Allow tests to bypass automatic setting of [scheduler]allow implicit …

…tasks = True

tests/integration/scripts/test_validate_integration.py

@@ -139,7 +139,7 @@ def test_pre_cylc8(flow, validate, caplog):
                 'events': {'reset timer': 20}
             }
         }
-    })
+    }, defaults=False)
     validate(id_)
     for warning in (
         (

tests/integration/utils/flow_tools.py

@@ -56,8 +56,16 @@ def _make_flow(
     conf: dict,
     name: Optional[str] = None,
     id_: Optional[str] = None,
+    defaults: Optional[bool] = True,
 ) -> str:
-    """Construct a workflow on the filesystem."""
+    """Construct a workflow on the filesystem.
+
+    Args:
+        defaults: Set up a common defaults.
+            * [scheduling]allow implicit tasks = true
+
+            Set false for Cylc 7 upgrader tests.
+    """
     if id_:
         flow_run_dir = (cylc_run_dir / id_)
     else:
@@ -74,7 +82,10 @@ def _make_flow(
         .setdefault('default run length', 'PT0S')
     )
     # allow implicit tasks by default:
-    conf.setdefault('scheduler', {}).setdefault('allow implicit tasks', 'True')
+    if defaults:
+        conf.setdefault('scheduler', {}).setdefault(
+            'allow implicit tasks', 'True')
+
     with open((flow_run_dir / WorkflowFiles.FLOW_FILE), 'w+') as flow_file:
         flow_file.write(flow_config_str(conf))
     return id_