Adapt .python-version requirements to connect accepted ones

.vscode/settings.json

@@ -24,4 +24,7 @@
         "build/**": true,
         "venv/**": true,
     },
+    "python.analysis.exclude": [
+        "tests"
+    ],
 }

rsconnect/pyproject.py

@@ -5,16 +5,23 @@
 but not from setup.py due to its dynamic nature.
 """
 
+import configparser
 import pathlib
+import re
 import typing
-import configparser
 
 try:
     import tomllib
 except ImportError:
     # Python 3.11+ has tomllib in the standard library
     import toml as tomllib  # type: ignore[no-redef]
 
+from .log import logger
+
+
+PEP440_OPERATORS_REGEX = r"(===|==|!=|<=|>=|<|>|~=)"
+VALID_VERSION_REQ_REGEX = rf"^({PEP440_OPERATORS_REGEX}?\d+(\.[\d\*]+)*)+$"
+
 
 def detect_python_version_requirement(directory: typing.Union[str, pathlib.Path]) -> typing.Optional[str]:
     """Detect the python version requirement for a project.
@@ -26,7 +33,12 @@ def detect_python_version_requirement(directory: typing.Union[str, pathlib.Path]
     """
     for _, metadata_file in lookup_metadata_file(directory):
         parser = get_python_version_requirement_parser(metadata_file)
-        version_constraint = parser(metadata_file)
+        try:
+            version_constraint = parser(metadata_file)
+        except InvalidVersionConstraintError as err:
+            logger.error(f"Invalid python version constraint in {metadata_file}, ignoring it: {err}")
+            continue
+
         if version_constraint:
             return version_constraint
 
@@ -103,5 +115,44 @@ def parse_pyversion_python_requires(pyversion_file: pathlib.Path) -> typing.Opti
 
     Returns None if the field is not found.
     """
-    content = pyversion_file.read_text()
-    return content.strip()
+    return adapt_python_requires(pyversion_file.read_text().strip())
+
+
+def adapt_python_requires(
+    python_requires: str,
+) -> str:
+    """Convert a literal python version to a PEP440 constraint.
+
+    Connect expects a PEP440 format, but the .python-version file can contain
+    plain version numbers and other formats.
+
+    We should convert them to the constraints that connect expects.
+    """
+    current_contraints = python_requires.split(",")
+
+    def _adapt_contraint(constraints: typing.List[str]) -> typing.Generator[str, None, None]:
+        for constraint in constraints:
+            constraint = constraint.strip()
+            if "@" in constraint or "-" in constraint or "/" in constraint:
+                raise InvalidVersionConstraintError(f"python specific implementations are not supported: {constraint}")
+
+            if "b" in constraint or "rc" in constraint or "a" in constraint:
+                raise InvalidVersionConstraintError(f"pre-release versions are not supported: {constraint}")
+
+            if re.match(VALID_VERSION_REQ_REGEX, constraint) is None:
+                raise InvalidVersionConstraintError(f"Invalid python version: {constraint}")
+
+            if re.search(PEP440_OPERATORS_REGEX, constraint):
+                yield constraint
+            else:
+                # Convert to PEP440 format
+                if "*" in constraint:
+                    yield f"=={constraint}"
+                else:
+                    yield f"~={constraint.rstrip('0').rstrip('.')}"  # Remove trailing zeros and dots
+
+    return ",".join(_adapt_contraint(current_contraints))
+
+
+class InvalidVersionConstraintError(ValueError):
+    pass

tests/test_environment.py

@@ -143,12 +143,12 @@ def test_pyproject_toml(self):
     def test_python_version(self):
         env = Environment.create_python_environment(os.path.join(TESTDATA, "python-project", "using_pyversion"))
         assert env.python_interpreter == sys.executable
-        assert env.python_version_requirement == ">=3.8, <3.12"
+        assert env.python_version_requirement == ">=3.8,<3.12"
 
     def test_all_of_them(self):
         env = Environment.create_python_environment(os.path.join(TESTDATA, "python-project", "allofthem"))
         assert env.python_interpreter == sys.executable
-        assert env.python_version_requirement == ">=3.8, <3.12"
+        assert env.python_version_requirement == ">=3.8,<3.12"
 
     def test_missing(self):
         env = Environment.create_python_environment(os.path.join(TESTDATA, "python-project", "empty"))

tests/test_pyproject.py

@@ -1,17 +1,19 @@
 import os
 import pathlib
+import tempfile
+
+import pytest
 
 from rsconnect.pyproject import (
+    detect_python_version_requirement,
+    get_python_version_requirement_parser,
     lookup_metadata_file,
     parse_pyproject_python_requires,
-    parse_setupcfg_python_requires,
     parse_pyversion_python_requires,
-    get_python_version_requirement_parser,
-    detect_python_version_requirement,
+    parse_setupcfg_python_requires,
+    InvalidVersionConstraintError,
 )
 
-import pytest
-
 HERE = os.path.dirname(__file__)
 PROJECTS_DIRECTORY = os.path.abspath(os.path.join(HERE, "testdata", "python-project"))
 
@@ -117,7 +119,7 @@ def test_setupcfg_python_requires(project_dir, expected):
 @pytest.mark.parametrize(
     "project_dir, expected",
     [
-        (os.path.join(PROJECTS_DIRECTORY, "using_pyversion"), ">=3.8, <3.12"),
+        (os.path.join(PROJECTS_DIRECTORY, "using_pyversion"), ">=3.8,<3.12"),
     ],
     ids=["option-exists"],
 )
@@ -139,6 +141,60 @@ def test_detect_python_version_requirement():
     version requirement is used.
     """
     project_dir = os.path.join(PROJECTS_DIRECTORY, "allofthem")
-    assert detect_python_version_requirement(project_dir) == ">=3.8, <3.12"
+    assert detect_python_version_requirement(project_dir) == ">=3.8,<3.12"
 
     assert detect_python_version_requirement(os.path.join(PROJECTS_DIRECTORY, "empty")) is None
+
+
+@pytest.mark.parametrize(  # type: ignore
+    ["content", "expected"],
+    [
+        ("3.8", "~=3.8"),
+        ("3.8.0", "~=3.8"),
+        ("3.8.0b1", InvalidVersionConstraintError("pre-release versions are not supported: 3.8.0b1")),
+        ("3.8.0rc1", InvalidVersionConstraintError("pre-release versions are not supported: 3.8.0rc1")),
+        ("3.8.0a1", InvalidVersionConstraintError("pre-release versions are not supported: 3.8.0a1")),
+        ("3.8.*", "==3.8.*"),
+        ("3.*", "==3.*"),
+        ("*", InvalidVersionConstraintError("Invalid python version: *")),
+        # This is not perfect, but the added regex complexity doesn't seem worth it.
+        ("invalid", InvalidVersionConstraintError("pre-release versions are not supported: invalid")),
+        ("[email protected]", InvalidVersionConstraintError("python specific implementations are not supported: [email protected]")),
+        (
+            "cpython-3.12.3-macos-aarch64-none",
+            InvalidVersionConstraintError(
+                "python specific implementations are not supported: cpython-3.12.3-macos-aarch64-none"
+            ),
+        ),
+        (
+            "/usr/bin/python3.8",
+            InvalidVersionConstraintError("python specific implementations are not supported: /usr/bin/python3.8"),
+        ),
+        (">=3.8,<3.10", ">=3.8,<3.10"),
+        (">=3.8, <*", ValueError("Invalid python version: <*")),
+    ],
+)
+def test_python_version_file_adapt(content, expected):
+    """Test that the python version is correctly converted to a PEP440 format.
+
+    Connect expects a PEP440 format, but the .python-version file can contain
+    plain version numbers and other formats.
+
+    We should convert them to the constraints that connect expects.
+    """
+    with tempfile.TemporaryDirectory() as tmpdir:
+        versionfile = pathlib.Path(tmpdir) / ".python-version"
+        with open(versionfile, "w") as tmpfile:
+            tmpfile.write(content)
+
+        try:
+            if isinstance(expected, Exception):
+                with pytest.raises(expected.__class__) as excinfo:
+                    parse_pyversion_python_requires(versionfile)
+                assert str(excinfo.value) == expected.args[0]
+                assert detect_python_version_requirement(tmpdir) is None
+            else:
+                assert parse_pyversion_python_requires(versionfile) == expected
+                assert detect_python_version_requirement(tmpdir) == expected
+        finally:
+            os.remove(tmpfile.name)