Tests: modern PEP8-ify core test modules and methods (#2298)

* rename modules

* rename methods

* add docstrings to the general tests

* add base import stub

* test_base -> bases

* print deprecation warning

* redo 2346

test/general/test_reachability.py

@@ -0,0 +1,71 @@
+import unittest
+
+from BaseClasses import CollectionState
+from worlds.AutoWorld import AutoWorldRegister
+from . import setup_solo_multiworld
+
+
+class TestBase(unittest.TestCase):
+    gen_steps = ["generate_early", "create_regions", "create_items", "set_rules", "generate_basic", "pre_fill"]
+
+    default_settings_unreachable_regions = {
+        "A Link to the Past": {
+            "Chris Houlihan Room",  # glitch room by definition
+            "Desert Northern Cliffs",  # on top of mountain, only reachable via OWG
+            "Dark Death Mountain Bunny Descent Area"  # OWG Mountain descent
+        },
+        "Ocarina of Time": {
+            "Prelude of Light Warp",  # Prelude is not progression by default
+            "Serenade of Water Warp",  # Serenade is not progression by default
+            "Lost Woods Mushroom Timeout",  # trade quest starts after this item
+            "ZD Eyeball Frog Timeout",  # trade quest starts after this item
+            "ZR Top of Waterfall",  # dummy region used for entrance shuffle
+        },
+        # The following SM regions are only used when the corresponding StartLocation option is selected (so not with
+        # default settings). Also, those don't have any entrances as they serve as starting Region (that's why they
+        # have to be excluded for testAllStateCanReachEverything).
+        "Super Metroid": {
+            "Ceres",
+            "Gauntlet Top",
+            "Mama Turtle"
+        }
+    }
+
+    def test_default_all_state_can_reach_everything(self):
+        """Ensure all state can reach everything and complete the game with the defined options"""
+        for game_name, world_type in AutoWorldRegister.world_types.items():
+            unreachable_regions = self.default_settings_unreachable_regions.get(game_name, set())
+            with self.subTest("Game", game=game_name):
+                world = setup_solo_multiworld(world_type)
+                excluded = world.exclude_locations[1].value
+                state = world.get_all_state(False)
+                for location in world.get_locations():
+                    if location.name not in excluded:
+                        with self.subTest("Location should be reached", location=location):
+                            self.assertTrue(location.can_reach(state), f"{location.name} unreachable")
+
+                for region in world.get_regions():
+                    if region.name in unreachable_regions:
+                        with self.subTest("Region should be unreachable", region=region):
+                            self.assertFalse(region.can_reach(state))
+                    else:
+                        with self.subTest("Region should be reached", region=region):
+                            self.assertTrue(region.can_reach(state))
+
+                with self.subTest("Completion Condition"):
+                    self.assertTrue(world.can_beat_game(state))
+
+    def test_default_empty_state_can_reach_something(self):
+        """Ensure empty state can reach at least one location with the defined options"""
+        for game_name, world_type in AutoWorldRegister.world_types.items():
+            with self.subTest("Game", game=game_name):
+                world = setup_solo_multiworld(world_type)
+                state = CollectionState(world)
+                all_locations = world.get_locations()
+                if all_locations:
+                    locations = set()
+                    for location in all_locations:
+                        if location.can_reach(state):
+                            locations.add(location)
+                    self.assertGreater(len(locations), 0,
+                                       msg="Need to be able to reach at least one location to get started.")