diff --git a/src/cleo/commands/completions_command.py b/src/cleo/commands/completions_command.py
index 6a9df744..80f27947 100644
--- a/src/cleo/commands/completions_command.py
+++ b/src/cleo/commands/completions_command.py
@@ -14,6 +14,7 @@
 from cleo._compat import shell_quote
 from cleo.commands.command import Command
 from cleo.commands.completions.templates import TEMPLATES
+from cleo.exceptions import CleoRuntimeError
 
 
 if TYPE_CHECKING:
@@ -137,10 +138,32 @@ def render(self, shell: str) -> str:
 
         raise RuntimeError(f"Unrecognized shell: {shell}")
 
+    @staticmethod
+    def _get_prog_name_from_stack() -> str:
+        package_name = ""
+        frame = inspect.currentframe()
+        f_back = frame.f_back if frame is not None else None
+        f_globals = f_back.f_globals if f_back is not None else None
+        # break reference cycle
+        # https://docs.python.org/3/library/inspect.html#the-interpreter-stack
+        del frame
+
+        if f_globals is not None:
+            package_name = f_globals.get("__name__")
+
+            if package_name == "__main__":
+                package_name = f_globals.get("__package__")
+
+            if package_name:
+                package_name = package_name.partition(".")[0]
+
+        if not package_name:
+            raise CleoRuntimeError("Can not determine package name")
+
+        return package_name
+
     def _get_script_name_and_path(self) -> tuple[str, str]:
-        # FIXME: when generating completions via `python -m script completions`,
-        # we incorrectly infer `script_name` as `__main__.py`
-        script_name = self._io.input.script_name or inspect.stack()[-1][1]
+        script_name = self._io.input.script_name or self._get_prog_name_from_stack()
         script_path = posixpath.realpath(script_name)
         script_name = os.path.basename(script_path)
 
@@ -215,6 +238,7 @@ def sanitize(s: str) -> str:
                 self._zsh_describe(f"--{opt.name}", sanitize(opt.description))
                 for opt in sorted(cmd.definition.options, key=lambda o: o.name)
             )
+
             cmds_opts += [
                 f"            ({command_name})",
                 f"            opts+=({options})",
@@ -258,11 +282,12 @@ def sanitize(s: str) -> str:
                 f"complete -c {script_name} -f -n '__fish{function}_no_subcommand' "
                 f"-a {command_name} -d '{sanitize(cmd.description)}'"
             )
+
             cmds_opts += [
-                f"# {command_name}",
+                f"# {cmd.name}",
                 *[
                     f"complete -c {script_name} -A "
-                    f"-n '__fish_seen_subcommand_from {sanitize(command_name)}' "
+                    f"""-n '__fish_seen_subcommand_from "{cmd.name}"' """
                     f"-l {opt.name} -d '{sanitize(opt.description)}'"
                     for opt in sorted(cmd.definition.options, key=lambda o: o.name)
                 ],