tests: Add example project for offline builds

tests/conftest.py

@@ -0,0 +1,57 @@
+import shutil
+import sys
+from pathlib import Path
+
+import pytest
+
+from helpers import chdir, check_run
+
+
+if sys.version_info >= (3, 9):
+    removesuffix = str.removesuffix
+else:
+    def removesuffix(s: str, suffix: str) -> str:
+        if not s.endswith(suffix):
+            return s
+        return s[:-len(suffix)]
+
+
+def _src_name(src):
+    if isinstance(src, Path):
+        return src.name
+
+    return removesuffix(src, '.git').rsplit('/', 1)[1]
+
+
+# pylint: disable=redefined-outer-name
+# would trigger on any fixture which uses another fixture defined in the same file
+
+@pytest.fixture(scope="session", ids=_src_name, params=(
+    Path(__file__).parent / 'fixtures' / 'minimal-package',
+    Path(__file__).parent.parent,  # bork's source tree
+    ) + tuple(pytest.param(url, marks=pytest.mark.network) for url in (
+    "https://github.com/astronouth7303/ppb-mutant.git",
+    "https://github.com/duckinator/emanate.git",
+    "https://github.com/ppb/ppb-vector.git",
+)))
+def project_src(request, tmp_path_factory):
+    """Provide a source tree, which is cached over the whole pytest run.
+
+    This fixture is parameterized over all the source trees that are built during tests,
+    making any test (or fixture) that uses it parameterized itself.
+    """
+    if isinstance(request.param, Path):
+        return request.param
+
+    url = request.param
+    dest = tmp_path_factory.mktemp(_src_name(url))
+    check_run(['git', 'clone', '--depth', '1', url, dest])
+    return dest
+
+
+@pytest.fixture(scope="function")
+def project(project_src, tmp_path):
+    """Provide a fresh copy of a source tree, which is discarded after the current test."""
+    shutil.copytree(project_src, tmp_path, dirs_exist_ok=True)
+    with chdir(tmp_path):
+        yield tmp_path

tests/fixtures/minimal-package/pyproject.toml

@@ -0,0 +1,8 @@
+[build-system]
+# Specify the required build system.
+requires = ["setuptools >= 61", "wheel"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "test-project-please-ignore"
+version = "0"

tests/fixtures/minimal-package/src/__init__.py

@@ -0,0 +1,2 @@
+"""Test module, please ignore.  🥺
+"""

tests/helpers.py

@@ -1,8 +1,10 @@
+import os
 import subprocess
 import sys
 import tarfile
 import zipfile
-
+from contextlib import contextmanager
+from pathlib import Path
 
 def check_tgz(path):
     assert tarfile.is_tarfile(path)
@@ -37,3 +39,12 @@ def python_check(*args):
 
 def bork_check(*args):
     return python_check("-m", "bork", *args)
+
+
+@contextmanager
+def chdir(path):
+    cwd = Path.cwd()
+
+    os.chdir(path)
+    yield
+    os.chdir(cwd)

tests/test_cmd_download.py

@@ -1,33 +1,30 @@
-import os
-
 import pytest
-from helpers import bork_check, python_check, check_zipfile, check_tgz
+from helpers import chdir, bork_check, python_check, check_zipfile, check_tgz
 
 
 @pytest.mark.network
 def test_download(tmpdir):
-    os.chdir(tmpdir)
-
-    # Download a pyz file from GitHub, saved to ./downloads, and check
-    # that it can be run with Python.
-    bork_check("download", "gh:duckinator/emanate", "v7.0.0")
-    python_check("downloads/emanate-7.0.0.pyz", "--help")
-
-    # Download a pyz file for a specific version from GitHub, saved to ./bin
-    bork_check("download", "gh:duckinator/emanate", "v7.0.0", "--directory", "bin/")
-    python_check("bin/emanate-7.0.0.pyz", "--help")
-
-    # Download a .tar.gz file from GitHub, saved to ./downloads
-    bork_check("download",
-               "gh:ppb/pursuedpybear", "v0.6.0",
-               "--files", "*.tar.gz",
-               "--directory", "downloads")
-    assert check_tgz("downloads/ppb-0.6.0.tar.gz")
-
-    # Download a .whl file from PyPi, and verify it's uncorrupted.
-    bork_check("download", "pypi:emanate", "v6.0.0", "--files", "*.whl")
-    assert check_zipfile("downloads/emanate-6.0.0-py3-none-any.whl")
-
-    # Download a .whl file from PyPi's test instance, and verify it's uncorrupted.
-    bork_check("download", "pypi-test:whaledo", "1.0.1", "--files", "*.whl")
-    assert check_zipfile("downloads/whaledo-1.0.1-py3-none-any.whl")
+    with chdir(tmpdir):
+        # Download a pyz file from GitHub, saved to ./downloads, and check
+        # that it can be run with Python.
+        bork_check("download", "gh:duckinator/emanate", "v7.0.0")
+        python_check("downloads/emanate-7.0.0.pyz", "--help")
+
+        # Download a pyz file for a specific version from GitHub, saved to ./bin
+        bork_check("download", "gh:duckinator/emanate", "v7.0.0", "--directory", "bin/")
+        python_check("bin/emanate-7.0.0.pyz", "--help")
+
+        # Download a .tar.gz file from GitHub, saved to ./downloads
+        bork_check("download",
+                   "gh:ppb/pursuedpybear", "v0.6.0",
+                   "--files", "*.tar.gz",
+                   "--directory", "downloads")
+        assert check_tgz("downloads/ppb-0.6.0.tar.gz")
+
+        # Download a .whl file from PyPi, and verify it's uncorrupted.
+        bork_check("download", "pypi:emanate", "v6.0.0", "--files", "*.whl")
+        assert check_zipfile("downloads/emanate-6.0.0-py3-none-any.whl")
+
+        # Download a .whl file from PyPi's test instance, and verify it's uncorrupted.
+        bork_check("download", "pypi-test:whaledo", "1.0.1", "--files", "*.whl")
+        assert check_zipfile("downloads/whaledo-1.0.1-py3-none-any.whl")

tests/test_repos.py

@@ -1,38 +1,11 @@
-import os
-from pathlib import Path
-
 import pytest
-from helpers import bork_check, check_run
+from helpers import bork_check
 
+# pylint: disable=unused-argument
+# the `project` feature is used implicitly, as it changes the working directory
 
-def _repo_test(tmpdir, repo):
-    os.chdir(tmpdir)
-    check_run(['git', 'clone', '--depth', '1', repo, str(Path(tmpdir, 'repo'))])
-    os.chdir('repo')
+@pytest.mark.slow
+def test_repo(project):
     bork_check('clean')
     bork_check('build')
     bork_check('release', '--dry-run')
-
-
-@pytest.mark.network
-@pytest.mark.slow
-def test_repo_ppb_vector(tmpdir):
-    _repo_test(tmpdir, 'https://github.com/ppb/ppb-vector.git')
-
-
-@pytest.mark.network
-@pytest.mark.slow
-def test_repo_emanate(tmpdir):
-    _repo_test(tmpdir, 'https://github.com/duckinator/emanate.git')
-
-
-@pytest.mark.network
-@pytest.mark.slow
-def test_repo_bork(tmpdir):
-    _repo_test(tmpdir, 'https://github.com/duckinator/bork.git')
-
-
-@pytest.mark.network
-@pytest.mark.slow
-def test_repo_ppb_mutant(tmpdir):
-    _repo_test(tmpdir, 'https://github.com/astronouth7303/ppb-mutant.git')