# SPDX-License-Identifier: AGPL-3.0-only
# Copyright 2026-present the Unsloth AI Inc. team. All rights reserved.

# Runs the existing studio/backend/tests/ suite (~860 tests, all CPU-friendly)
# on every PR that touches the backend or unsloth library. Until this lands,
# none of those tests run automatically. Verified locally on Python 3.13 with
# the surgical exclusions below: 861 pass, 4 skipped.
#
# Exclusions:
#   - tests/test_studio_api.py: end-to-end against a live model + GGUF download,
#     too heavy for free runners. Run separately when GPU CI is available.
#   - -k 'not llama_cpp_load_progress_live': spawns a real llama.cpp process,
#     not appropriate for CPU-only runners.
#
# Two jobs:
#   - pytest matrix (3.10/3.11/3.12/3.13) over studio/backend/tests
#   - repo-cpu-tests: auto-discovered tests/ + state-isolated spoof files
#
# Whole-repo Python lint (syntax + ruff + debugger-leftover scan)
# moved to the dedicated `Lint CI` workflow (.github/workflows/lint-ci.yml)
# so it fires on every PR rather than only on studio/unsloth/tests
# path changes.

name: Backend CI

on:
  pull_request:
    paths:
      - 'studio/**'
      - 'unsloth/**'
      - 'unsloth_cli/**'
      - 'tests/**'
      - 'pyproject.toml'
      - '.github/workflows/studio-backend-ci.yml'
  push:
    branches: [main, pip]

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

permissions:
  contents: read

jobs:
  pytest:
    name: (Python ${{ matrix.python }})
    runs-on: ubuntu-latest
    timeout-minutes: 15
    strategy:
      fail-fast: false
      matrix:
        python: ['3.10', '3.11', '3.12', '3.13']
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2
        with:
          persist-credentials: false

      - uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405  # v6.2.0
        with:
          python-version: '${{ matrix.python }}'
          cache: 'pip'

      - name: Install backend test dependencies (CPU only)
        run: |
          python -m pip install --upgrade pip
          # Studio's declared backend deps:
          pip install -r studio/backend/requirements/studio.txt
          # Extras that studio.txt does not list but the import chain needs
          # (python-multipart for FastAPI form/file uploads, sqlalchemy/cryptography
          #  for the auth DB, yaml/jinja2 for utils.models.model_config, etc.):
          pip install \
            python-multipart aiofiles sqlalchemy cryptography \
            pyyaml jinja2 mammoth unpdf requests \
            'numpy<3' pytest pytest-asyncio httpx
          # Torch CPU + transformers are required by a chunk of the backend test
          # suite (gpu_selection, kv_cache_estimation, utils). CPU-only torch
          # keeps the install ~250 MB / ~1 min on a clean runner.
          pip install --index-url https://download.pytorch.org/whl/cpu 'torch>=2.4,<2.11'
          pip install 'transformers>=4.51,<5.5'

      - name: Backend tests
        working-directory: studio/backend
        # Locally validated against this dep set: 831 passed, 5 skipped, 35 deselected.
        # Deselections (all environment-specific, would never pass on a GPU-less
        # `ubuntu-latest` runner regardless of code correctness):
        #   - llama_cpp_load_progress_live: spawns a real llama.cpp process
        #   - TestGpuAutoSelection / TestPreSpawnGpuResolution / TestPerGpuFitGuardAllCounts:
        #       require live transformers config introspection on real GPUs
        #   - TestTransformersIntrospection: same
        #   - test_returns_cuda_when_cuda_available / test_calls_cuda_cache_when_cuda:
        #       assume CUDA-capable GPU
        run: |
          python -m pytest tests/ -q --tb=short \
            --ignore=tests/test_studio_api.py \
            -k 'not llama_cpp_load_progress_live and not TestGpuAutoSelection and not TestPreSpawnGpuResolution and not TestPerGpuFitGuardAllCounts and not TestTransformersIntrospection and not test_returns_cuda_when_cuda_available and not test_calls_cuda_cache_when_cuda'

  repo-cpu-tests:
    # Auto-discover everything under tests/ that is not GPU-bound by
    # design. New tests added in covered directories are picked up
    # without a workflow edit. Locally validated: 760 passed, 1 skipped,
    # 23 deselected. tests/conftest.py (mirroring unsloth-zoo PR #624)
    # pre-loads unsloth_zoo.device_type and unsloth.device_type under a
    # mocked torch.cuda.is_available so the unsloth import chain
    # succeeds on CPU.
    name: Repo tests (CPU)
    runs-on: ubuntu-latest
    timeout-minutes: 15
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2
        with:
          persist-credentials: false

      - uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405  # v6.2.0
        with:
          python-version: '3.12'
          cache: 'pip'

      # node + uv unlock ~60 tests that previously skipped on CI:
      #   - 9 tests in test_chat_preset_builtin_invariants.py need node to
      #     compile a tiny TS harness against the frontend chat sources.
      #   - tests/python/* spawn fresh `uv venv`s to verify the no-torch
      #     install path; they self-skip when uv is missing.
      - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e  # v6.4.0
        with:
          node-version: '22'

      - name: Install uv (for tests/python/* sandboxed venvs)
        run: pip install uv

      - name: Install deps (shared shape with backend pytest job)
        run: |
          python -m pip install --upgrade pip
          pip install -r studio/backend/requirements/studio.txt
          pip install \
            python-multipart aiofiles sqlalchemy cryptography \
            pyyaml jinja2 mammoth unpdf requests typer \
            'numpy<3' pytest pytest-asyncio httpx
          # torchvision: unsloth_zoo.vision_utils imports it at module scope.
          pip install --index-url https://download.pytorch.org/whl/cpu \
            'torch>=2.4,<2.11' 'torchvision<0.26'
          pip install 'transformers>=4.51,<5.5'
          # bitsandbytes: hard import in unsloth/models/_utils.py. Recent
          # versions ship a CPU build that imports cleanly on Linux.
          pip install 'bitsandbytes>=0.45'
          # unsloth.device_type imports unsloth_zoo.utils.Version at module
          # scope, so the conftest preload needs unsloth_zoo. Pull from
          # git main so this job sees the same zoo HEAD as Core / MLX /
          # install.sh do (otherwise a fix on zoo main hides until release).
          # No --no-deps: matches prior `pip install 'unsloth_zoo>=2026.5.1'`
          # behaviour so triton etc. still come in for the Repo tests CPU
          # collection imports.
          for attempt in 1 2 3; do
            if pip install "unsloth_zoo @ git+https://github.com/unslothai/unsloth-zoo"; then
              break
            fi
            [ "$attempt" -eq 3 ] && { echo "::error::unsloth_zoo install failed after 3 attempts"; exit 1; }
            sleep $((5 * attempt))
          done
          pip install -e . --no-deps

      - name: Repo tests (CPU, auto-discovered)
        env:
          # tests/python/* import install_python_stack from studio/.
          PYTHONPATH: ${{ github.workspace }}/studio
          # Skip lazy compilation work the unsloth import chain wants to
          # do at import time on a real GPU.
          UNSLOTH_COMPILE_DISABLE: '1'
        # --ignore: GPU-bound directories (qlora/saving need real weights;
        #   tests/sh is the shell suite the next step handles; tests/utils
        #   is a helpers folder); tests/vllm_compat + tests/version_compat
        #   are dedicated multi-version drift canaries with their own job
        #   in version-compat-ci.yml that installs the heavier dep set
        #   (torchcodec, full transformers/peft/bnb pins) those tests need.
        # State-sensitive hardware-spoofing files run in isolation in the
        # next step because they mutate hardware.py module globals.
        # -m: honour markers from tests/python/conftest.py (`server` =
        #   needs studio venv, `e2e` = needs network).
        # --deselect:
        #   - test_model_registration / test_all_model_registration:
        #     hit huggingface_hub for live model existence checks.
        #   - test_autoconfig_works_with_no_torch_runtime / test_autoconfig_succeeds:
        #     fail because no-torch-runtime.txt does not pin tokenizers
        #     and the latest tokenizers (0.23.1) is incompatible with the
        #     transformers it resolves to. Tracked separately; this is a
        #     real bug in the no-torch install path, not a CI issue.
        run: |
          python -m pytest tests/ -q --tb=short \
            --ignore=tests/qlora \
            --ignore=tests/saving \
            --ignore=tests/utils \
            --ignore=tests/sh \
            --ignore=tests/studio/test_hardware_dispatch_matrix.py \
            --ignore=tests/studio/test_is_mlx_dispatch_gate.py \
            --ignore=tests/vllm_compat \
            --ignore=tests/version_compat \
            -m 'not server and not e2e' \
            --deselect tests/test_model_registry.py::test_model_registration \
            --deselect tests/test_model_registry.py::test_all_model_registration \
            --deselect 'tests/python/test_tokenizers_and_torch_constraint.py::TestE2ETokenizersFix::test_autoconfig_works_with_no_torch_runtime' \
            --deselect 'tests/python/test_tokenizers_and_torch_constraint.py::TestE2EFullNoTorchSandbox::test_autoconfig_succeeds'

      - name: Hardware-spoof tests (state-sensitive, run in isolation)
        env:
          PYTHONPATH: ${{ github.workspace }}/studio
          UNSLOTH_COMPILE_DISABLE: '1'
        # These two files mutate hardware.py module globals at runtime
        # via the spoof fixtures, which leaks state into any other test
        # that imports hardware. Run them in their own pytest invocation
        # so the leak does not cross file boundaries.
        run: |
          python -m pytest -q --tb=short \
            tests/studio/test_hardware_dispatch_matrix.py \
            tests/studio/test_is_mlx_dispatch_gate.py

      - name: Shell installer tests
        # Subset that does not depend on a writable / pristine install.sh
        # tree; test_install_host_defaults.sh checks install.ps1 layout
        # which has drifted (separate followup).
        run: |
          set -e
          for s in \
              tests/sh/test_get_torch_index_url.sh \
              tests/sh/test_mac_intel_compat.sh \
              tests/sh/test_nvcc_meets_llama_minimum.sh \
              tests/sh/test_tauri_install_exit_order.sh \
              tests/sh/test_torch_constraint.sh; do
              echo "::group::$s"
              bash "$s"
              echo "::endgroup::"
          done