Merge branch 'fix.platform_is_regex_remote_tidy_fail' of github.com:w…

…xtim/cylc into fix.platform_is_regex_remote_tidy_fail

* 'fix.platform_is_regex_remote_tidy_fail' of github.com:wxtim/cylc:
  Apply suggestions from code review
  Update cylc/flow/exceptions.py

cylc/flow/exceptions.py

@@ -438,9 +438,9 @@ def __str__(self):
 class NoPlatformsError(CylcError):
     """None of the platforms of a given set were reachable.
 
-    Instatiation args:
+    Args:
         identity: The name of the platform group or install target
-        _type: Whether the set of platforms is a platform group or an
+        set_type: Whether the set of platforms is a platform group or an
             install target
         place: Where the attempt to get the platform failed.
     """

cylc/flow/task_remote_mgr.py

@@ -290,7 +290,7 @@ def construct_remote_tidy_ssh_cmd(
 
     @staticmethod
     def _get_remote_tidy_targets(
-        platform_names: List[str],
+        platform_names: Optional[List[str]],
         install_targets: Set[str]
     ) -> Dict[str, List[Dict[str, Any]]]:
         """Finds valid platforms for install targets, warns about in invalid
@@ -311,9 +311,7 @@ def _get_remote_tidy_targets(
 
         # If we couldn't find a platform for a target, we cannot tidy it -
         # raise an Error:
-        unreachable_targets = {
-            t for t in install_targets if not install_targets_map.get(t)
-        }
+        unreachable_targets = install_targets.difference(install_targets_map)
         if unreachable_targets:
             msg = 'No platforms available to remote tidy install targets:'
             for unreachable_target in unreachable_targets:

tests/unit/test_rundb.py

@@ -160,16 +160,16 @@ def test_select_platforms_used(tmp_path):
     """
     # Setup DB
     db_file = tmp_path / 'db'
-    dao = CylcWorkflowDAO(db_file_name=db_file, create_tables=True)
-
-    # Write database with 6 tasks using 3 platforms:
-    platforms = ['foo', 'bar', 'bar', 'qux', 'qux', 'qux']
-    line = (
-        r"    ('', '', {}, 0, 1, '', '', 0, '', '', '', 0, '', '{}', 4377, '')")
-    stmt = r"INSERT INTO task_jobs VALUES" + r','.join([
-        line.format(i, platform) for i, platform in enumerate(platforms)
-    ])
-    dao.conn.execute(stmt)
-
-    # Assert that we only have 3 platforms reported by function:
-    assert dao.select_platforms_used() == {'bar', 'qux', 'foo'}
+    with CylcWorkflowDAO(db_file_name=db_file, create_tables=True) as dao:
+
+        # Write database with 6 tasks using 3 platforms:
+        platforms = ['foo', 'bar', 'bar', 'qux', 'qux', 'qux']
+        line = (
+            r"    ('', '', {}, 0, 1, '', '', 0, '', '', '', 0, '', '{}', 4377, '')")
+        stmt = r"INSERT INTO task_jobs VALUES" + r','.join([
+            line.format(i, platform) for i, platform in enumerate(platforms)
+        ])
+        dao.conn.execute(stmt)
+
+        # Assert that we only have 3 platforms reported by function:
+        assert dao.select_platforms_used() == {'bar', 'qux', 'foo'}

tests/unit/test_task_remote_mgr.py

@@ -148,7 +148,7 @@ def test_get_log_file_name(tmp_path: Path,
             id='basic'
         ),
         pytest.param(
-            # Two platforms share an install target. Both are reachable.
+            # Two platforms share an install target. Both are unreachable.
             None,
             ['mountain_railway'],
             '''