Turn table existence check into a fixture for easier use

tests/conftest.py

@@ -1,5 +1,5 @@
 import pytest
-from sqlalchemy import create_engine
+from sqlalchemy import create_engine, inspect
 from sqlalchemy.engine import make_url
 from sqlalchemy_utils import create_database, database_exists, drop_database
 
@@ -23,3 +23,11 @@ def engine():
 
     # drop the database on test suite exit
     drop_database(url)
+
+
+@pytest.fixture
+def has_table(engine):
+    def checker(table_name):
+        return inspect(engine).has_table(table_name)
+
+    return checker

tests/metrics/timescaledb/test_writer.py

@@ -1,7 +1,7 @@
 from datetime import date
 
 import pytest
-from sqlalchemy import TIMESTAMP, Column, Integer, Table, inspect, select, text
+from sqlalchemy import TIMESTAMP, Column, Integer, Table, select, text
 from sqlalchemy.engine import make_url
 
 from metrics.timescaledb.tables import metadata
@@ -43,15 +43,15 @@ def table():
     )
 
 
-def test_timescaledbwriter(engine, table):
+def test_timescaledbwriter(engine, has_table, table):
     # check ensure_table is setting up the table
-    assert not inspect(engine).has_table(table.name)
+    assert not has_table(table.name)
 
     with TimescaleDBWriter(table, engine) as writer:
         for i in range(1, 4):
             writer.write(date(2023, 11, i), i)
 
-    assert inspect(engine).has_table(table.name)
+    assert has_table(table.name)
 
     # check there are timescaledb child tables
     # https://stackoverflow.com/questions/1461722/how-to-find-child-tables-that-inherit-from-another-table-in-psql