Testing/integration tests

[akmal-threepointsix]

Since this old PR #351 diverged too much from the up-to-date develop branch, I decided to create a new branch from the develop and open this new PR.

These changes are basically the same as in PR #351:

• Added ImGUI Test Engine submodule (CMakeLists.txt, emulator/lib/ImGUI_TestEngine). IMPORTANT: since I added new submodule, you need to run $ git submodule update --init --recursive after checkout to this branch
• Updated ImGUI, because older version was incompatible with ImGUI Test Engine (emulator/lib/ImGUI)
• Added UI tests for Alarm and Timer (emulator/src/UiTests/OswAppAlarm.cpp, emulator/src/UiTests/OswAppTimer.cpp)
• Updated README.md with new testing chapter
• I didn't change any production code, because testing must not interfere with business logic. I only added three friend classes in three header files (emulator/include/Emulator.hpp, include/apps/OswAppDrawer.h and include/apps/OswAppV2Compat.h)

And some NEW changes:

• I fixed all errors related to the newest PR #358. It made my UI testing code a bit uglier (e.g. I had to use a lot of casting), but at the time I am writing this, everything at least works...
• In UiTest_main.hpp, I added some code to skip tutorial, if emulator was launched with --ui_tests option

[simonmicro]

Hi,
thanks for your work - again! So two things I've noted here...

1. Meh - le pipeline is failing...
2. Could you reorder the code to bundle all the unit/ui/helpers stuff for testing under src/tests again? You've moved them out and put them into the "regular" code. Do not worry, if you won't do it I'll clean that up 😉

After you put so much work into it to re-submit this PR I'll absolutely make sure to get it merged this time. This is the next thing going in - so I'll not allow this to run out-of-sync again! Hehe...

P.S. There is so much code, I'll try to dive deeper into it at a later date - for now I also have too much of my own work going on...

[akmal-threepointsix]

1. Meh - le pipeline is failing...

Fixed (hopefully) by pushing ImGui Test Engine submodule folder

2. Could you reorder the code to bundle all the unit/ui/helpers stuff for testing under src/tests again? You've moved them out and put them into the "regular" code. Do not worry, if you won't do it I'll clean that up 😉

Done. I forgot about this one :)

p.s: in my last PR it wasn't your fault, we were playing with rebases and the situation got out of hand :) Old commits were rebased and git thought they were new commits, because their hash was different. At least I think that's what happened... Anyway, it was too painful to fix...

[akmal-threepointsix]

Ok, I also removed reinterpret_cast from tests/helpers/TestDrawer.h.

It turned out, that OswAppV1 and OswApp are the same class, so I can simply static_cast timer and alarm from OswAppV1 to OswAppTimer and OswAppAlarm respectively, because they are inherited from OswApp

[simonmicro]

@akmal-threepointsix If you formulate that like this... Ever thought about the more safe variant of https://en.cppreference.com/w/cpp/language/dynamic_cast ? This also ensures you won't cast in the future if we break it 😉

[akmal-threepointsix]

Yes, sure, dynamic_cast is also a valid option and safer one. However, it introduces some run-time overhead, which in this case seemed unnecessary to me. On the other hand, you are right, in future someone might change codebase and static_cast will silently fail, so it would be better to use dynamic_cast. I believe, run-time cost is insignificant, especially since it is in emulator & UI tests environment, not in production.

[akmal-threepointsix]

@akmal-threepointsix If you formulate that like this... Ever thought about the more safe variant of https://en.cppreference.com/w/cpp/language/dynamic_cast ? This also ensures you won't cast in the future if we break it 😉

Ok, done. Changed static_cast to dynamic_cast and added assert to confirm that casting was successful and didn't return nullptr