Make entrypoint script less noticeable. (#365)

Fixes #361

Author: zooba

src/manage/aliasutils.py

@@ -21,26 +21,38 @@
 
 SCRIPT_CODE = """import sys
 
+# Avoid letting __main__.__file__ lead back to this script
 try:
-    if not sys.path[0]:
-        del sys.path[0]
-except AttributeError:
+    __file__ = None
+except Exception:
     pass
-except IndexError:
+
+# Also clear __spec__.origin when it exists
+try:
+    __spec__.origin = None
+except Exception:
     pass
 
 # Replace argv[0] with our executable instead of the script name.
 try:
     if sys.argv[0][-14:].upper() == ".__SCRIPT__.PY":
         sys.argv[0] = sys.argv[0][:-14]
-        sys.orig_argv[0] = sys.argv[0]
 except AttributeError:
     pass
 except IndexError:
     pass
 
-from {mod} import {func}
-sys.exit({func}())
+if __name__ == "__main__":
+    try:
+        if not sys.path[0]:
+            del sys.path[0]
+    except AttributeError:
+        pass
+    except IndexError:
+        pass
+
+    from {mod} import {func}
+    sys.exit({func}())
 """