ensure packageManager is correctly set for yarn

cachi2/core/package_managers/yarn/main.py

@@ -1,8 +1,13 @@
 import logging
 
+from cachi2.core.errors import PackageRejected
 from cachi2.core.models.input import Request
 from cachi2.core.models.output import Component, EnvironmentVariable, RequestOutput
-from cachi2.core.package_managers.yarn.project import Project
+from cachi2.core.package_managers.yarn.project import (
+    Project,
+    get_semver_from_package_manager,
+    get_semver_from_yarn_path,
+)
 from cachi2.core.package_managers.yarn.resolver import (
     create_component_from_package,
     resolve_packages,
@@ -52,10 +57,41 @@ def _resolve_yarn_project(project: Project, output_dir: RootedPath) -> list[Comp
 def _configure_yarn_version(project: Project) -> None:
     """Resolve the yarn version and set it in the package.json file if needed.
 
-    :raises PackageRejected: in case the yarn version can't be determined, or if there is a
-        mismatch between the version in package.json and yarnrc.yml.
+    :raises PackageRejected:
+        if the yarn version can't be determined from either yarnPath or packageManager
+        if there is a mismatch between the yarn version specified by yarnPath and PackageManager
     """
-    pass
+    yarn_path_version = get_semver_from_yarn_path(project.yarn_rc.yarn_path)
+    package_manager_version = get_semver_from_package_manager(project.package_json.package_manager)
+
+    if not yarn_path_version and not package_manager_version:
+        raise PackageRejected(
+            "Unable to determine the yarn version to use to process the request",
+            solution=(
+                "Ensure that either yarnPath is defined in .yarnrc.yml or that packageManager "
+                "is defined in package.json"
+            ),
+        )
+
+    if (
+        yarn_path_version
+        and package_manager_version
+        and yarn_path_version != package_manager_version
+    ):
+        raise PackageRejected(
+            (
+                f"Mismatch between the yarn versions specified by yarnPath (yarn@{yarn_path_version}) "
+                f"and packageManager (yarn@{package_manager_version})"
+            ),
+            solution=(
+                "Ensure that the versions of yarn specified by yarnPath in .yarnrc.yml and "
+                "packageManager in package.json agree"
+            ),
+        )
+
+    if not package_manager_version:
+        project.package_json.package_manager = f"yarn@{yarn_path_version}"
+        project.package_json.write_to_file()
 
 
 def _set_yarnrc_configuration(project: Project, output_dir: RootedPath) -> None:

cachi2/core/package_managers/yarn/project.py

@@ -4,10 +4,19 @@
 It also provides basic utility functions. The main logic to resolve and prefetch the dependencies
 should be implemented in other modules.
 """
+import json
+import logging
+import re
+from pathlib import Path
 from typing import Any, NamedTuple, Optional
 
+import semver
+
+from cachi2.core.errors import UnexpectedFormat
 from cachi2.core.rooted_path import RootedPath
 
+log = logging.getLogger(__name__)
+
 
 class YarnRc:
     """A yarnrc file.
@@ -91,11 +100,22 @@ def package_manager(self) -> Optional[str]:
         """Get the package manager string."""
         return NotImplemented
 
+    @package_manager.setter
+    def package_manager(self, package_manager: str) -> None:
+        """Set the package manager string."""
+        self._data["packageManager"] = package_manager
+
     @classmethod
     def from_file(cls, file_path: RootedPath) -> "PackageJson":
         """Parse the content of a package.json file."""
         return NotImplemented
 
+    def write_to_file(self) -> None:
+        """Write the data to the package.json file."""
+        with self._path.path.open("w") as f:
+            json.dump(self._data, f, indent=2)
+            f.write("\n")
+
 
 class Project(NamedTuple):
     """A directory containing yarn sources."""
@@ -126,3 +146,69 @@ def yarn_cache(self) -> RootedPath:
     def from_source_dir(cls, source_dir: RootedPath) -> "Project":
         """Create a Project from a sources directory path."""
         return cls(source_dir, NotImplemented, NotImplemented)
+
+
+def get_semver_from_yarn_path(yarn_path: Optional[str]) -> Optional[semver.version.Version]:
+    """Parse yarnPath from yarnrc and return a semver Version if possible else None."""
+    if not yarn_path:
+        return None
+
+    # https://github.com/yarnpkg/berry/blob/2dc59443e541098bc0104d97b5fc452781c64baf/packages/plugin-essentials/sources/commands/set/version.ts#L208
+    yarn_spec_pattern = re.compile(r"^yarn-(.+)\.cjs$")
+    match = yarn_spec_pattern.match(Path(yarn_path).name)
+    if not match:
+        log.warning(
+            (
+                "The yarn version specified by yarnPath in .yarnrc.yml (%s) does not match the "
+                "expected format yarn-<semver>.cjs. Attempting to use the version specified by "
+                "packageManager in package.json."
+            ),
+            yarn_path,
+        )
+        return None
+
+    yarn_version = match.group(1)
+    try:
+        return semver.version.Version.parse(yarn_version)
+    except ValueError:
+        log.warning(
+            (
+                "The yarn version specified by yarnPath in .yarnrc.yml (%s) is not a valid semver. "
+                "Attempting to use the version specified by packageManager in package.json."
+            ),
+            yarn_path,
+        )
+        return None
+
+
+def get_semver_from_package_manager(
+    package_manager: Optional[str],
+) -> Optional[semver.version.Version]:
+    """Parse packageManager from package.json and return a semver Version if possible.
+
+    :raises UnexpectedFormat:
+        if packageManager doesn't match the name@semver format
+        if packageManager does not specify yarn
+        if packageManager version is not a valid semver
+    """
+    if not package_manager:
+        return None
+
+    # https://github.com/nodejs/corepack/blob/787e24df609513702eafcd8c6a5f03544d7d45cc/sources/specUtils.ts#L10
+    package_manager_spec_pattern = re.compile(r"^(?!_)(.+)@(.+)$")
+    match = package_manager_spec_pattern.match(package_manager)
+    if not match:
+        raise UnexpectedFormat(
+            "could not parse packageManager spec in package.json (expected name@semver)"
+        )
+
+    name, version = match.groups()
+    if name != "yarn":
+        raise UnexpectedFormat("packageManager in package.json must be yarn")
+
+    try:
+        return semver.version.Version.parse(version)
+    except ValueError as e:
+        raise UnexpectedFormat(
+            f"{version} is not a valid semver for packageManager in package.json"
+        ) from e

tests/unit/package_managers/yarn/test_main.py

@@ -1,12 +1,103 @@
+import re
+from typing import Optional, Union
 from unittest import mock
 
 import pytest
+import semver
 
-from cachi2.core.errors import YarnCommandError
-from cachi2.core.package_managers.yarn.main import _fetch_dependencies
+from cachi2.core.errors import PackageRejected, UnexpectedFormat, YarnCommandError
+from cachi2.core.package_managers.yarn.main import _configure_yarn_version, _fetch_dependencies
 from cachi2.core.rooted_path import RootedPath
 
 
+@pytest.mark.parametrize(
+    "yarn_path_version, package_manager_version",
+    [
+        pytest.param(semver.VersionInfo(1, 0, 0), None, id="valid-yarnpath-no-packagemanager"),
+        pytest.param(None, semver.VersionInfo(1, 0, 0), id="no-yarnpath-valid-packagemanager"),
+        pytest.param(
+            semver.VersionInfo(1, 0, 0),
+            semver.VersionInfo(1, 0, 0),
+            id="matching-yarnpath-and-packagemanager",
+        ),
+        pytest.param(
+            semver.VersionInfo(1, 0, 0),
+            semver.VersionInfo(
+                1, 0, 0, build="sha224.953c8233f7a92884eee2de69a1b92d1f2ec1655e66d08071ba9a02fa"
+            ),
+            id="matching-yarnpath-and-packagemanager-with-build",
+        ),
+    ],
+)
+@mock.patch("cachi2.core.package_managers.yarn.main.get_semver_from_package_manager")
+@mock.patch("cachi2.core.package_managers.yarn.main.get_semver_from_yarn_path")
+def test_configure_yarn_version(
+    mock_yarn_path_semver: mock.Mock,
+    mock_package_manager_semver: mock.Mock,
+    yarn_path_version: Optional[semver.version.Version],
+    package_manager_version: Optional[semver.version.Version],
+) -> None:
+    mock_project = mock.Mock()
+    mock_project.package_json.package_manager = None
+    mock_yarn_path_semver.return_value = yarn_path_version
+    mock_package_manager_semver.return_value = package_manager_version
+
+    _configure_yarn_version(mock_project)
+
+    if package_manager_version is None:
+        assert mock_project.package_json.package_manager == f"yarn@{yarn_path_version}"
+        mock_project.package_json.write_to_file.assert_called_once()
+    else:
+        assert mock_project.package_json.package_manager is None
+        mock_project.package_json.write_to_file.assert_not_called()
+
+
+@pytest.mark.parametrize(
+    "yarn_path_version, package_manager_version, expected_error",
+    [
+        pytest.param(
+            None,
+            None,
+            PackageRejected(
+                "Unable to determine the yarn version to use to process the request",
+                solution="Ensure that either yarnPath is defined in .yarnrc or that packageManager is defined in package.json",
+            ),
+            id="no-yarnpath-no-packagemanager",
+        ),
+        pytest.param(
+            None,
+            UnexpectedFormat("some error about packageManager formatting"),
+            UnexpectedFormat("some error about packageManager formatting"),
+            id="exception-parsing-packagemanager",
+        ),
+        pytest.param(
+            semver.VersionInfo(1, 0, 1),
+            semver.VersionInfo(1, 0, 0),
+            PackageRejected(
+                "Mismatch between the yarn versions specified by yarnPath ([email protected]) and packageManager ([email protected])",
+                solution="Ensure that the yarnPath version in .yarnrc and the packageManager version in package.json agree",
+            ),
+            id="yarnpath-packagemanager-mismatch",
+        ),
+    ],
+)
+@mock.patch("cachi2.core.package_managers.yarn.main.get_semver_from_package_manager")
+@mock.patch("cachi2.core.package_managers.yarn.main.get_semver_from_yarn_path")
+def test_configure_yarn_version_fail(
+    mock_yarn_path_semver: mock.Mock,
+    mock_package_manager_semver: mock.Mock,
+    yarn_path_version: Optional[semver.version.Version],
+    package_manager_version: Union[semver.version.Version, None, Exception],
+    expected_error: Exception,
+) -> None:
+    mock_project = mock.Mock()
+    mock_yarn_path_semver.return_value = yarn_path_version
+    mock_package_manager_semver.side_effect = [package_manager_version]
+
+    with pytest.raises(type(expected_error), match=re.escape(str(expected_error))):
+        _configure_yarn_version(mock_project)
+
+
 @mock.patch("cachi2.core.package_managers.yarn.main.run_yarn_cmd")
 def test_fetch_dependencies(mock_yarn_cmd: mock.Mock, rooted_tmp_path: RootedPath) -> None:
     source_dir = rooted_tmp_path