Fix show(...) of invalid instances.

Project.toml

@@ -1,6 +1,6 @@
 name = "EnumX"
 uuid = "4e289a0a-7415-4d19-859d-a7e5c4648b56"
-version = "1.0.3"
+version = "1.0.4"
 
 [compat]
 julia = "1.6"

src/EnumX.jl

@@ -151,11 +151,16 @@ end
 function Base.show(io::IO, ::MIME"text/plain", x::E) where E <: Enum
     iob = IOBuffer()
     ix = Integer(x)
+    found = false
     for (k, v) in symbol_map(E)
         if v == ix
             print(iob, "$(nameof(parentmodule(E))).$(k) = ")
+            found = true
         end
     end
+    if !found
+        print(iob, "$(nameof(parentmodule(E))).#invalid# = ")
+    end
     show(iob, ix)
     write(io, seekstart(iob))
     return nothing

test/runtests.jl

@@ -266,6 +266,16 @@ end
 @test instances(FruitEmptyT.Typ) == ()
 
 
+# Showing invalid instances
+@enumx Invalid A
+let io = IOBuffer()
+    invalid = Base.bitcast(Invalid.T, Int32(1))
+    show(io, "text/plain", invalid)
+    str = String(take!(io))
+    @test str == "Invalid.#invalid# = 1"
+end
+
+
 # Documented type (module) and instances
 begin
     """