Support anything that can save as PNG

Project.toml

@@ -23,6 +23,7 @@ ImageCore = "0.8.1"
 ImageInTerminal = "0.3, 0.4"
 ImageMagick = "0.7, 1"
 ImageTransformations = "0.8"
+Plots = "1.4.3"
 TestImages = "0.6, 1"
 julia = "1"
 
@@ -31,7 +32,8 @@ CSVFiles = "5d742f6a-9f54-50ce-8119-2520741973ca"
 DataFrames = "a93c6f00-e57d-5684-b7b6-d8193f3e46c0"
 ImageMagick = "6218d12a-5da1-5696-b52f-db25d2ecc6d1"
 ImageTransformations = "02fcd773-0e25-5acc-982a-7f6622650795"
+Plots = "91a5bcdd-55d7-5caf-9e0b-520d859cae80"
 TestImages = "5e47fb64-e119-507b-a336-dd2b206d9990"
 
 [targets]
-test = ["CSVFiles", "DataFrames", "ImageMagick", "ImageTransformations", "TestImages"]
+test = ["CSVFiles", "DataFrames", "ImageMagick", "ImageTransformations", "Plots", "TestImages"]

src/fileio.jl

@@ -64,6 +64,16 @@ function _convert(
     return join(strs,'\n')
 end
 
+# PNG  (Including images as arrays of colorants, and things like Plots.jl plots etc)
+function _convert(::Type{<:DataFormat{:PNG}}, data)::AbstractArray{<:Colorant}
+    mktempdir() do dir
+        filename = File{DataFormat{:PNG}}(joinpath(dir, "inconversion.png"))
+        savefile(filename, data)
+        load(filename)
+    end
+end
+_convert(::Type{<:DataFormat{:PNG}}, img::AbstractArray{<:Colorant}; kw...) = img
+
 # SHA256
 _convert(::Type{DataFormat{:SHA256}}, x; kw...) = bytes2hex(sha256(string(x)))
 function _convert(::Type{DataFormat{:SHA256}}, img::AbstractArray{<:Colorant}; kw...)

src/test_reference.jl

@@ -100,19 +100,20 @@ function test_reference(
     path = file.filename
     dir, filename = splitdir(path)
 
+    actual = _convert(F, raw_actual; kw...)
+
     # infer the default rendermode here
     # since `nothing` is always passed to this method from
     # test_reference(filename::AbstractString, raw_actual; kw...)
     if rendermode === nothing
-        rendermode = default_rendermode(F, raw_actual)
+        rendermode = default_rendermode(F, actual)
     end
 
-    actual = _convert(F, raw_actual; kw...)
     # preprocessing when reference file doesn't exists
     if !isfile(path)
         @info("Reference file for \"$filename\" does not exist. It will be created")
         # TODO: move encoding out from render
-        render(rendermode, raw_actual)
+        render(rendermode, actual)
 
         mkpath(dir)
         savefile(file, actual)
@@ -122,7 +123,7 @@ function test_reference(
     end
 
     # file exists
-    reference = loadfile(T, file)
+    reference = loadfile(typeof(actual), file)
 
     if equiv === nothing
         # generally, `reference` and `actual` are of the same type after preprocessing

test/runtests.jl

@@ -1,5 +1,6 @@
 using Test
 using ImageInTerminal, TestImages, ImageCore, ImageTransformations
+using Plots
 using Random
 
 if isinteractive()
@@ -120,6 +121,14 @@ end
     @test_throws Exception @test_reference "references/camera.png" camera # unequal size
 end
 
+@testset "Plots as PNG images" begin
+    # Test disabled on linux because: https://github.com/JuliaPlots/Plots.jl/issues/2127
+    if !Sys.islinux()
+        @test_reference "references/heatmap.png" heatmap([1 0; 0 1]) by=psnr_equality(15)
+        @test_reference "references/scatter.png" scatter([(0,0),(1,0),(0,1),(1,1)], ms=8)
+    end
+end
+
 using DataFrames, CSVFiles
 @testset "DataFrame as CSV" begin
     @test_reference "references/dataframe.csv" DataFrame(v1=[1,2,3], v2=["a","b","c"])