Typing tweaks.

cylc/flow/exceptions.py

@@ -18,6 +18,7 @@
 import errno
 from textwrap import wrap
 from typing import (
+    TYPE_CHECKING,
     Callable,
     Dict,
     Iterable,
@@ -28,10 +29,13 @@
     Union,
 )
 
-from cylc.flow.subprocctx import SubFuncContext
 from cylc.flow.util import format_cmd
 
 
+if TYPE_CHECKING:
+    from cylc.flow.subprocctx import SubFuncContext
+
+
 class CylcError(Exception):
     """Generic exception for Cylc errors.
 
@@ -198,7 +202,7 @@ def __init__(
         message: str,
         platform_name: str,
         *,
-        ctx: Optional[SubFuncContext] = None,
+        ctx: Optional['SubFuncContext'] = None,
         cmd: Optional[Union[str, Iterable]] = None,
         ret_code: Optional[int] = None,
         out: Optional[str] = None,

cylc/flow/flow_mgr.py

@@ -16,11 +16,18 @@
 
 """Manage flow counter and flow metadata."""
 
-from typing import Dict, Set, Optional
+from typing import (
+    Dict,
+    Set,
+    Optional,
+    TYPE_CHECKING
+)
 import datetime
 
 from cylc.flow import LOG
-from cylc.flow.workflow_db_mgr import WorkflowDatabaseManager
+
+if TYPE_CHECKING:
+    from cylc.flow.workflow_db_mgr import WorkflowDatabaseManager
 
 
 FlowNums = Set[int]

cylc/flow/job_runner_handlers/documentation.py

@@ -22,13 +22,16 @@
 not intended to be subclassed.
 """
 
-import re
 from typing import (
     Iterable,
     List,
     Tuple,
+    TYPE_CHECKING
 )
 
+if TYPE_CHECKING:
+    import re
+
 
 class ExampleHandler():
     """Documentation for writing job runner handlers.
@@ -258,15 +261,15 @@ class QSUBHandler(PBSHandler):
 
     """
 
-    REC_ID_FROM_SUBMIT_OUT: re.Pattern
+    REC_ID_FROM_SUBMIT_OUT: 're.Pattern'
     """Regular expression to extract job IDs from submission stderr.
 
     A regular expression (compiled) to extract the job "id" from the standard
     output or standard error of the job submission command.
 
     """
 
-    REC_ID_FROM_SUBMIT_ERR: re.Pattern
+    REC_ID_FROM_SUBMIT_ERR: 're.Pattern'
     """Regular expression to extract job IDs from submission stderr.
 
     See :py:attr:`ExampleHandler.REC_ID_FROM_SUBMIT_OUT`.

cylc/flow/network/server.py

@@ -21,7 +21,6 @@
 from time import sleep
 from typing import TYPE_CHECKING, Any, Dict, Iterable, List, Optional, Union
 
-from graphql.execution import ExecutionResult
 from graphql.execution.executors.asyncio import AsyncioExecutor
 import zmq
 from zmq.auth.thread import ThreadAuthenticator
@@ -41,7 +40,7 @@
 
 if TYPE_CHECKING:
     from cylc.flow.scheduler import Scheduler
-
+    from graphql.execution import ExecutionResult
 
 # maps server methods to the protobuf message (for client/UIS import)
 PB_METHOD_MAP = {
@@ -368,7 +367,7 @@ def graphql(
             object: Execution result, or a list with errors.
         """
         try:
-            executed: ExecutionResult = schema.execute(
+            executed: 'ExecutionResult' = schema.execute(
                 request_string,
                 variable_values=variables,
                 context_value={

cylc/flow/parsec/fileparse.py

@@ -31,11 +31,12 @@
 """
 
 import os
-from optparse import Values
 from pathlib import Path
 import re
 import sys
-import typing as t
+from typing import (
+    Dict, Any, Optional, List, TYPE_CHECKING
+)
 
 from cylc.flow import __version__, iter_entry_points
 from cylc.flow import LOG
@@ -50,6 +51,8 @@
 from cylc.flow.workflow_files import (
     get_workflow_source_dir, check_flow_file)
 
+if TYPE_CHECKING:
+    from optparse import Values
 
 # heading/sections can contain commas (namespace name lists) and any
 # regex pattern characters (this was for pre cylc-6 satellite tasks).
@@ -304,9 +307,9 @@ def process_plugins(fpath, opts):
 
 
 def merge_template_vars(
-    native_tvars: t.Dict[str, t.Any],
-    plugin_result: t.Dict[str, t.Any]
-) -> t.Dict[str, t.Any]:
+    native_tvars: Dict[str, Any],
+    plugin_result: Dict[str, Any]
+) -> Dict[str, Any]:
     """Manage the merger of Cylc Native and Plugin template variables.
 
     Args:
@@ -347,7 +350,7 @@ def merge_template_vars(
         return native_tvars
 
 
-def _prepend_old_templatevars(fpath: str, template_vars: t.Dict) -> t.Dict:
+def _prepend_old_templatevars(fpath: str, template_vars: Dict) -> Dict:
     """If the fpath is in a rundir, extract template variables from database.
 
     Args:
@@ -386,10 +389,10 @@ def _get_fpath_for_source(fpath: str, opts: "Values") -> str:
 
 def read_and_proc(
     fpath: str,
-    template_vars: t.Optional[t.Dict[str, t.Any]] = None,
-    viewcfg: t.Any = None,
-    opts: t.Any = None,
-) -> t.List[str]:
+    template_vars: Optional[Dict[str, Any]] = None,
+    viewcfg: Any = None,
+    opts: Any = None,
+) -> List[str]:
     """
     Read a cylc parsec config file (at fpath), inline any include files,
     process with Jinja2, and concatenate continuation lines.
@@ -516,8 +519,8 @@ def read_and_proc(
 
 
 def hashbang_and_plugin_templating_clash(
-    templating: str, flines: t.List[str]
-) -> t.Optional[str]:
+    templating: str, flines: List[str]
+) -> Optional[str]:
     """Return file's hashbang/shebang, but raise TemplateVarLanguageClash
     if plugin-set template engine and hashbang do not match.
 
@@ -544,7 +547,7 @@ def hashbang_and_plugin_templating_clash(
                 ...
             cylc.flow.parsec.exceptions.TemplateVarLanguageClash: ...
     """
-    hashbang: t.Optional[str] = None
+    hashbang: Optional[str] = None
     # Get hashbang if possible:
     if flines:
         match = re.match(r'^#!(\S+)', flines[0])
@@ -564,9 +567,9 @@ def hashbang_and_plugin_templating_clash(
 
 def parse(
     fpath: str,
-    output_fname: t.Optional[str] = None,
-    template_vars: t.Optional[t.Dict[str, t.Any]] = None,
-    opts: t.Any = None,
+    output_fname: Optional[str] = None,
+    template_vars: Optional[Dict[str, Any]] = None,
+    opts: Any = None,
 ) -> OrderedDictWithDefaults:
     """Parse file items line-by-line into a corresponding nested dict."""
 
@@ -579,7 +582,7 @@ def parse(
 
     nesting_level = 0
     config = OrderedDictWithDefaults()
-    parents: t.List[str] = []
+    parents: List[str] = []
 
     maxline = len(flines) - 1
     index = -1

cylc/flow/scheduler.py

@@ -18,7 +18,6 @@
 import asyncio
 from contextlib import suppress
 from collections import deque
-from optparse import Values
 import os
 import inspect
 from pathlib import Path
@@ -86,7 +85,6 @@
 from cylc.flow.timer import Timer
 from cylc.flow.network import API
 from cylc.flow.network.authentication import key_housekeeping
-from cylc.flow.network.resolvers import TaskMsg
 from cylc.flow.network.schema import WorkflowStopMode
 from cylc.flow.network.server import WorkflowRuntimeServer
 from cylc.flow.option_parsers import (
@@ -155,6 +153,8 @@
     # FROM: Python 3.7
     # TO: Python 3.8
     from typing_extensions import Literal
+    from optparse import Values
+    from cylc.flow.network.resolvers import TaskMsg
 
 
 class SchedulerStop(CylcError):
@@ -228,7 +228,7 @@ class Scheduler:
 
     # configuration
     config: WorkflowConfig  # flow config
-    options: Values
+    options: 'Values'
     cylc_config: DictTree  # [scheduler] config
     template_vars: Dict[str, Any]
 
@@ -271,7 +271,7 @@ class Scheduler:
 
     time_next_kill: Optional[float] = None
 
-    def __init__(self, id_: str, options: Values) -> None:
+    def __init__(self, id_: str, options: 'Values') -> None:
         # flow information
         self.workflow = id_
         self.workflow_name = get_workflow_name_from_id(self.workflow)
@@ -875,7 +875,7 @@ def _load_task_run_times(self, row_idx, row):
 
     def process_queued_task_messages(self) -> None:
         """Handle incoming task messages for each task proxy."""
-        messages: Dict[str, List[Tuple[Optional[int], TaskMsg]]] = {}
+        messages: Dict[str, List[Tuple[Optional[int], 'TaskMsg']]] = {}
         while self.message_queue.qsize():
             try:
                 task_msg = self.message_queue.get(block=False)

cylc/flow/scripts/kill.py

@@ -34,7 +34,6 @@
 from functools import partial
 from typing import TYPE_CHECKING
 
-from cylc.flow.id import Tokens
 from cylc.flow.network.client_factory import get_client
 from cylc.flow.network.multi import call_multi
 from cylc.flow.option_parsers import (
@@ -45,6 +44,7 @@
 
 if TYPE_CHECKING:
     from optparse import Values
+    from cylc.flow.id import Tokens
 
 
 MUTATION = '''
@@ -74,7 +74,7 @@ def get_option_parser() -> COP:
     return parser
 
 
-async def run(options: 'Values', workflow_id: str, *tokens_list: Tokens):
+async def run(options: 'Values', workflow_id: str, *tokens_list: 'Tokens'):
     pclient = get_client(workflow_id, timeout=options.comms_timeout)
 
     mutation_kwargs = {

cylc/flow/scripts/set_outputs.py

@@ -48,7 +48,7 @@
 """
 
 from functools import partial
-from optparse import Values
+from typing import TYPE_CHECKING
 
 from cylc.flow.network.client_factory import get_client
 from cylc.flow.network.multi import call_multi
@@ -58,6 +58,10 @@
 )
 from cylc.flow.terminal import cli_function
 
+if TYPE_CHECKING:
+    from optparse import Values
+
+
 MUTATION = '''
 mutation (
   $wFlows: [WorkflowID]!,

cylc/flow/scripts/set_verbosity.py

@@ -26,7 +26,7 @@
 """
 
 from functools import partial
-from optparse import Values
+from typing import TYPE_CHECKING
 
 from cylc.flow import LOG_LEVELS
 from cylc.flow.exceptions import InputError
@@ -38,6 +38,10 @@
 )
 from cylc.flow.terminal import cli_function
 
+if TYPE_CHECKING:
+    from optparse import Values
+
+
 MUTATION = '''
 mutation (
   $wFlows: [WorkflowID]!,

cylc/flow/scripts/validate.py

@@ -26,10 +26,11 @@
 """
 
 import asyncio
+import sys
+
 from ansimarkup import parse as cparse
 from copy import deepcopy
-from optparse import Values
-import sys
+from typing import TYPE_CHECKING
 
 from cylc.flow import LOG, __version__ as CYLC_VERSION
 from cylc.flow.config import WorkflowConfig
@@ -56,6 +57,8 @@
 from cylc.flow.terminal import cli_function
 from cylc.flow.scheduler_cli import RUN_MODE
 
+if TYPE_CHECKING:
+    from optparse import Values
 
 VALIDATE_RUN_MODE = deepcopy(RUN_MODE)
 VALIDATE_RUN_MODE.sources = {'validate'}

cylc/flow/subprocpool.py

@@ -76,7 +76,7 @@ def get_func(mod_name, func_name, src_dir):
 
     Raises:
         ImportError, if the module is not found
-        AtributeError, if the function is not found in the module
+        AttributeError, if the function is not found in the module
 
     """
     if func_name in _XTRIG_FUNCS:

cylc/flow/task_events_mgr.py

@@ -581,7 +581,7 @@ def process_message(
         if submit_num is None:
             submit_num = itask.submit_num
         if isinstance(severity, int):
-            severity = cast(str, getLevelName(severity))
+            severity = cast('str', getLevelName(severity))
         lseverity = str(severity).lower()
 
         # Any message represents activity.
@@ -811,7 +811,7 @@ def _process_message_check(
                 )
             return False
 
-        severity = cast(int, LOG_LEVELS.get(severity, INFO))
+        severity = cast('int', LOG_LEVELS.get(severity, INFO))
         # Demote log level to DEBUG if this is a message that duplicates what
         # gets logged by itask state change anyway (and not manual poll)
         if severity > DEBUG and flag != self.FLAG_POLLED and message in {