change(aurweb): add parallel tests and improve aurweb.db

This change utilizes pytest-xdist to perform a multiproc test
run and reworks aurweb.db's code. We no longer use a global
engine, session or Session, but we now use a memo of engines
and sessions as they are requested, based on the PYTEST_CURRENT_TEST
environment variable, which is available during testing.

Additionally, this change strips several SQLite components
out of the Python code-base.

SQLite is still compatible with PHP and sharness tests, but
not with our FastAPI implementation.

More changes:
------------
- Remove use of aurweb.db.session global in other code.
- Use new aurweb.db.name() dynamic db name function in env.py.
- Added 'addopts' to pytest.ini which utilizes multiprocessing.
    - Highly recommended to leave this be or modify `-n auto` to
      `-n {cpu_threads}` where cpu_threads is at least 2.

Signed-off-by: Kevin Morris <kevr@0cost.org>

test/test_package_comment.py

@@ -2,70 +2,55 @@ import pytest
 
 from sqlalchemy.exc import IntegrityError
 
-from aurweb.db import begin, create, query, rollback
-from aurweb.models.account_type import AccountType
+from aurweb import db
+from aurweb.models.account_type import USER_ID
 from aurweb.models.package_base import PackageBase
 from aurweb.models.package_comment import PackageComment
 from aurweb.models.user import User
-from aurweb.testing import setup_test_db
 
 user = pkgbase = None
 
 
 @pytest.fixture(autouse=True)
-def setup():
-    setup_test_db("PackageBases", "PackageComments", "Users")
-
+def setup(db_test):
     global user, pkgbase
 
-    account_type = query(AccountType,
-                         AccountType.AccountType == "User").first()
-    with begin():
-        user = create(User, Username="test", Email="test@example.org",
-                      RealName="Test User", Passwd="testPassword",
-                      AccountType=account_type)
-        pkgbase = create(PackageBase, Name="test-package", Maintainer=user)
+    with db.begin():
+        user = db.create(User, Username="test", Email="test@example.org",
+                         RealName="Test User", Passwd="testPassword",
+                         AccountTypeID=USER_ID)
+        pkgbase = db.create(PackageBase, Name="test-package", Maintainer=user)
 
 
 def test_package_comment_creation():
-    with begin():
-        package_comment = create(PackageComment,
-                                 PackageBase=pkgbase,
-                                 User=user,
-                                 Comments="Test comment.",
-                                 RenderedComment="Test rendered comment.")
+    with db.begin():
+        package_comment = db.create(PackageComment, PackageBase=pkgbase,
+                                    User=user, Comments="Test comment.",
+                                    RenderedComment="Test rendered comment.")
     assert bool(package_comment.ID)
 
 
 def test_package_comment_null_package_base_raises_exception():
     with pytest.raises(IntegrityError):
-        with begin():
-            create(PackageComment, User=user, Comments="Test comment.",
-                   RenderedComment="Test rendered comment.")
-    rollback()
+        PackageComment(User=user, Comments="Test comment.",
+                       RenderedComment="Test rendered comment.")
 
 
 def test_package_comment_null_user_raises_exception():
     with pytest.raises(IntegrityError):
-        with begin():
-            create(PackageComment, PackageBase=pkgbase,
-                   Comments="Test comment.",
-                   RenderedComment="Test rendered comment.")
-    rollback()
+        PackageComment(PackageBase=pkgbase,
+                       Comments="Test comment.",
+                       RenderedComment="Test rendered comment.")
 
 
 def test_package_comment_null_comments_raises_exception():
     with pytest.raises(IntegrityError):
-        with begin():
-            create(PackageComment, PackageBase=pkgbase, User=user,
-                   RenderedComment="Test rendered comment.")
-    rollback()
+        PackageComment(PackageBase=pkgbase, User=user,
+                       RenderedComment="Test rendered comment.")
 
 
 def test_package_comment_null_renderedcomment_defaults():
-    with begin():
-        record = create(PackageComment,
-                        PackageBase=pkgbase,
-                        User=user,
-                        Comments="Test comment.")
+    with db.begin():
+        record = db.create(PackageComment, PackageBase=pkgbase,
+                           User=user, Comments="Test comment.")
     assert record.RenderedComment == str()