Log a warning when an executable is found, but does not have the exec…

pyiron_snippets/resources.py

@@ -10,6 +10,7 @@
 from glob import glob
 import re
 from typing import Any
+import warnings
 
 if os.name == "nt":
     EXE_SUFFIX = "bat"
@@ -21,6 +22,10 @@ class ResourceNotFound(RuntimeError):
     pass
 
 
+class ResolverWarning(RuntimeWarning):
+    pass
+
+
 class AbstractResolver(ABC):
     """
     Interface for resolvers.
@@ -202,6 +207,9 @@ class ExecutableResolver(AbstractResolver):
     and have the executable bit set. :meth:`.search` yields tuples of version strings and full paths to the executable
     instead of plain strings.
 
+    Except on windows results are filtered to make sure all returned scripts have the executable bit set.
+    When the bit is not set, a warning is printed.
+
     >>> exe = ExecutableResolver(..., "lammps")
     >>> exe.list() # doctest: +SKIP
     [
@@ -253,9 +261,18 @@ def _search(self, name):
 
         def cond(path):
             isfile = os.path.isfile(path)
+            # HINT: this is always True on windows
             isexec = os.access(
                 path, os.X_OK, effective_ids=os.access in os.supports_effective_ids
             )
+            if isfile and not isexec:
+                warnings.warn(
+                    f"Found file '{path}', but skipping it because it is not executable!",
+                    category=ResolverWarning,
+                    # TODO: maybe used from python3.12 onwards
+                    # skip_file_prefixes=(os.path.dirname(__file__),),
+                    stacklevel=4,
+                )
             return isfile and isexec
 
         for path in filter(cond, self._resolver.search(self._glob)):

tests/unit/test_resources.py

@@ -1,7 +1,7 @@
 import os
 import os.path
 import unittest
-from pyiron_snippets.resources import ResourceNotFound, ResourceResolver, ExecutableResolver
+from pyiron_snippets.resources import ResourceNotFound, ResourceResolver, ExecutableResolver, ResolverWarning
 
 class TestResolvers(unittest.TestCase):
     """
@@ -55,8 +55,10 @@ def test_executable(self):
         for suffix in (None, "sh", "bat"):
             with self.subTest(suffix=suffix):
                 res = ExecutableResolver([self.res1], code="code1", module="module1", suffix=suffix)
+                # Windows always reports the exec bit as set, so skip those tests there
                 if os.name != "nt":
-                    # no exec bits are present on windows it seems
+                    with self.assertWarns(ResolverWarning):
+                        res.list()
                     self.assertNotIn("versionnonexec", res.available_versions,
                                      "ExecutableResolver must not list scripts that are not executable.")
                 self.assertNotIn("wrong_format", res.available_versions,