[PATCH 1/2] perf timechart: Fix task row type narrowing in goto_task()

[James Clark <james.clark@linaro.org>]

Mypy cannot narrow Row to TaskRow or IoRow when the class passed to
isinstance() comes from a loop variable, causing the perf build to fail
with:

  python/ttimechart.py:1686: error: "Row" has no attribute "task" [attr-defined]

Check against TaskRow and IoRow explicitly so mypy can verify access to
the task attribute. The tasks and I/O views contain TaskRow and IoRow
instances respectively, so task navigation behaves as before.

Fixes: e7a72d691980 ("perf timechart: Add an interactive --tui mode")
Assisted-by: Codex:GPT-6.1-Sol
Signed-off-by: James Clark <james.clark@linaro.org>
---
 tools/perf/python/ttimechart.py | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/tools/perf/python/ttimechart.py b/tools/perf/python/ttimechart.py
index 34ecf84e68c1..d7ba0276a9fb 100755
--- a/tools/perf/python/ttimechart.py
+++ b/tools/perf/python/ttimechart.py
@@ -1676,14 +1676,13 @@ class TimechartApp(App):
 
     def goto_task(self, tid: int, time: Optional[float]) -> None:
         """Select the task in the tasks or I/O view, optionally moving the cursor."""
-        for tab_id, view_id, row_type in (("tasks", "#tasks_view", TaskRow),
-                                          ("io", "#io_view", IoRow)):
+        for tab_id, view_id in (("tasks", "#tasks_view"), ("io", "#io_view")):
             views = self.query(view_id)
             if not views:
                 continue
             view = views.first(TimelineView)
             for idx, row in enumerate(view.rows):
-                if isinstance(row, row_type) and row.task.tid == tid:
+                if isinstance(row, (TaskRow, IoRow)) and row.task.tid == tid:
                     self.query_one(TabbedContent).active = tab_id
                     if time is not None:
                         self.window = self.window.with_cursor(time)

-- 
2.43.0