Migrations: Add column `group_role_id` to `group_roles` table

* migrations/auth/20221117_01_RDlfx-modify-group-roles-add-group-role-id.py:
  new migration
* tests/unit/auth/test_migrations_add_remove_columns.py: test new migration

2 files changed, 68 insertions, 8 deletions

diff --git a/migrations/auth/20221117_01_RDlfx-modify-group-roles-add-group-role-id.py b/migrations/auth/20221117_01_RDlfx-modify-group-roles-add-group-role-id.py
new file mode 100644
index 0000000..7115bc3
--- /dev/null
+++ b/migrations/auth/20221117_01_RDlfx-modify-group-roles-add-group-role-id.py
@@ -0,0 +1,47 @@
+"""
+Modify 'group_roles': add 'group_role_id'
+
+At this point, there is no data in the `group_roles` table  and therefore, it
+should be safe to simply recreate it.
+"""
+
+from yoyo import step
+
+__depends__ = {'20221116_01_nKUmX-add-privileges-to-group-leader-role'}
+
+steps = [
+    step(
+        "DROP INDEX IF EXISTS idx_tbl_group_roles_cols_group_id",
+        """
+        CREATE INDEX IF NOT EXISTS idx_tbl_group_roles_cols_group_id
+        ON group_roles(group_id)
+        """),
+    step(
+        "DROP TABLE IF EXISTS group_roles",
+        """
+        CREATE TABLE IF NOT EXISTS group_roles(
+            group_id TEXT NOT NULL,
+            role_id TEXT NOT NULL,
+            PRIMARY KEY(group_id, role_id),
+            FOREIGN KEY(group_id) REFERENCES groups(group_id),
+            FOREIGN KEY(role_id) REFERENCES roles(role_id)
+        ) WITHOUT ROWID
+        """),
+    step(
+        """
+        CREATE TABLE IF NOT EXISTS group_roles(
+            group_role_id TEXT PRIMARY KEY,
+            group_id TEXT NOT NULL,
+            role_id TEXT NOT NULL,
+            FOREIGN KEY(group_id) REFERENCES groups(group_id),
+            FOREIGN KEY(role_id) REFERENCES roles(role_id)
+        ) WITHOUT ROWID
+        """,
+        "DROP TABLE IF EXISTS group_roles"),
+    step(
+        """
+        CREATE INDEX IF NOT EXISTS idx_tbl_group_roles_cols_group_id
+        ON group_roles(group_id)
+        """,
+        "DROP INDEX IF EXISTS idx_tbl_group_roles_cols_group_id")
+]
diff --git a/tests/unit/auth/test_migrations_add_remove_columns.py b/tests/unit/auth/test_migrations_add_remove_columns.py
index 89948b3..d149c64 100644
--- a/tests/unit/auth/test_migrations_add_remove_columns.py
+++ b/tests/unit/auth/test_migrations_add_remove_columns.py
@@ -16,7 +16,9 @@ TEST_PARAMS = (
      "privileges", "privilege_category TEXT", True),
     (("20221110_08_23psB-add-privilege-category-and-privilege-description-"
       "columns-to-privileges-table.py"),
-     "privileges", "privilege_description TEXT", True))
+     "privileges", "privilege_description TEXT", True),
+    ("20221117_01_RDlfx-modify-group-roles-add-group-role-id.py", "group_roles",
+     "group_role_id", True))
 
 def found(haystack: str, needle: str) -> bool:
     """Check whether `needle` is found in `haystack`"""
@@ -37,6 +39,13 @@ def applied_successfully(adding: bool, result_str: str, column: str) -> bool:
         return col_was_found
     return not col_was_found
 
+def rolled_back_successfully(adding: bool, result_str: str, column: str) -> bool:
+    """Check that the migration ran successfully"""
+    col_was_found = found(result_str, column)
+    if adding:
+        return not col_was_found
+    return col_was_found
+
 @pytest.mark.unit_test
 @pytest.mark.parametrize(
     "migration_file,the_table,the_column,adding", TEST_PARAMS)
@@ -64,7 +73,9 @@ def test_apply_add_remove_column(# pylint: disable=[too-many-arguments]
 
     assert pristine_before_migration(
         adding, results_before_migration[0], the_column), (
-            "Database inconsistent before applying migration.")
+            f"Column `{the_column}` exists before migration and should not"
+            if adding else
+            f"Column `{the_column}` doesn't exist before migration and it should")
     assert applied_successfully(
         adding, results_after_migration[0], the_column), "Migration failed"
 
@@ -87,15 +98,17 @@ def test_rollback_add_remove_column(# pylint: disable=[too-many-arguments]
     apply_single_migration(backend, the_migration)
     with db.connection(auth_testdb_path) as conn, db.cursor(conn) as cursor:
         cursor.execute(QUERY, (the_table,))
-        results_before_migration = cursor.fetchone()
+        results_before_rollback = cursor.fetchone()
         rollback_single_migration(backend, the_migration)
         cursor.execute(QUERY, (the_table,))
-        results_after_migration = cursor.fetchone()
+        results_after_rollback = cursor.fetchone()
 
     rollback_migrations(backend, older_migrations + [the_migration])
 
     assert pristine_before_migration(
-        not adding, results_before_migration[0], the_column), (
-            "Database inconsistent before applying migration.")
-    assert applied_successfully(
-        not adding, results_after_migration[0], the_column), "Migration failed"
+        not adding, results_before_rollback[0], the_column), (
+            f"Column `{the_column}` doesn't exist before rollback and it should"
+            if adding else
+            f"Column `{the_column}` exists before rollback and should not")
+    assert rolled_back_successfully(
+        adding, results_after_rollback[0], the_column), "Rollback failed"