Also test the generic code path

Author: timholy

Project.toml

@@ -31,8 +31,9 @@ ImageIO = "82e4d734-157c-48bb-816b-45c225c6df19"
 ImageMagick = "6218d12a-5da1-5696-b52f-db25d2ecc6d1"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 ReferenceTests = "324d217c-45ce-50fc-942e-d289b448e8cf"
+Tau = "c544e3c2-d3e5-5802-ac44-44683f340e4a"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 TestImages = "5e47fb64-e119-507b-a336-dd2b206d9990"
 
 [targets]
-test = ["EndpointRanges", "ImageIO", "ImageMagick", "LinearAlgebra", "ReferenceTests", "Test", "TestImages"]
+test = ["EndpointRanges", "ImageIO", "ImageMagick", "LinearAlgebra", "ReferenceTests", "Tau", "Test", "TestImages"]

test/warp.jl

@@ -1,5 +1,6 @@
 using CoordinateTransformations, Rotations, TestImages, ImageCore, StaticArrays, OffsetArrays, Interpolations, LinearAlgebra
 using EndpointRanges
+using Tau
 using Test, ReferenceTests
 
 include("twoints.jl")
@@ -470,6 +471,11 @@ NaN  NaN      NaN      NaN      NaN      NaN      NaN
             @test axes(imrotate(img_camera, pi/2)) == axes(img_camera)
             @test imrotate(imrotate(imrotate(imrotate(img_camera, pi/2), pi/2), pi/2), pi/2) ≈ img_camera
             @test imrotate(imrotate(img_camera, pi), pi) == img_camera
+            # Also check a "generic" irrational (one that happens to be quite special)
+            ## First, check that this hits the generic code path (if we change that, pick a different irrational)
+            @test ImageTransformations._mod2pi(τ) isa Float64
+            ## Now check that it gives the expected result
+            @test imrotate(img_camera, τ) ≈ img_camera
         end
     end
 end