no-mistakes: apply CI fixes

Author: ruby-dlee

tests/test_build_sealed_bridge_runtimes.py

@@ -30,28 +30,19 @@ def sha(path: Path) -> str:
     return hashlib.sha256(path.read_bytes()).hexdigest()
 
 
-def host_system_tool_paths() -> dict[str, Path]:
+def host_system_tool_paths(fallback: Path) -> dict[str, Path]:
     def usable(path: Path) -> bool:
         try:
-            metadata = path.lstat()
-        except OSError:
+            builder._require_regular(
+                path,
+                "fixture system tool",
+                executable=True,
+                allow_root_owner=True,
+            )
+        except (OSError, builder.BuildError):
             return False
-        return (
-            stat.S_ISREG(metadata.st_mode)
-            and metadata.st_uid == 0
-            and not stat.S_IMODE(metadata.st_mode) & 0o022
-            and Path(os.path.realpath(path)) == path
-            and os.access(path, os.X_OK)
-        )
+        return Path(os.path.realpath(path)) == path
 
-    fallback = next(
-        path
-        for path in map(
-            Path,
-            ("/usr/bin/true", "/bin/true", "/usr/bin/env", "/bin/echo"),
-        )
-        if usable(path)
-    )
     return {
         name: path if usable(path) else fallback
         for name, path in builder.SYSTEM_TOOL_PATHS.items()
@@ -180,8 +171,11 @@ class SealedRuntimeBuilderTests(unittest.TestCase):
     def setUp(self) -> None:
         self.temporary = tempfile.TemporaryDirectory(prefix="sealed-builder-test-")
         self.root = Path(os.path.realpath(self.temporary.name))
+        fallback = self.root / "system-tool"
+        fallback.write_text("#!/bin/sh\nexit 0\n", encoding="utf-8")
+        fallback.chmod(0o700)
         self.system_tools_patch = mock.patch.object(
-            builder, "SYSTEM_TOOL_PATHS", host_system_tool_paths()
+            builder, "SYSTEM_TOOL_PATHS", host_system_tool_paths(fallback)
         )
         self.system_tools_patch.start()
         self.fixture = ManifestFixture(self.root)