use demo for tests

Project.toml

@@ -23,7 +23,8 @@ Preferences = "1"
 julia = "1.6"
 
 [extras]
+Printf = "de0858da-6303-5e67-8744-51eddeeeb8d7"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test = ["Test"]
+test = ["Printf","Test"]

demo/demo.jl

@@ -63,6 +63,14 @@ ImGuiGLFWBackend.init(glfw_ctx)
 opengl_ctx = ImGuiOpenGLBackend.create_context(glsl_version)
 ImGuiOpenGLBackend.init(opengl_ctx)
 
+window_should_close = false
+if haskey(ENV, "AUTO_CLOSE_DEMO")
+    tsecs = parse(Int, ENV["AUTO_CLOSE_DEMO"])
+    Timer(tsecs) do t
+        window_should_close = true
+    end
+end
+
 try
     show_demo_window = true
     show_another_window = false
@@ -120,6 +128,8 @@ try
 
         glfwMakeContextCurrent(window)
         glfwSwapBuffers(window)
+
+        window_should_close && break
     end
 catch e
     @error "Error in renderloop!" exception=e

test/runtests.jl

@@ -2,5 +2,7 @@ using CImGui
 using Test
 
 @testset "CImGui.jl" begin
-    # Write your own tests here.
+    withenv("AUTO_CLOSE_DEMO" => 10) do
+        include(joinpath("..", "demo", "demo.jl"))
+    end
 end