marimo incorrectly concludes a class def can't be reused when a class var is reused in class scope

[wkschwartz]

Describe the bug

Marimo says a cell containing the following is a reusable class definition.

class K:
    A: int = 1
    def b(a: int = 1) -> int:
        return a

However, marimo says that a cell containing the following is not a reusable class definition.

class K:
    A: int = 1
    def b(a: int = A) -> int:
        return a

The hover text in the circled question mark in the bottom right corner of the cell says, "This function depends on variables defined by other cells: {'A'}...". The difference between the two snippets is the use in the latter of A in class scope. Here's another example that is also not reusable according to marimo:

class K:
    A: int = 1
    B: int = A
    def b(a: int = 1) -> int:
        return a

The correct behavior would be to notice that A was defined in class scope and does not come from another cell (and does not leak out of this cell except through class K).

Will you submit a PR?

No

Environment

Details

{
  "marimo": "0.18.0",
  "editable": false,
  "location": "$LOCALAPPDATA/uv/cache/archive-v0/vVa0LoFIQedWJEgGGbZoX/Lib/site-packages/marimo",
  "OS": "Windows",
  "OS Version": "11",
  "Processor": "Intel64 Family 6 Model 186 Stepping 3, GenuineIntel",
  "Python Version": "3.13.7",
  "Locale": "en_US",
  "Binaries": {
    "Browser": "133.0.6943.99",
    "Node": "--"
  },
  "Dependencies": {
    "click": "8.3.1",
    "docutils": "0.22.3",
    "itsdangerous": "2.2.0",
    "jedi": "0.19.2",
    "markdown": "3.10",
    "narwhals": "2.12.0",
    "packaging": "25.0",
    "psutil": "7.1.3",
    "pygments": "2.19.2",
    "pymdown-extensions": "10.17.1",
    "pyyaml": "6.0.3",
    "starlette": "0.50.0",
    "tomlkit": "0.13.3",
    "typing-extensions": "4.15.0",
    "uvicorn": "0.38.0",
    "websockets": "15.0.1"
  },
  "Optional Dependencies": {
    "loro": "1.8.2",
    "python-lsp-ruff": "2.3.0",
    "python-lsp-server": "1.13.2",
    "ruff": "0.14.6"
  },
  "Experimental Flags": {}
}

Code to reproduce

See description above.