Improve Windows support

.changelog/_unreleased.toml

@@ -4,6 +4,20 @@ type = "feature"
 description = "Make Rust builds respect Cargo.lock when present"
 author = "[email protected]"
 
+[[entries]]
+id = "ebe30d77-1206-4437-8aa2-7373e9335926"
+type = "improvement"
+description = "Improve Windows support in `krakenw` by supporting the `PYENV` env-var and using the right `pyhon.exe` path on Windows"
+author = "@NiklasRosenstein"
+component = "kraken-wrapper"
+
+[[entries]]
+id = "a8200c89-b05a-46ce-895c-c4a4f5a736a6"
+type = "fix"
+description = "Do not use `dmypy` on Windows"
+author = "@NiklasRosenstein"
+component = "kraken-build"
+
 [[entries]]
 id = "db65bd12-a9d1-472c-a38b-6f889cdda683"
 type = "improvement"

kraken-build/src/kraken/common/findpython.py

@@ -141,12 +141,25 @@ def get_candidates(
         if match:
             yield {"path": str(command), "exact_version": match.group(1)}
 
-    # pyenv
-    pyenv_versions = Path("~/.pyenv/versions").expanduser()
-    if check_pyenv and pyenv_versions.is_dir():
+    # pyenv (+Windows)
+    if check_pyenv:
+        pyenv_versions = Path("~/.pyenv/versions").expanduser()
+        if not pyenv_versions.is_dir():
+            pyenv = os.getenv("PYENV")
+            if pyenv:
+                pyenv_versions = Path(pyenv).expanduser().joinpath("versions")
+            elif os.name == "nt":
+                pyenv_versions = Path("~/.pyenv/pyenv-win/versions").expanduser()
+    else:
+        pyenv_versions = None
+
+    if pyenv_versions and pyenv_versions.is_dir():
         for item in pyenv_versions.iterdir():
             if re.match(r"\d+\.\d+\.\d+$", item.name) and item.is_dir():
-                yield {"path": str(item / "bin" / "python"), "exact_version": item.name}
+                if os.name == "nt":
+                    yield {"path": str(item / "python.exe"), "exact_version": item.name}
+                else:
+                    yield {"path": str(item / "bin" / "python"), "exact_version": item.name}
 
     yield {"path": sys.executable, "exact_version": ".".join(map(str, sys.version_info[:3]))}
 
@@ -192,7 +205,7 @@ def evaluate_candidates(
         if version is None:
             try:
                 version = get_python_interpreter_version(str(path))
-            except (subprocess.CalledProcessError, RuntimeError):
+            except (subprocess.CalledProcessError, RuntimeError, FileNotFoundError):
                 logger.debug("Failed to get version for Python interpreter %s", path, exc_info=True)
                 continue
             if cache:

kraken-build/src/kraken/std/python/tasks/base_task.py

@@ -4,6 +4,7 @@
 import os
 import shutil
 import subprocess as sp
+import sys
 from collections.abc import Iterable, MutableMapping
 
 from deprecated import deprecated
@@ -77,5 +78,6 @@ def execute(self) -> TaskStatus:
                 logger.warning('%s = "*"', dep)
             return TaskStatus.failed("The %s dependencies are missing" % self.python_dependencies)
         logger.info("%s", command)
-        result = sp.call(command, cwd=self.project.directory, env=env)
+        shell = sys.platform.startswith("win32")  # Windows requires shell to find executable in path
+        result = sp.call(command, cwd=self.project.directory, env=env, shell=shell)
         return self.handle_exit_code(result)

kraken-build/src/kraken/std/python/tasks/mypy_task.py

@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+import logging
+import sys
 from collections.abc import MutableMapping, Sequence
 from pathlib import Path
 
@@ -9,6 +11,8 @@
 
 from .base_task import EnvironmentAwareDispatchTask
 
+logger = logging.getLogger(__name__)
+
 
 class MypyTask(EnvironmentAwareDispatchTask):
     description = "Static type checking for Python code using Mypy."
@@ -24,7 +28,12 @@ class MypyTask(EnvironmentAwareDispatchTask):
     # EnvironmentAwareDispatchTask
 
     def get_execute_command_v2(self, env: MutableMapping[str, str]) -> list[str]:
-        entry_point = "dmypy" if self.use_daemon.get() else "mypy"
+        use_daemon = self.use_daemon.get()
+        if use_daemon and sys.platform.startswith("win32"):
+            use_daemon = False
+            logger.warning("Disable use of mypy daemon due to error in exit code on Windows")
+
+        entry_point = "dmypy" if use_daemon else "mypy"
 
         if mypy_pex_bin := self.mypy_pex_bin.get():
             # See https://pex.readthedocs.io/en/latest/api/vars.html
@@ -38,7 +47,7 @@ def get_execute_command_v2(self, env: MutableMapping[str, str]) -> list[str]:
         #       happens regularly but is hard to detect automatically).
 
         status_file = (self.project.directory / ".dmypy.json").absolute()
-        if self.use_daemon.get():
+        if use_daemon:
             command += ["--status-file", str(status_file), "run", "--"]
         if mypy_pex_bin:
             # Have mypy pick up the Python executable from the virtual environment that is activated automatically