[Autoloop] [Autoloop: perf-comparison]

🤖 *This PR is maintained by Autoloop. Each accepted iteration adds a commit to this branch.*

## Goal

Systematically benchmark every tsb function against its pandas equivalent, one function per iteration. Results are published to the playground benchmarks page.

**Current best metric**: 643 benchmark pairs

## Latest iteration (290)

Added 5 new benchmark pairs:
- `string_accessor_lower_strip` — `str.lower()` + `str.strip()` on 100k strings
- `string_accessor_len_replace` — `str.len()` + `str.replace()` on 100k strings
- `string_accessor_split_join` — `str.split()` on 100k strings
- `insert_pop_column` — `insertColumn` + `popColumn` on 10k-row DataFrame
- `natsort_strings` — `natSorted` on 10k natural-order strings

Total: 508 → 643 benchmark pairs accumulated on this branch.

> Generated by [Autoloop](https://github.com/githubnext/tsessebe/actions/runs/24919519451/agentic_workflow) · ● 1.9M · [◷](https://github.com/search?q=repo%3Agithubnext%2Ftsessebe+%22gh-aw-workflow-id%3A+autoloop%22&type=pullrequests)

---

> [!NOTE]
> This was originally intended as a pull request, but the git push operation failed.
>
> **Workflow Run:** [View run details and download patch artifact](https://github.com/githubnext/tsessebe/actions/runs/24919519451)
>
> The patch file is available in the `agent` artifact in the workflow run linked above.

To create a pull request with the changes:

```sh
# Download the artifact from the workflow run
gh run download 24919519451 -n agent -D /tmp/agent-24919519451

# Create a new branch
git checkout -b autoloop/perf-comparison

# Apply the patch (--3way handles cross-repo patches where files may already exist)
git am --3way /tmp/agent-24919519451/aw-autoloop-perf-comparison.patch

# Push the branch to origin
git push origin autoloop/perf-comparison

# Create the pull request
gh pr create --title '[Autoloop] [Autoloop: perf-comparison]' --base main --head autoloop/perf-comparison --repo githubnext/tsessebe
```

Show patch preview (396 of 396 lines)

```diff
From fa861a099486416627401d4543a1eff2f98ab1fb Mon Sep 17 00:00:00 2001
From: "github-actions[bot]"
Date: Sat, 25 Apr 2026 01:43:50 +0000
Subject: [PATCH] [Autoloop: perf-comparison] Iteration 290: add 5 benchmark
pairs (string_accessor lower/strip, len/replace, split/join, insert_pop,
natsort)

Run: https://github.com/githubnext/tsessebe/actions/runs/24919519451

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
benchmarks/pandas/bench_insert_pop_column.py | 33 +++++++++++++++++
benchmarks/pandas/bench_natsort_strings.py | 29 +++++++++++++++
.../bench_string_accessor_len_replace.py | 27 ++++++++++++++
.../bench_string_accessor_lower_strip.py | 27 ++++++++++++++
.../bench_string_accessor_split_join.py | 25 +++++++++++++
benchmarks/tsb/bench_insert_pop_column.ts | 35 +++++++++++++++++++
benchmarks/tsb/bench_natsort_strings.ts | 29 +++++++++++++++
.../tsb/bench_string_accessor_len_replace.ts | 32 +++++++++++++++++
.../tsb/bench_string_accessor_lower_strip.ts | 32 +++++++++++++++++
.../tsb/bench_string_accessor_split_join.ts | 30 ++++++++++++++++
10 files changed, 299 insertions(+)
create mode 100644 benchmarks/pandas/bench_insert_pop_column.py
create mode 100644 benchmarks/pandas/bench_natsort_strings.py
create mode 100644 benchmarks/pandas/bench_string_accessor_len_replace.py
create mode 100644 benchmarks/pandas/bench_string_accessor_lower_strip.py
create mode 100644 benchmarks/pandas/bench_string_accessor_split_join.py
create mode 100644 benchmarks/tsb/bench_insert_pop_column.ts
create mode 100644 benchmarks/tsb/bench_natsort_strings.ts
create mode 100644 benchmarks/tsb/bench_string_accessor_len_replace.ts
create mode 100644 benchmarks/tsb/bench_string_accessor_lower_strip.ts
create mode 100644 benchmarks/tsb/bench_string_accessor_split_join.ts

diff --git a/benchmarks/pandas/bench_insert_pop_column.py b/benchmarks/pandas/bench_insert_pop_col
... (truncated)
```