🧪 test: Add unit tests for get_version fallback mechanisms

tests/unit/test_init.py

@@ -0,0 +1,131 @@
+# SPDX-FileCopyrightText: 2026 Knitli Inc.
+#
+# SPDX-License-Identifier: MIT OR Apache-2.0
+
+import importlib.metadata
+import shutil
+import subprocess
+import sys
+
+from unittest.mock import MagicMock
+
+import pytest
+
+import codeweaver
+
+
+@pytest.fixture
+def mock_no_version_file(monkeypatch):
+    """Remove _version module from sys.modules and codeweaver module.
+
+    A reload of the codeweaver module is necessary because the `get_version()`
+    function evaluates the imports (which populate its internal values) exactly once
+    at execution time. If we don't reload the module after changing sys.modules,
+    it may continue using the previously cached module references.
+    """
+    monkeypatch.delitem(sys.modules, "codeweaver._version", raising=False)
+    if hasattr(codeweaver, "_version"):
+        monkeypatch.delattr(codeweaver, "_version", raising=False)
+
+    # We must also clear the internal import mechanisms tracking caching!
+    # A cleaner approach is simply to re-import get_version explicitly so it bounds to the current env
+    import importlib
+
+    importlib.reload(codeweaver)
+    return codeweaver.get_version
+
+
+@pytest.fixture
+def mock_no_metadata(monkeypatch, mock_no_version_file):
+    """Mock importlib.metadata to raise PackageNotFoundError for code-weaver."""
+    _original_version = importlib.metadata.version
+
+    def mock_version(pkg_name):
+        if pkg_name == "code-weaver":
+            raise importlib.metadata.PackageNotFoundError("code-weaver")
+        return _original_version(pkg_name)
+
+    monkeypatch.setattr(importlib.metadata, "version", mock_version)
+    return mock_no_version_file
+
+
+def test_get_version_from_version_file(monkeypatch, mock_no_version_file):
+    """Test getting version from codeweaver._version.__version__."""
+    mock_module = MagicMock()
+    mock_module.__version__ = "1.2.3-file"
+    monkeypatch.setitem(sys.modules, "codeweaver._version", mock_module)
+
+    # Need to reload codeweaver because we just changed sys.modules
+    import importlib
+
+    importlib.reload(codeweaver)
+
+    assert codeweaver.get_version() == "1.2.3-file"
+
+
+def test_get_version_from_importlib_metadata(monkeypatch, mock_no_version_file):
+    """Test getting version from importlib.metadata."""
+    get_version = mock_no_version_file
+    _original_version = importlib.metadata.version
+
+    def mock_version(pkg_name):
+        if pkg_name == "code-weaver":
+            return "1.2.3-metadata"
+        return _original_version(pkg_name)
+
+    monkeypatch.setattr(importlib.metadata, "version", mock_version)
+
+    assert get_version() == "1.2.3-metadata"
+
+
+def test_get_version_from_git_success(monkeypatch, mock_no_metadata):
+    """Test getting version from git describe."""
+    get_version = mock_no_metadata
+    monkeypatch.setattr(shutil, "which", lambda cmd: "git" if cmd == "git" else None)
+
+    mock_result = MagicMock()
+    mock_result.returncode = 0
+    mock_result.stdout = "1.2.3-git\n"
+
+    def mock_run(*args, **kwargs):
+        return mock_result
+
+    monkeypatch.setattr(subprocess, "run", mock_run)
+
+    assert get_version() == "1.2.3-git"
+
+
+def test_get_version_from_git_failure(monkeypatch, mock_no_metadata):
+    """Test git describe fails and returns 0.0.0."""
+    get_version = mock_no_metadata
+    monkeypatch.setattr(shutil, "which", lambda cmd: "git" if cmd == "git" else None)
+
+    mock_result = MagicMock()
+    mock_result.returncode = 1
+
+    def mock_run(*args, **kwargs):
+        return mock_result
+
+    monkeypatch.setattr(subprocess, "run", mock_run)
+
+    assert get_version() == "0.0.0"
+
+
+def test_get_version_no_git(monkeypatch, mock_no_metadata):
+    """Test git is not installed, returns 0.0.0."""
+    get_version = mock_no_metadata
+    monkeypatch.setattr(shutil, "which", lambda cmd: None)
+
+    assert get_version() == "0.0.0"
+
+
+def test_get_version_exception(monkeypatch, mock_no_metadata):
+    """Test general exception in git block returns 0.0.0."""
+    get_version = mock_no_metadata
+
+    def mock_which(cmd):
+        raise RuntimeError("Something went wrong")
+
+    monkeypatch.setattr(shutil, "which", mock_which)
+
+    assert get_version() == "0.0.0"