Built-in sandbox SHIM: a pytest-compatible module for the model's Python
sandbox, implemented PURELY in Python on the stdlib (ast, inspect,
linecache, traceback, warnings, tempfile) — NO host/JVM bridge, NOT a
line of Clojure or babashka. pytest is a third-party wheel that does not
ship in GraalPy, so agents writing full Python extensions and wanting to
TEST them inline would otherwise hit ModuleNotFoundError; this extension
contributes a :ext/sandbox-shims entry that
env-python/build-agent-context installs into every sandbox Context (main +
every sub_loop fork).
It is NOT real pytest: there is no pluggy/plugin system, no ini/plugin CLI
(only -k / -x / --maxfail / -v), and no import-time assertion
rewrite. It DOES do conftest.py fixture discovery
(walked from the test file's dir up to the fs root, outer→inner) in disk
mode. Instead it
implements the subset that matters in an inline sandbox where the model
writes tests + pytest.main() in ONE block:
test_* functions and Test* classes (scoped to the
CURRENT block via __vis_src__, so leftovers from earlier blocks in the
shared globals are NOT swept in),assert 2 == 3 reconstructed with operand
values) done by registering __vis_src__ into linecache and walking
the failing frame's AST — the same UX as pytest's rewrite, via a
different mechanism,pytest.raises / warns / approx / fail / skip / xfail /
importorskip, @pytest.fixture (function/module/session scope,
yield-teardown, autouse, recursive injection, parametrized fixtures via
params/ids with request.param, request.getfixturevalue chains),
@pytest.mark.parametrize (incl. indirect=) / skip / skipif / xfail
/ usefixtures (+ arbitrary marks), pytest.param,
builtin fixtures request / monkeypatch / capsys / capfd /
tmp_path / tmp_path_factory / tmpdir / tmpdir_factory /
caplog / recwarn / pytester / testdir, conftest.py fixture discovery,
and a pytest.main() runner (with -k keyword selection, -x /
--maxfail fail-fast, and -v) that prints progress + failure reports
Unlike shim-yaml/shim-matplotlib there are NO :shim/bindings: the shim
is a self-contained Python preamble with zero host callables. It publishes a
pytest module into sys.modules (so import pytest works) and staples it
onto builtins (so pytest.raises(...) works with NO import, like
json/os/requests).
Built-in sandbox SHIM: a `pytest`-compatible module for the model's Python
sandbox, implemented PURELY in Python on the stdlib (`ast`, `inspect`,
`linecache`, `traceback`, `warnings`, `tempfile`) — NO host/JVM bridge, NOT a
line of Clojure or babashka. `pytest` is a third-party wheel that does not
ship in GraalPy, so agents writing full Python extensions and wanting to
TEST them inline would otherwise hit ModuleNotFoundError; this extension
contributes a `:ext/sandbox-shims` entry that
`env-python/build-agent-context` installs into every sandbox Context (main +
every `sub_loop` fork).
It is NOT real pytest: there is no pluggy/plugin system, no ini/plugin CLI
(only `-k` / `-x` / `--maxfail` / `-v`), and no import-time assertion
rewrite. It DOES do `conftest.py` fixture discovery
(walked from the test file's dir up to the fs root, outer→inner) in disk
mode. Instead it
implements the subset that matters in an inline sandbox where the model
writes tests + `pytest.main()` in ONE block:
- collection of `test_*` functions and `Test*` classes (scoped to the
CURRENT block via `__vis_src__`, so leftovers from earlier blocks in the
shared globals are NOT swept in),
- RUNTIME assert introspection (`assert 2 == 3` reconstructed with operand
values) done by registering `__vis_src__` into `linecache` and walking
the failing frame's AST — the same UX as pytest's rewrite, via a
different mechanism,
- `pytest.raises` / `warns` / `approx` / `fail` / `skip` / `xfail` /
`importorskip`, `@pytest.fixture` (function/module/session scope,
yield-teardown, autouse, recursive injection, parametrized fixtures via
`params`/`ids` with `request.param`, `request.getfixturevalue` chains),
`@pytest.mark.parametrize` (incl. `indirect=`) / `skip` / `skipif` / `xfail`
/ `usefixtures` (+ arbitrary marks), `pytest.param`,
builtin fixtures `request` / `monkeypatch` / `capsys` / `capfd` /
`tmp_path` / `tmp_path_factory` / `tmpdir` / `tmpdir_factory` /
`caplog` / `recwarn` / `pytester` / `testdir`, `conftest.py` fixture discovery,
and a `pytest.main()` runner (with `-k` keyword selection, `-x` /
`--maxfail` fail-fast, and `-v`) that prints progress + failure reports
+ a summary line (incl. deselected counts) and returns an exit code.
Unlike `shim-yaml`/`shim-matplotlib` there are NO `:shim/bindings`: the shim
is a self-contained Python preamble with zero host callables. It publishes a
`pytest` module into `sys.modules` (so `import pytest` works) and staples it
onto builtins (so `pytest.raises(...)` works with NO import, like
json/os/requests).cljdoc builds & hosts documentation for Clojure/Script libraries
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