List of tests to add

At the moment we only have last-frames tests. Although they are useful, it's not enough. We would need to have tests for cli flags, that check videos, etc. This issue will keep a list of tests that need to be added. Please make more suggestions for tests!

Tests that need to be added

• We should have at least one test for each CLI flag.
• We should test that the cascading priorities in the config system work as expected. Ties in with #201
• We should create a test to certify a clean install. See #11.
• Testing video content
• Test that manim runs correctly on all environments/prompts/versions #336
• Regression test for #240
• Test z-order stuff #327
• Test to ensure MovingCamera and ZoomedScene let the camera move as they should. From #388 .
• Test the functionality of asking the user for which scenes to render #523
• There are no tests for the -s flag or the -t flag
• Test for add_fixed_in_frame_mobjects which is used in 3D scenes #569, currently broken
• Tests for SVG images
• @XorUnison Once video tests are implemented reverse_direction should get one
• @XorUnison Test for Brace
• @PhilippImhof Graphical unit test for Text and MarkupText using a fixed font (TTF)