Add tests for sync tool

Author: CoolCat467

src/trio/_tests/tools/test_sync_requirements.py

@@ -0,0 +1,82 @@
+from __future__ import annotations
+
+from pathlib import Path
+from typing import TYPE_CHECKING
+
+from trio._tests.pytest_plugin import skip_if_optional_else_raise
+
+# imports in gen_exports that are not in `install_requires` in requirements
+try:
+    import yaml  # noqa: F401
+except ImportError as error:
+    skip_if_optional_else_raise(error)
+
+from trio._tools.sync_requirements import (
+    update_requirements,
+    yield_pre_commit_version_data,
+)
+
+if TYPE_CHECKING:
+    from pathlib import Path
+
+
+def test_yield_pre_commit_version_data() -> None:
+    text = """
+repos:
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.11.0
+  - repo: https://github.com/psf/black-pre-commit-mirror
+    rev: 25.1.0
+"""
+    results = tuple(yield_pre_commit_version_data(text))
+    assert results == (
+        ("ruff-pre-commit", "0.11.0"),
+        ("black-pre-commit-mirror", "25.1.0"),
+    )
+
+
+def test_update_requirements(
+    tmp_path: Path,
+) -> None:
+    requirements_file = tmp_path / "requirements.txt"
+    assert not requirements_file.exists()
+    requirements_file.write_text(
+        """# comment
+  # also comment but spaces line start
+waffles are delicious no equals
+black==3.1.4 ; specific version thingy
+mypy==1.15.0
+ruff==1.2.5
+# required by soupy cat""",
+        encoding="utf-8",
+    )
+    assert update_requirements(requirements_file, {"black": "3.1.5", "ruff": "1.2.7"})
+    assert (
+        requirements_file.read_text(encoding="utf-8")
+        == """# comment
+  # also comment but spaces line start
+waffles are delicious no equals
+black==3.1.5 ; specific version thingy
+mypy==1.15.0
+ruff==1.2.7
+# required by soupy cat"""
+    )
+
+
+def test_update_requirements_no_changes(
+    tmp_path: Path,
+) -> None:
+    requirements_file = tmp_path / "requirements.txt"
+    assert not requirements_file.exists()
+    original = """# comment
+  # also comment but spaces line start
+waffles are delicious no equals
+black==3.1.4 ; specific version thingy
+mypy==1.15.0
+ruff==1.2.5
+# required by soupy cat"""
+    requirements_file.write_text(original, encoding="utf-8")
+    assert not update_requirements(
+        requirements_file, {"black": "3.1.4", "ruff": "1.2.5"}
+    )
+    assert requirements_file.read_text(encoding="utf-8") == original

src/trio/_tools/sync_requirements.py

@@ -25,10 +25,10 @@
 
 
 def yield_pre_commit_version_data(
-    pre_commit: Path,
+    pre_commit_text: str,
 ) -> Generator[tuple[str, str], None, None]:
     """Yield (name, rev) tuples from pre-commit config file."""
-    pre_commit_config = load_yaml(pre_commit.read_text(encoding="utf-8"), Loader)
+    pre_commit_config = load_yaml(pre_commit_text, Loader)
     for repo in pre_commit_config["repos"]:
         if "repo" not in repo or "rev" not in repo:
             continue
@@ -81,18 +81,19 @@ def main() -> int:
     """Run program."""
 
     source_root = Path.cwd().absolute()
-    while not (source_root / "LICENSE").exists():
-        source_root = source_root.parent
+
     # Double-check we found the right directory
     assert (source_root / "LICENSE").exists()
     pre_commit = source_root / ".pre-commit-config.yaml"
     test_requirements = source_root / "test-requirements.txt"
 
+    pre_commit_text = pre_commit.read_text(encoding="utf-8")
+
     # Get tool versions from pre-commit
     # Get correct names
     pre_commit_versions = {
         name.removesuffix("-mirror").removesuffix("-pre-commit"): version
-        for name, version in yield_pre_commit_version_data(pre_commit)
+        for name, version in yield_pre_commit_version_data(pre_commit_text)
     }
     changed = update_requirements(test_requirements, pre_commit_versions)
     return int(changed)