From 3a3949b80b17ff03815f0e39cb90551b17c61d75 Mon Sep 17 00:00:00 2001
From: mergetest <merge@test.local>
Date: Wed, 23 Sep 2026 21:53:20 -0700
Subject: [PATCH] fix(tests): keep __pycache__ out of a clean checkout

A green tests/run-tests.sh run left agentkit/hooks/lib/__pycache__/
behind because test-rewrite-runtime.sh's --prefix-fixture reinvocation
launches python3 with -I (which implies -E and so ignores
PYTHONDONTWRITEBYTECODE) but not -B, so it re-imports rewrite_runtime.py
without bytecode-write protection. .gitignore also didn't exclude
__pycache__/, so agent-run.sh --cmd test then reported the checkout
dirty and finding-ledger.sh evidence refused.

Ignore __pycache__/ and *.pyc, export PYTHONDONTWRITEBYTECODE=1 from
run-tests.sh as defense in depth, add -B to the reinvocation that was
the actual write path, and pin all of it with a new suite that fails
on the unfixed fixture and passes after.

Closes #897

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
---
 .gitignore                             |  6 ++++++
 tests/fixtures/test_rewrite_runtime.py |  6 +++++-
 tests/run-tests.sh                     |  6 ++++++
 tests/test-clean-tree-after-probe.sh   | 29 ++++++++++++++++++++++++++
 4 files changed, 46 insertions(+), 1 deletion(-)
 create mode 100755 tests/test-clean-tree-after-probe.sh

diff --git a/.gitignore b/.gitignore
index be6351ec..820816f1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,12 @@
 tests/tmp/
 plugin/
 
+# CPython writes these when a suite imports the hook's Python modules
+# (e.g. the activation probe); untracked but unignored, they dirty the
+# checkout after a green run (issue #897).
+__pycache__/
+*.pyc
+
 # opencode: @opencode-ai/plugin is a devDependency for typings only (issue
 # #319); node_modules/ is never imported at runtime and never ships (see
 # tests/build-plugin.sh, which copies only opencode/{index.js,package.json}).
diff --git a/tests/fixtures/test_rewrite_runtime.py b/tests/fixtures/test_rewrite_runtime.py
index 6fa564ae..1be7ecd5 100644
--- a/tests/fixtures/test_rewrite_runtime.py
+++ b/tests/fixtures/test_rewrite_runtime.py
@@ -205,7 +205,11 @@ def prefix_fixture(self, body):
         spec = self.root / "prefix-fixture.json"
         spec.write_text(json.dumps({"profile": profile, "records": str(records.root)}))
         native = self.native.replace("'printf fixture'", shlex.quote(issued["command"]))
-        return [sys.executable, "-I", str(Path(__file__).resolve()), "--prefix-fixture", str(spec), native]
+        # -I ignores PYTHONDONTWRITEBYTECODE (it implies -E), and this
+        # reinvocation re-imports RUNTIME at module load before any guard in
+        # __main__ runs, so -B is required here to keep it from writing
+        # agentkit/hooks/lib/__pycache__ into the shipped tree (issue #897).
+        return [sys.executable, "-I", "-B", str(Path(__file__).resolve()), "--prefix-fixture", str(spec), native]
 
     def test_public_prefix_executes_once_with_native_result_and_refuses_replay(self):
         command = self.prefix_fixture('printf "%s|%s|%s\\n" "$PWD" "$1" "$2"\nprintf stderr >&2\nexit 37\n')
diff --git a/tests/run-tests.sh b/tests/run-tests.sh
index bb86e004..09924d4f 100755
--- a/tests/run-tests.sh
+++ b/tests/run-tests.sh
@@ -27,6 +27,12 @@ pin_locale() {
 }
 pin_locale
 
+# Suites that import Python modules (e.g. the activation probe) write
+# __pycache__/ into the shipped tree unless bytecode writes are disabled.
+# Export it here so it reaches every suite subprocess and the probe stays
+# read-only (issue #897).
+export PYTHONDONTWRITEBYTECODE=1
+
 here=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)
 root=$(dirname -- "$here")
 # The plugin root holds both the skills and the hook dispatchers. The hooks are
diff --git a/tests/test-clean-tree-after-probe.sh b/tests/test-clean-tree-after-probe.sh
new file mode 100755
index 00000000..8e0518db
--- /dev/null
+++ b/tests/test-clean-tree-after-probe.sh
@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+# Pins issue #897: a suite that imports the hook's Python modules must never
+# leave __pycache__/ behind in the shipped tree. test-rewrite-runtime.sh's
+# --prefix-fixture reinvocation runs with `-I`, which implies `-E` and so
+# ignores PYTHONDONTWRITEBYTECODE; without an explicit -B on that reinvocation
+# it re-imports agentkit/hooks/lib/rewrite_runtime.py and writes
+# agentkit/hooks/lib/__pycache__/, dirtying an otherwise-clean checkout.
+set -uo pipefail
+
+TEST_NAME='clean tree after probe'
+here=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)
+root=$(dirname -- "$here")
+# shellcheck source=lib/assert.sh
+source "$here/lib/assert.sh"
+
+plugin="$root/agentkit"
+
+before=$(find "$plugin" -name '__pycache__' 2>/dev/null | LC_ALL=C sort)
+assert_eq '' "$before" 'no __pycache__ under agentkit/ before the suite runs'
+
+unset PYTHONDONTWRITEBYTECODE
+(cd -- "$here" && python3 -B fixtures/test_rewrite_runtime.py) > /dev/null 2>&1
+rc=$?
+assert_eq 0 "$rc" 'test_rewrite_runtime.py exits clean'
+
+after=$(find "$plugin" -name '__pycache__' 2>/dev/null | LC_ALL=C sort)
+assert_eq '' "$after" 'no __pycache__ under agentkit/ after running the rewrite-runtime fixture'
+
+finish