Fix workflow-state alt run-dir.

cylc/flow/id_cli.py

@@ -198,6 +198,7 @@ async def parse_ids_async(
     constraint: str = 'tasks',
     max_workflows: Optional[int] = None,
     max_tasks: Optional[int] = None,
+    alt_run_dir: Optional[str] = None,
 ) -> Tuple[Dict[str, List[Tokens]], Any]:
     """Parse IDs from the command line.
 
@@ -294,7 +295,8 @@ async def parse_ids_async(
 
     # infer the run number if not specified the ID (and if possible)
     if infer_latest_runs:
-        _infer_latest_runs(tokens_list, src_path=src_path)
+        _infer_latest_runs(
+            tokens_list, src_path=src_path, alt_run_dir=alt_run_dir)
 
     _validate_number(
         *tokens_list,
@@ -409,13 +411,14 @@ def _validate_workflow_ids(*tokens_list, src_path):
         detect_both_flow_and_suite(src_path)
 
 
-def _infer_latest_runs(tokens_list, src_path):
+def _infer_latest_runs(tokens_list, src_path, alt_run_dir=None):
     for ind, tokens in enumerate(tokens_list):
         if ind == 0 and src_path:
             # source workflow passed in as a path
             continue
         tokens_list[ind] = tokens.duplicate(
-            workflow=infer_latest_run_from_id(tokens['workflow'])
+            workflow=infer_latest_run_from_id(
+                tokens['workflow'], alt_run_dir)
         )
         pass
 

cylc/flow/scripts/workflow_state.py

@@ -162,7 +162,7 @@ def get_option_parser() -> COP:
         help="The top level cylc run directory if non-standard. The "
              "database should be DIR/WORKFLOW_ID/log/db. Use to interrogate "
              "workflows owned by others, etc.; see note above.",
-        metavar="DIR", action="store", dest="run_dir", default=None)
+        metavar="DIR", action="store", dest="alt_run_dir", default=None)
 
     parser.add_option(
         "-s", "--offset",
@@ -196,10 +196,6 @@ def get_option_parser() -> COP:
 
 @cli_function(get_option_parser, remove_opts=["--db"])
 def main(parser: COP, options: 'Values', workflow_id: str) -> None:
-    workflow_id, *_ = parse_id(
-        workflow_id,
-        constraint='workflows',
-    )
 
     if options.use_task_point and options.cycle:
         raise InputError(
@@ -232,10 +228,17 @@ def main(parser: COP, options: 'Values', workflow_id: str) -> None:
         raise InputError(f"invalid status '{options.status}'")
 
     # this only runs locally
-    if options.run_dir:
-        run_dir = expand_path(options.run_dir)
+    if options.alt_run_dir:
+        run_dir = alt_run_dir = expand_path(options.alt_run_dir)
     else:
         run_dir = get_cylc_run_dir()
+        alt_run_dir = None
+
+    workflow_id, *_ = parse_id(
+        workflow_id,
+        constraint='workflows',
+        alt_run_dir=alt_run_dir
+    )
 
     pollargs = {
         'workflow_id': workflow_id,

cylc/flow/workflow_files.py

@@ -862,16 +862,22 @@ def check_reserved_dir_names(name: Union[Path, str]) -> None:
             raise WorkflowFilesError(err_msg.format('run<number>'))
 
 
-def infer_latest_run_from_id(workflow_id: str) -> str:
-    run_dir = Path(get_workflow_run_dir(workflow_id))
-    _, id_ = infer_latest_run(run_dir)
+def infer_latest_run_from_id(
+    workflow_id: str, alt_run_dir: Optional[str] = None
+) -> str:
+    if alt_run_dir is not None:
+        run_dir = Path(alt_run_dir) / Path(workflow_id)
+    else:
+        run_dir = Path(get_workflow_run_dir(workflow_id))
+    _, id_ = infer_latest_run(run_dir, alt_run_dir=alt_run_dir)
     return id_
 
 
 def infer_latest_run(
     path: Path,
     implicit_runN: bool = True,
     warn_runN: bool = True,
+    alt_run_dir: Optional[str] = None,
 ) -> Tuple[Path, str]:
     """Infer the numbered run dir if the workflow has a runN symlink.
 
@@ -890,15 +896,17 @@ def infer_latest_run(
         - WorkflowFilesError if the runN symlink is not valid.
         - InputError if the path does not exist.
     """
-    cylc_run_dir = get_cylc_run_dir()
+    cylc_run_dir = alt_run_dir or get_cylc_run_dir()
     try:
         id_ = str(path.relative_to(cylc_run_dir))
     except ValueError:
         raise ValueError(f"{path} is not in the cylc-run directory")
+
     if not path.exists():
         raise InputError(
             f'Workflow ID not found: {id_}\n(Directory not found: {path})'
         )
+
     if path.name == WorkflowFiles.RUN_N:
         runN_path = path
         if warn_runN: