add tests - part 1

.coveragerc

@@ -0,0 +1,7 @@
+[run]
+branch = True
+source = scmrepo
+
+[report]
+exclude_lines =
+    if TYPE_CHECKING:

.github/workflows/tests.yaml

@@ -2,9 +2,10 @@ name: Tests
 on: push
 jobs:
   tests:
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
     strategy:
       matrix:
+        os: [ubuntu-20.04, windows-latest, macos-latest]
         python-version: ['3.7', '3.8', '3.9', '3.10']
     name: Python ${{ matrix.python-version }}
     steps:

pyproject.toml

@@ -25,6 +25,11 @@ profile = "black"
 known_first_party = ["scmrepo"]
 line_length = 79
 
+[tool.pytest.ini_options]
+markers = [
+    "skip_git_backend: skip tests for given backend",
+]
+
 [tool.mypy]
 # Error output
 show_column_numbers = true
@@ -37,7 +42,7 @@ check_untyped_defs = false
 warn_no_return = true
 warn_redundant_casts = true
 warn_unreachable = true
-files = ["scmrepo"]
+files = ["scmrepo", "tests"]
 
 [[tool.mypy.overrides]]
 module = [
@@ -59,7 +64,7 @@ extension-pkg-whitelist = ["pygit2"]
 disable = [
     "format", "refactoring", "design", "no-self-use", "invalid-name", "duplicate-code",
     "missing-function-docstring", "missing-module-docstring", "missing-class-docstring",
-    "raise-missing-from", "import-outside-toplevel", "cyclic-import"
+    "raise-missing-from", "import-outside-toplevel", "cyclic-import", "fixme",
 ]
 enable = ["c-extension-no-member", "no-else-return"]
 

scmrepo/git/__init__.py

@@ -6,7 +6,7 @@
 from collections.abc import Mapping
 from contextlib import contextmanager
 from functools import partialmethod
-from typing import Dict, Iterable, Optional, Tuple, Type
+from typing import Dict, Iterable, Optional, Tuple, Type, Union
 
 from funcy import cached_property, first
 from pathspec.patterns import GitWildMatchPattern
@@ -260,6 +260,29 @@ def get_fs(self, rev: str):
 
         return GitFileSystem(scm=self, rev=rev)
 
+    @classmethod
+    def init(
+        cls, path: str, bare: bool = False, _backend: str = None
+    ) -> "Git":
+        for name, backend in GitBackends.DEFAULT.items():
+            if _backend and name != _backend:
+                continue
+            try:
+                backend.init(path, bare=bare)
+                # TODO: reuse created object instead of initializing a new one.
+                return cls(path)
+            except NotImplementedError:
+                pass
+        raise NoGitBackendError("init")
+
+    def add_commit(
+        self,
+        paths: Union[str, Iterable[str]],
+        message: str,
+    ) -> None:
+        self.add(paths)
+        self.commit(msg=message)
+
     is_ignored = partialmethod(_backend_func, "is_ignored")
     add = partialmethod(_backend_func, "add")
     commit = partialmethod(_backend_func, "commit")

scmrepo/git/backend/base.py

@@ -55,6 +55,11 @@ def clone(
     ):
         pass
 
+    @staticmethod
+    @abstractmethod
+    def init(path: str, bare: bool = False) -> None:
+        pass
+
     @property
     @abstractmethod
     def dir(self) -> str:

scmrepo/git/backend/dulwich/__init__.py

@@ -139,6 +139,12 @@ def clone(
     ):
         raise NotImplementedError
 
+    @staticmethod
+    def init(path: str, bare: bool = False) -> None:
+        from dulwich.porcelain import init
+
+        init(path, bare=bare)
+
     @property
     def dir(self) -> str:
         return self.repo.commondir()

scmrepo/git/backend/gitpython.py

@@ -202,6 +202,21 @@ def clone(
                     )
                 ) from exc
 
+    @staticmethod
+    def init(path: str, bare: bool = False) -> None:
+        from funcy import retry
+        from git import Repo
+        from git.exc import GitCommandNotFound
+
+        # NOTE: handles EAGAIN error on BSD systems (osx in our case).
+        # Otherwise when running tests you might get this exception:
+        #
+        #    GitCommandNotFound: Cmd('git') not found due to:
+        #        OSError('[Errno 35] Resource temporarily unavailable')
+        method = retry(5, GitCommandNotFound)(Repo.init)
+        git = method(path, bare=bare)
+        git.close()
+
     @staticmethod
     def is_sha(rev):
         import git

scmrepo/git/backend/pygit2.py

@@ -156,6 +156,12 @@ def clone(
     ):
         raise NotImplementedError
 
+    @staticmethod
+    def init(path: str, bare: bool = False) -> None:
+        from pygit2 import init_repository
+
+        init_repository(path, bare=bare)
+
     @property
     def dir(self) -> str:
         raise NotImplementedError

setup.cfg

@@ -37,11 +37,19 @@ install_requires=
 dev =
     pytest==6.2.5
     pytest-sugar==0.9.4
+    pytest-test-utils==0.0.5
+    pytest-cov==3.0.0
+    pytest-mock==3.6.1
     pylint==2.11.1
     mypy==0.910
     types-certifi==2021.10.8.0
     types-paramiko==2.8.1
 
+[options.packages.find]
+exclude =
+    tests
+    tests.*
+
 [flake8]
 ignore=
     E203, # Whitespace before ':'

tests/conftest.py

@@ -0,0 +1,46 @@
+import os
+import sys
+
+import pygit2
+import pytest
+from pytest_test_utils import TempDirFactory, TmpDir
+
+from scmrepo.git import Git
+
+
+@pytest.fixture(autouse=True)
+def isolate(tmp_dir_factory: TempDirFactory, monkeypatch: pytest.MonkeyPatch):
+    path = tmp_dir_factory.mktemp("mock")
+    home_dir = path / "home"
+    home_dir.mkdir()
+
+    if sys.platform == "win32":
+        home_drive, home_path = os.path.splitdrive(home_dir)
+        monkeypatch.setenv("USERPROFILE", str(home_dir))
+        monkeypatch.setenv("HOMEDRIVE", home_drive)
+        monkeypatch.setenv("HOMEPATH", home_path)
+    else:
+        monkeypatch.setenv("HOME", str(home_dir))
+
+    monkeypatch.setenv("GIT_CONFIG_NOSYSTEM", "1")
+    contents = b"""
+[user]
+name=DVC Tester
+email=dvctester@example.com
+[init]
+defaultBranch=master
+"""
+    (home_dir / ".gitconfig").write_bytes(contents)
+    pygit2.settings.search_path[pygit2.GIT_CONFIG_LEVEL_GLOBAL] = str(home_dir)
+
+
+@pytest.fixture
+def scm(tmp_dir: TmpDir):
+    git_ = Git.init(tmp_dir)
+    sig = git_.pygit2.default_signature
+
+    assert sig.email == "dvctester@example.com"
+    assert sig.name == "DVC Tester"
+
+    yield git_
+    git_.close()

tests/test_dulwich.py

@@ -0,0 +1,28 @@
+import pytest
+from pytest_mock import MockerFixture
+
+
+@pytest.mark.parametrize(
+    "algorithm", [b"ssh-rsa", b"rsa-sha2-256", b"rsa-sha2-512"]
+)
+def test_dulwich_github_compat(mocker: MockerFixture, algorithm: bytes):
+    from asyncssh.misc import ProtocolError
+
+    from scmrepo.git.backend.dulwich.asyncssh_vendor import (
+        _process_public_key_ok_gh,
+    )
+
+    key_data = b"foo"
+    auth = mocker.Mock(
+        _keypair=mocker.Mock(algorithm=algorithm, public_data=key_data),
+    )
+    packet = mocker.Mock()
+
+    with pytest.raises(ProtocolError):
+        strings = iter((b"ed21556", key_data))
+        packet.get_string = lambda: next(strings)
+        _process_public_key_ok_gh(auth, None, None, packet)
+
+    strings = iter((b"ssh-rsa", key_data))
+    packet.get_string = lambda: next(strings)
+    _process_public_key_ok_gh(auth, None, None, packet)