Use compact printing for Nullable

Print the wrapped value compactly, as inside other containers,
since the type information is redundant with the type parameter.
Also print the type with :multiline=>false.

base/nullable.jl

@@ -35,9 +35,11 @@ function show{T}(io::IO, x::Nullable{T})
  show(io, x.value)
  end
  else
- print(io, "Nullable{", T, "}(")
+ print(io, "Nullable{")
+ showcompact(io, eltype(x))
+ print(io, "}(")
  if !isnull(x)
- show(io, x.value)
+ showcompact(io, x.value)
  end
  print(io, ')')
  end

base/show.jl

@@ -1548,7 +1548,7 @@ function showcompact(io::IO, x)
  show(IOContext(io, :multiline => false), x)
  end
  else
- if get(io, :multiline, false)
+ if !get(io, :multiline, false)
  show(IOContext(io, :compact => true), x)
  else
  show(IOContext(IOContext(io, :compact => true),

test/nullable.jl

@@ -85,10 +85,10 @@ for (i, T) in enumerate(types)
  show(io1, x1)
  @test takebuf_string(io1) == @sprintf("Nullable{%s}()", T)
  show(io1, x2)
- show(io2, get(x2))
+ showcompact(io2, get(x2))
  @test takebuf_string(io1) == @sprintf("Nullable{%s}(%s)", T, takebuf_string(io2))
  show(io1, x3)
- show(io2, get(x3))
+ showcompact(io2, get(x3))
  @test takebuf_string(io1) == @sprintf("Nullable{%s}(%s)", T, takebuf_string(io2))
 
  a1 = [x2]
@@ -103,6 +103,10 @@ for (i, T) in enumerate(types)
  @sprintf("Nullable{%s}[%s]", string(T), takebuf_string(io2))
 end
 
+@enum NullableTestEnum a b
+show(io1, Nullable(a))
+@test takebuf_string(io1) == "Nullable{NullableTestEnum}(a)"
+
 # showcompact(io::IO, x::Nullable)
 io1 = IOBuffer()
 io2 = IOBuffer()