unsloth/studio/backend/tests/test_sd_cpp_engine.py

494 lines
18 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-only
# Copyright 2026-present the Unsloth AI Inc. team. All rights reserved. See /studio/LICENSE.AGPL-3.0
"""Unit tests for the sd-cli engine + routing (``sd_cpp_engine.py``).
Hermetic: the binary finder is driven against a tmp filesystem, and ``generate``
runs a fake ``subprocess.Popen`` that emits canned lines and writes the output
PNG -- no real ``sd-cli``, no GPU.
"""
from __future__ import annotations
import os
import sys
import time
import types
from pathlib import Path
import pytest
from core.inference import sd_cpp_engine as eng
from core.inference.sd_cpp_engine import (
ENGINE_DIFFUSERS,
ENGINE_SD_CPP,
SdCppEngine,
find_sd_cpp_binary,
find_sd_server_binary,
runtime_env,
select_diffusion_engine,
)
from core.inference.sd_cpp_args import SdCppGenParams, SdCppModelFiles, SdCppUpscaleParams
# ── binary discovery ────────────────────────────────────────────────────────
def _clear_env(monkeypatch):
monkeypatch.delenv("SD_CLI_PATH", raising = False)
monkeypatch.delenv("UNSLOTH_SD_CPP_PATH", raising = False)
def test_find_prefers_sd_cli_path_env(tmp_path, monkeypatch):
_clear_env(monkeypatch)
binary = tmp_path / "sd-cli"
binary.write_text("#!/bin/sh\n")
monkeypatch.setenv("SD_CLI_PATH", str(binary))
# even with PATH empty, the direct env wins
monkeypatch.setattr(eng.shutil, "which", lambda *_a: None)
assert find_sd_cpp_binary() == str(binary)
def test_find_custom_install_dir_build_layout(tmp_path, monkeypatch):
_clear_env(monkeypatch)
root = tmp_path / "sdcpp"
built = root / "build" / "bin" / "sd-cli"
built.parent.mkdir(parents = True)
built.write_text("x")
monkeypatch.setenv("UNSLOTH_SD_CPP_PATH", str(root))
monkeypatch.setattr(eng.shutil, "which", lambda *_a: None)
assert find_sd_cpp_binary() == str(built)
def test_find_falls_back_to_path(tmp_path, monkeypatch):
_clear_env(monkeypatch)
monkeypatch.setattr(eng.Path, "home", staticmethod(lambda: tmp_path / "nohome"))
monkeypatch.setattr(
eng.shutil, "which", lambda stem: "/usr/bin/sd-cli" if stem == "sd-cli" else None
)
assert find_sd_cpp_binary() == "/usr/bin/sd-cli"
def test_find_returns_none_when_absent(tmp_path, monkeypatch):
_clear_env(monkeypatch)
monkeypatch.setattr(eng.Path, "home", staticmethod(lambda: tmp_path / "nohome"))
monkeypatch.setattr(eng.shutil, "which", lambda *_a: None)
assert find_sd_cpp_binary() is None
# ── sd-server discovery ──────────────────────────────────────────────────────
def _clear_server_env(monkeypatch):
monkeypatch.delenv("SD_SERVER_PATH", raising = False)
monkeypatch.delenv("SD_CLI_PATH", raising = False)
monkeypatch.delenv("UNSLOTH_SD_CPP_PATH", raising = False)
def test_find_server_prefers_sd_server_path_env(tmp_path, monkeypatch):
_clear_server_env(monkeypatch)
binary = tmp_path / "sd-server"
binary.write_text("x")
monkeypatch.setenv("SD_SERVER_PATH", str(binary))
monkeypatch.setattr(eng.shutil, "which", lambda *_a: None)
assert find_sd_server_binary() == str(binary)
def test_find_server_build_layout(tmp_path, monkeypatch):
_clear_server_env(monkeypatch)
root = tmp_path / "sdcpp"
built = root / "build" / "bin" / "sd-server"
built.parent.mkdir(parents = True)
built.write_text("x")
monkeypatch.setenv("UNSLOTH_SD_CPP_PATH", str(root))
monkeypatch.setattr(eng.shutil, "which", lambda *_a: None)
assert find_sd_server_binary() == str(built)
def test_find_server_path_fallback(tmp_path, monkeypatch):
_clear_server_env(monkeypatch)
monkeypatch.setattr(eng.Path, "home", staticmethod(lambda: tmp_path / "nohome"))
monkeypatch.setattr(
eng.shutil, "which", lambda stem: "/usr/bin/sd-server" if stem == "sd-server" else None
)
assert find_sd_server_binary() == "/usr/bin/sd-server"
def test_find_server_not_confused_with_sd_cli(tmp_path, monkeypatch):
# A tree that has only sd-cli must NOT be reported as an sd-server (and vice versa),
# so the backend correctly falls back to one-shot when only the CLI is present.
_clear_server_env(monkeypatch)
root = tmp_path / "sdcpp"
(root / "build" / "bin").mkdir(parents = True)
(root / "build" / "bin" / "sd-cli").write_text("x")
monkeypatch.setenv("UNSLOTH_SD_CPP_PATH", str(root))
monkeypatch.setattr(eng.Path, "home", staticmethod(lambda: tmp_path / "nohome"))
monkeypatch.setattr(eng.shutil, "which", lambda *_a: None)
assert find_sd_server_binary() is None
assert find_sd_cpp_binary() == str(root / "build" / "bin" / "sd-cli")
# ── availability / version ──────────────────────────────────────────────────
def test_engine_unavailable_when_no_binary(monkeypatch):
# Force the "no binary anywhere" condition so the test is hermetic even on a host
# that happens to have sd-cli installed.
monkeypatch.setattr(eng, "find_sd_cpp_binary", lambda: None)
e = SdCppEngine(binary = None)
assert e.is_available() is False
assert e.version() is None
def test_engine_version_parsed_and_cached(tmp_path, monkeypatch):
binary = tmp_path / "sd-cli"
binary.write_text("x")
e = SdCppEngine(binary = str(binary))
calls = {"n": 0}
def _fake_run(*_a, **_k):
calls["n"] += 1
return types.SimpleNamespace(
stdout = "stable-diffusion.cpp version master-721\n", stderr = "", returncode = 0
)
monkeypatch.setattr(eng.subprocess, "run", _fake_run)
assert e.version() == "stable-diffusion.cpp version master-721"
assert e.version() == "stable-diffusion.cpp version master-721"
assert calls["n"] == 1 # cached after the first probe
# ── runtime env (bundled shared libs) ───────────────────────────────────────
def test_runtime_env_prepends_binary_dir_to_lib_path():
var = eng._lib_path_var()
env = runtime_env("/opt/sdcpp/bin/sd-cli", {var: "/existing"})
first = env[var].split(os.pathsep)[0]
assert first == "/opt/sdcpp/bin"
assert "/existing" in env[var]
def test_runtime_env_scrubs_native_path_lease_secret(monkeypatch):
# The sd-cli child is an external process and must never receive the native-path
# lease secret; every launch (version + generate/upscale) funnels through runtime_env.
monkeypatch.setenv("UNSLOTH_STUDIO_NATIVE_PATH_LEASE_SECRET", "top-secret")
from_os = runtime_env("/opt/sdcpp/bin/sd-cli")
assert "UNSLOTH_STUDIO_NATIVE_PATH_LEASE_SECRET" not in from_os
from_base = runtime_env(
"/opt/sdcpp/bin/sd-cli",
{"UNSLOTH_STUDIO_NATIVE_PATH_LEASE_SECRET": "top-secret"},
)
assert "UNSLOTH_STUDIO_NATIVE_PATH_LEASE_SECRET" not in from_base
def test_runtime_env_handles_missing_lib_path():
var = eng._lib_path_var()
env = runtime_env("/opt/sdcpp/bin/sd-cli", {})
assert env[var] == "/opt/sdcpp/bin"
def test_terminate_reaps_killed_child():
# Cancellation/timeout paths call _terminate then immediately raise, so it must
# reap the killed child itself -- otherwise a burst of image cancellations leaves
# zombies until a later Popen cleanup. After _terminate the returncode is set
# (the child has been waited on), so nothing lingers.
import subprocess
proc = subprocess.Popen(
[sys.executable, "-c", "import time; time.sleep(30)"],
start_new_session = (os.name == "posix"),
)
try:
eng._terminate(proc)
assert proc.returncode is not None
finally:
if proc.poll() is None:
proc.kill()
proc.wait()
# ── generate (fake subprocess) ──────────────────────────────────────────────
class _FakePopen:
"""Stand-in for subprocess.Popen: streams ``lines`` then writes ``out_file``
(unless ``write`` is False) and exits with ``returncode``."""
captured_cmd: list[str] = []
captured_env: dict = {}
def __init__(
self,
cmd,
*,
lines,
returncode,
out_file,
write,
env = None,
):
type(self).captured_cmd = list(cmd)
type(self).captured_env = dict(env or {})
self._lines = list(lines)
self.returncode = returncode
self._out_file = out_file
self._write = write
@property
def stdout(self):
return iter(self._lines)
def wait(self, timeout = None):
if self._write:
Path(self._out_file).write_bytes(b"\x89PNG\r\n")
return self.returncode
def poll(self):
return self.returncode
def kill(self):
pass
def _patch_popen(
monkeypatch,
*,
lines,
returncode,
out_file,
write = True,
):
def _factory(cmd, **kw):
return _FakePopen(
cmd,
lines = lines,
returncode = returncode,
out_file = out_file,
write = write,
env = kw.get("env"),
)
monkeypatch.setattr(eng.subprocess, "Popen", _factory)
def _engine(tmp_path):
binary = tmp_path / "sd-cli"
binary.write_text("x")
return SdCppEngine(binary = str(binary))
def test_generate_success_returns_path_and_collects_logs(tmp_path, monkeypatch):
e = _engine(tmp_path)
out = tmp_path / "img.png"
_patch_popen(
monkeypatch, lines = ["loading model", "step 1/8", "done"], returncode = 0, out_file = out
)
seen: list[str] = []
files = SdCppModelFiles(diffusion_model = "/m/z.gguf", vae = "/m/ae.sft", llm = "/m/q.gguf")
params = SdCppGenParams(prompt = "a cat", steps = 8, seed = 1)
result = e.generate(files, params, output_path = str(out), on_log = seen.append)
assert result == out and out.is_file()
assert seen == ["loading model", "step 1/8", "done"]
# the real argv was built and handed to Popen
assert "--diffusion-model" in _FakePopen.captured_cmd
assert str(out) == _FakePopen.captured_cmd[_FakePopen.captured_cmd.index("--output") + 1]
# the subprocess env carries the binary's dir on the library path
var = eng._lib_path_var()
assert str(Path(e.binary).resolve().parent) in _FakePopen.captured_env.get(var, "")
def test_generate_raises_on_nonzero_exit(tmp_path, monkeypatch):
e = _engine(tmp_path)
out = tmp_path / "img.png"
_patch_popen(monkeypatch, lines = ["boom: bad gguf"], returncode = 1, out_file = out, write = False)
with pytest.raises(RuntimeError, match = "exited 1"):
e.generate(
SdCppModelFiles(diffusion_model = "/m/z.gguf"),
SdCppGenParams(prompt = "x"),
output_path = str(out),
)
def test_generate_raises_when_no_output_despite_success(tmp_path, monkeypatch):
e = _engine(tmp_path)
out = tmp_path / "img.png"
_patch_popen(monkeypatch, lines = ["ok"], returncode = 0, out_file = out, write = False)
with pytest.raises(RuntimeError, match = "no image"):
e.generate(
SdCppModelFiles(diffusion_model = "/m/z.gguf"),
SdCppGenParams(prompt = "x"),
output_path = str(out),
)
def test_generate_does_not_return_stale_preexisting_output(tmp_path, monkeypatch):
# A leftover file at the target path must not satisfy the post-run output check
# when the run itself produced nothing: the target is cleared before the run.
e = _engine(tmp_path)
out = tmp_path / "img.png"
out.write_bytes(b"stale")
_patch_popen(monkeypatch, lines = ["ok"], returncode = 0, out_file = out, write = False)
with pytest.raises(RuntimeError, match = "no image"):
e.generate(
SdCppModelFiles(diffusion_model = "/m/z.gguf"),
SdCppGenParams(prompt = "x"),
output_path = str(out),
)
assert not out.exists()
def test_generate_raises_when_binary_missing():
e = SdCppEngine(binary = None)
with pytest.raises(RuntimeError, match = "not found"):
e.generate(
SdCppModelFiles(diffusion_model = "/m/z.gguf"),
SdCppGenParams(prompt = "x"),
output_path = "/tmp/x.png",
)
class _HangingPopen:
"""A child that runs but never prints and never exits -- the case a plain
`for line in stdout` would block on forever, ignoring the timeout."""
def __init__(self, cmd, **_kw):
self._alive = True
class _Blocking:
def __init__(self, owner):
self.owner = owner
def __iter__(self):
return self
def __next__(self):
while self.owner._alive:
time.sleep(0.01)
raise StopIteration
@property
def stdout(self):
return self._Blocking(self)
def poll(self):
return None if self._alive else -9
def wait(self, timeout = None):
self._alive = False
return -9
def kill(self):
self._alive = False
def test_generate_times_out_on_silent_hang(tmp_path, monkeypatch):
e = _engine(tmp_path)
monkeypatch.setattr(eng.subprocess, "Popen", lambda cmd, **kw: _HangingPopen(cmd, **kw))
t0 = time.time()
with pytest.raises(RuntimeError, match = "timed out"):
e.generate(
SdCppModelFiles(diffusion_model = "/m/z.gguf"),
SdCppGenParams(prompt = "x"),
output_path = str(tmp_path / "x.png"),
timeout = 0.3,
)
# The timeout is enforced promptly (not blocked until stdout EOF).
assert time.time() - t0 < 5.0
def test_img2img_generate_passes_init_image(tmp_path, monkeypatch):
e = _engine(tmp_path)
out = tmp_path / "img.png"
src = tmp_path / "src.png"
src.write_bytes(b"\x89PNG\r\n")
_patch_popen(monkeypatch, lines = ["img2img"], returncode = 0, out_file = out)
e.generate(
SdCppModelFiles(diffusion_model = "/m/z.gguf"),
SdCppGenParams(prompt = "x", init_img = str(src), strength = 0.5),
output_path = str(out),
)
assert "--init-img" in _FakePopen.captured_cmd
assert str(src) == _FakePopen.captured_cmd[_FakePopen.captured_cmd.index("--init-img") + 1]
def test_generate_native_speed_dedupes_against_offload(tmp_path, monkeypatch):
e = _engine(tmp_path)
out = tmp_path / "img.png"
_patch_popen(monkeypatch, lines = ["ok"], returncode = 0, out_file = out)
# offload already adds --diffusion-fa; native_speed="default" would add it again.
e.generate(
SdCppModelFiles(diffusion_model = "/m/z.gguf"),
SdCppGenParams(prompt = "x"),
output_path = str(out),
offload = ["--offload-to-cpu", "--diffusion-fa"],
native_speed = "default",
)
# --diffusion-fa appears exactly once (de-duped), not twice.
assert _FakePopen.captured_cmd.count("--diffusion-fa") == 1
def test_generate_native_speed_adds_flag_when_not_offloaded(tmp_path, monkeypatch):
e = _engine(tmp_path)
out = tmp_path / "img.png"
_patch_popen(monkeypatch, lines = ["ok"], returncode = 0, out_file = out)
e.generate(
SdCppModelFiles(diffusion_model = "/m/z.gguf"),
SdCppGenParams(prompt = "x"),
output_path = str(out),
offload = [], # fast/resident tier: no offload, but speed flag still applies
native_speed = "default",
)
assert _FakePopen.captured_cmd.count("--diffusion-fa") == 1
def test_upscale_runs_and_returns_path(tmp_path, monkeypatch):
e = _engine(tmp_path)
out = tmp_path / "big.png"
_patch_popen(monkeypatch, lines = ["upscaling", "done"], returncode = 0, out_file = out)
result = e.upscale(
SdCppUpscaleParams(input_image = "/in/small.png", upscale_model = "/m/esrgan.pth", repeats = 2),
output_path = str(out),
)
assert result == out and out.is_file()
assert _FakePopen.captured_cmd[_FakePopen.captured_cmd.index("--mode") + 1] == "upscale"
assert "--upscale-model" in _FakePopen.captured_cmd
def test_upscale_raises_when_binary_missing(monkeypatch, tmp_path):
monkeypatch.setattr(eng, "find_sd_cpp_binary", lambda: None)
e = SdCppEngine(binary = None)
with pytest.raises(RuntimeError, match = "not found"):
e.upscale(
SdCppUpscaleParams(input_image = "/i.png", upscale_model = "/m/e.pth"),
output_path = str(tmp_path / "x.png"),
)
# ── engine routing ──────────────────────────────────────────────────────────
def test_routing_gpu_backends_use_diffusers():
for backend in ("cuda", "rocm", "xpu"):
assert select_diffusion_engine(backend, native_available = True) == ENGINE_DIFFUSERS
def test_routing_cpu_and_mps_use_native_when_available():
assert select_diffusion_engine("cpu", native_available = True) == ENGINE_SD_CPP
assert select_diffusion_engine("mps", native_available = True) == ENGINE_SD_CPP
def test_routing_cpu_falls_back_to_diffusers_without_binary():
assert select_diffusion_engine("cpu", native_available = False) == ENGINE_DIFFUSERS
def test_routing_prefer_native_overrides_gpu():
assert (
select_diffusion_engine("cuda", native_available = True, prefer_native = True) == ENGINE_SD_CPP
)
# but only if a binary is actually available
assert (
select_diffusion_engine("cuda", native_available = False, prefer_native = True)
== ENGINE_DIFFUSERS
)