fix argument splitting on '--' in the command line

marimo/_cli/cli.py

@@ -1119,6 +1119,15 @@ def run(
         run_in_sandbox,
     )
 
+    # click consumes `--` as an option terminator and does not pass it
+    # through to `args`. Recover this sentinel from raw argv so splitting
+    # logic can preserve "args after --" semantics.
+    if "--" not in args and "--" in sys.argv[1:]:
+        double_dash_index = sys.argv[1:].index("--")
+        tail_after_double_dash = tuple(sys.argv[double_dash_index + 2 :])
+        if tail_after_double_dash == args:
+            args = ("--",) + args
+
     paths, notebook_args = _split_run_paths_and_args(name, args)
 
     if len(paths) == 1 and prompt_run_in_docker_container(

tests/_cli/test_cli.py

@@ -22,6 +22,7 @@
 from typing import TYPE_CHECKING, Any
 from unittest.mock import patch
 
+import click
 import pytest
 from click.testing import CliRunner
 
@@ -1720,6 +1721,48 @@ def test_cli_run_sandbox_prompt_yes() -> None:
     p.kill()
 
 
+@pytest.mark.parametrize(
+    "tail_args",
+    [
+        ["experiment_name=my-exp", "epochs=25"],
+        ["--key", "value"],
+        ["--key"],
+        ["-key", "value"],
+    ],
+)
+def test_cli_run_double_dash_reaches_splitter(tail_args: list[str]) -> None:
+    runner = CliRunner()
+    captured: dict[str, Any] = {}
+
+    def _capture(
+        name: str, args: tuple[str, ...]
+    ) -> tuple[list[str], tuple[str, ...]]:
+        captured["name"] = name
+        captured["args"] = args
+        raise click.ClickException("stop after capture")
+
+    with (
+        patch(
+            "marimo._cli.cli._split_run_paths_and_args", side_effect=_capture
+        ),
+        patch(
+            "marimo._cli.cli.sys.argv",
+            ["marimo", "run", "notebook.py", "--", *tail_args],
+        ),
+    ):
+        result = runner.invoke(
+            cli_main,
+            ["run", "notebook.py", "--", *tail_args],
+        )
+
+    assert result.exit_code != 0
+    assert "stop after capture" in result.output
+    assert captured["name"] == "notebook.py"
+    # Desired behavior: splitter should receive the `--` sentinel.
+    # This currently fails because click consumes `--` before invoking the command.
+    assert captured["args"] == ("--", *tail_args)
+
+
 def test_cli_with_custom_pyproject_config(tmp_path: Path) -> None:
     # Create a custom pyproject.toml with special marimo config
     pyproject_path = tmp_path / "pyproject.toml"