Remove any files stored in test/images (#195)

* Remove any files stored in test/images

* Removed file check and created it as a unit test

* Unit test for test/images dir to check for additional files

* Added formatting

test/unit.jl

@@ -1,4 +1,19 @@
 @testset "unit tests" begin
+
+    @testset "tmpdir" begin
+
+        #=
+        Leftover files from failed tests or errors can cause testing errors.
+        Therefore, we remove any files in the `images` directory not pertinent to testing before executing a test.
+        =#
+
+        EXCLUDE_FILES = [".keep"]
+        for f in readdir("images")
+            !(f in EXCLUDE_FILES) && rm("images/$f")
+        end
+        @test length(readdir("images")) == length(EXCLUDE_FILES)
+    end
+
     @testset "projection" begin
         x0 = Line(Point(0, 10), O)
         p = Point(10, 20)