             show_typealias(io, alias[1], x, alias[2], wheres)
             show_wheres(io, wheres)
         end
+        if tvar
+            for typ in uniontypes(x)
+                if isa(typ, TypeVar)
+                    print(io, ", ")
+                    show(io, typ)
+                end
+            end
+        end
         print(io, "}")
     end
+    return true
 end
 
 function show(io::IO, ::MIME"text/plain", @nospecialize(x::Type))
@@ -813,12 +827,11 @@ function _show_type(io::IO, @nospecialize(x::Type))
         show_datatype(io, x)
         return
     elseif x isa Union
-        if get(io, :compact, true)
-            show_unionaliases(io, x)
-        else
-            print(io, "Union")
-            show_delim_array(io, uniontypes(x), '{', ',', '}', false)
+        if get(io, :compact, true) && show_unionaliases(io, x)
+            return
         end
+        print(io, "Union")
+        show_delim_array(io, uniontypes(x), '{', ',', '}', false)
         return
     end
 

diff --git a/test/show.jl b/test/show.jl
@@ -2088,9 +2088,9 @@ end
 @test string(M37012.BStruct{T, S} where {T<:Unsigned, S<:Signed}) == "$(curmod_prefix)M37012.B2{S, T} where {T<:Unsigned, S<:Signed}"
 @test string(M37012.BStruct{T, S} where {T<:Signed, S<:T}) == "$(curmod_prefix)M37012.B2{S, T} where {T<:Signed, S<:T}"
 @test string(Union{M37012.SimpleU, Nothing}) == "Union{Nothing, $(curmod_prefix)M37012.SimpleU}"
-@test string(Union{M37012.SimpleU, Nothing, T} where T) == "Union{Nothing, T, $(curmod_prefix)M37012.SimpleU} where T"
+@test string(Union{M37012.SimpleU, Nothing, T} where T) == "Union{Nothing, $(curmod_prefix)M37012.SimpleU, T} where T"
 @test string(Union{AbstractVector{T}, T} where T) == "Union{AbstractVector{T}, T} where T"
-@test string(Union{AbstractVector, T} where T) == "Union{T, AbstractVector{T} where T} where T"
+@test string(Union{AbstractVector, T} where T) == "Union{AbstractVector{T} where T, T} where T"
 
 @test sprint(show, :(./)) == ":((./))"
 @test sprint(show, :((.|).(.&, b))) == ":((.|).((.&), b))"