Add optional io choosing for `cowsay` and `cowthink`

src/Cowsay.jl

@@ -39,8 +39,8 @@ include("cows/vader.cow.jl")
 include("cows/www.cow.jl")
 
 """
-    cowsay(message::AbstractString; kwargs...)
-    cowthink(message::AbstractString; kwargs...)
+    cowsay([io,] message::AbstractString; kwargs...)
+    cowthink([io,] message::AbstractString; kwargs...)
 
 Print an ASCII picture of a cow saying/thinking `message`
 
@@ -79,18 +79,26 @@ julia> cowthink("Have I mooed today?")
 ```
 """
 function cowsay(message::AbstractString; cow=default, eyes="oo", tongue="  ")
-    println(cowsaid(message, cow=cow, eyes=eyes, tongue=tongue))
+    cowsay(stdout, message, cow=cow, eyes=eyes, tongue=tongue)
+end
+
+function cowsay(io::IO, message::AbstractString; cow=default, eyes="oo", tongue="  ")
+    println(io, cowsaid(message, cow=cow, eyes=eyes, tongue=tongue))
 end
 
 """
-    cowthink(message::AbstractString; kwargs...)
+    cowthink([io,] message::AbstractString; kwargs...)
 
 Print an ASCII picture of a cow thinking `message`
 
 See [`cowsay`](@ref)
 """
 function cowthink(message::AbstractString; cow=default, eyes="oo", tongue="  ")
-    println(cowthunk(message, cow=cow, eyes=eyes, tongue=tongue))
+    cowthink(stdout, message, cow=cow, eyes=eyes, tongue=tongue)
+end
+
+function cowthink(io::IO, message::AbstractString; cow=default, eyes="oo", tongue="  ")
+    println(io, cowthunk(message, cow=cow, eyes=eyes, tongue=tongue))
 end
 
 """

test/runtests.jl

@@ -18,4 +18,11 @@ DocMeta.setdocmeta!(Cowsay, :DocTestSetup, :(using Cowsay); recursive=true)
         # Multi-liner say balloon
         @test Cowsay.sayballoon("One line\nTwo line\nRed line\nBlue line") == " ___________\n/ One line  \\\n| Two line  |\n| Red line  |\n\\ Blue line /\n -----------\n"
     end
+    @testset "IO Funkiness" begin
+        # Cowsay with io redirection
+        @test_warn cowsaid("Moo") cowsay(stderr, "Moo")
+
+        # Cowthink with io redirection
+        @test_warn cowthunk("Moo") cowthink(stderr, "Moo")
+    end
 end