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ROLLOUT 2 · ecmwf/earthkit-data

ecmwf__earthkit-data-111

Solved

322 stotal time

17tool calls

28model calls

4,588tokens generated

266,369prompt tokens read

No error recorded

⚠ The request log has 27 model calls but the trace has 29 agent calls, so tokens are listed separately instead of beside each turn.

Turn by turn

Token shading: p ≥ 0.9 0.5 – 0.9 0.2 – 0.5 below 0.2. Hover a token for its id and probability.

System instructions 4,822 characters

You are a principal Python software engineer resolving a repository issue in `/workspace`.
Your sole objective is to produce a minimal, root-cause source patch that passes every hidden fail-to-pass and pass-to-pass regression test on the first grading run.

## Critical Environment & Grader Rules
1. **Air-Gapped Sandbox & Available CLI Tools**: No network access. Never run `pip`, `uv`, `conda`, or `git fetch`. Note: `rg` (`ripgrep`) is NOT installed in the container — always use `grep -rn --include="*.py"` for fast exact searches so you never waste a tool call on `command not found`.
2. **Protected Grading Paths**: Before running official verification, the grading harness **strips and reverts all changes** to `tests/`, `test/`, `testing/`, `test_*.py`, `*_test.py`, `conftest.py`, `pyproject.toml`, `setup.cfg`, `pytest.ini`, and `tox.ini`. Every part of your fix MUST reside in non-test production source files.
3. **Untracked File Trap (`git add -N .`)**: `submit_patch` stages ALL untracked files inside `/workspace`! Never leave reproduction or scratch files inside `/workspace` — run reproductions inline via `python3 - <<'PY'` or inside `/tmp/repro.py` in a single `run_command`.
4. **Stdout Truncation Rule**: `run_command` truncates stdout after the first 5,000 characters from the TOP. Always run pytest quietly with short tracebacks:
`pytest path/to/test_file.py -k pattern -q --tb=short --no-header`
If a test file is large, redirect output to `/tmp/pytest.log` and inspect `tail -n 80 /tmp/pytest.log` so failure tracebacks at the bottom are never cut off.
5. **Strict Pacing Discipline**: `get_status` and `submit_patch` are free and do NOT count toward `max_tool_calls`. Target **16-22 counted tool calls total**, and **begin your first `edit_file` change no later than tool call 15**. Reserve at least 4 calls for verification, `git status --short && git diff`, and submission.

## Execution Protocol

### Phase 1 — Pinpoint Code & Tests Immediately (1-2 tool calls)
- The user message already contains `Workspace Layout` — do NOT waste a turn running `ls` on top-level directories.
- Run a single compound `run_command` with `grep -rn --include="*.py"` to locate:
(a) the exact symbols, error strings, or functions from the problem description,
(b) **all parallel or sibling implementations** (for example sync + async variants, `Client` + `AsyncClient`, serializer + deserializer, multiple backends/dialects, base + subclass methods, `__init__.py` / `__all__` exports), and
(c) the closest existing unit test files under `tests/`.

### Phase 2 — Deep Read & Spec Anchor (2-5 tool calls)
- Use `read_file` with generous `start_line` and `end_line` windows (180-300 lines per call so you read whole modules in fewer calls) on the target function/class, callers, type annotations, and neighboring tests.
- Before editing, verify every explicit and implicit requirement from the issue: exact parameter names, defaults, boundary/domain edge cases, exception types/messages, `None` vs empty collection vs falsy (`0`, `False`, `""`) semantics, mutability/copying, and return types.

### Phase 3 — Reproduce Bug in One Call (1 tool call)
- Run ONE concise command (`python3 - <<'PY' ... PY` or targeted `pytest ... -q --tb=short --no-header`) via `run_command` to observe the exact pre-fix failure. Do NOT spend multiple tool calls writing separate reproduction scripts.

### Phase 4 — Surgical Implementation Across All Parallel Paths (1-4 tool calls)
- Begin editing by tool call 15! Use `edit_file` with 4-6 lines of exact surrounding context copied from `read_file`.
- Update ALL parallel codepaths (sync/async, multiple classes/dialects, type hints) consistently so partial fixes do not fail sibling tests.
- **2-Strike Edit Rule**: If `edit_file` fails twice on the same block due to whitespace or escaping, do not retry `edit_file` a third time — apply an atomic Python transformation via `run_command` and immediately verify `python3 -m py_compile path/to/file.py`.

### Phase 5 — Edge-Case Verification, Diff Hygiene & Clean Exit (2-4 tool calls)
- Run a single compound `run_command` testing both your reproduction + boundary edge cases (`None`, empty input, leading/trailing delimiters, subdomain/prefix boundaries, subclass/async parity) AND the relevant existing `pytest` module(s) with `-q --tb=short --no-header`.
- Run `git status --short && git diff` via `run_command`. Confirm:
- ZERO untracked (`??`) files in `/workspace` (`rm -f` any untracked workspace files immediately),
- ZERO modifications to `tests/` or protected config files (`git checkout -- tests/` if touched),
- Minimal, clean diff with valid imports and indentation.
- Call `submit_patch` once verification passes, then respond with a brief 2-sentence plain-text summary and make NO further tool calls.

Task prompt 2,913 characters

You are evaluating a software engineering task for repository ecmwf/earthkit-data.

Problem Statement:
to_pandas fails for bufr when no filters argument specified
### What happened?

Running this code:

```
ds = earthkit.data.from_source("file", "synop.bufr")
r = ds.to_pandas(columns=["latitude", "longitude"])
```
results in the following error:
```
File "git/pdbufr/pdbufr/bufr_structure.py", line 616, in stream_bufr
filters = dict(filters)
TypeError: 'NoneType' object is not iterable
```

To make it work `filters` must be specified. E.g.:

`r = ds.to_pandas(columns=["latitude", "longitude"], filters={})`

### What are the steps to reproduce the bug?

See above

### Version

0.1.3, develop

### Platform (OS and architecture)

all

### Relevant log output

_No response_

### Accompanying data

_No response_

### Organisation

_No response_

## Task Budget (Session terminates when any budget is exhausted)
- Time allowance: 7.5 minutes
- Tool calls allowance: 30 calls
- Max loop iterations: 40 turns

## Execution Environment Rules
- Single command timeout: 90 seconds (commands exceeding this fail without ending the session)
- Command output limit: 5000 characters
- File view limit: 150 lines per read_file call
- File character limit: 10000 characters per read_file call
- Environment is offline (no network/PyPI access). All repository and test dependencies are ALREADY pre-installed. Do NOT attempt to run pip install or download packages.

## Instructions:
0. All source code is under `/workspace`. Do NOT search outside `/workspace` (e.g. `/usr/`, `/wheels/`, system site-packages). If imports fail, the issue is in the source code under `/workspace`, not in missing system packages.
1. Analyze the problem statement and any provided hints carefully to identify all requested script paths, CLI subcommands, or Python modules.
2. Inspect existing codebase conventions and test files before making edits.
3. Verify your implementation using targeted tests or inline assertions before submitting.
4. Call submit_patch only after your implementation is complete and verified.
5. As your final action, you must return a text-only response reporting your completion to terminate the session.
## Workspace Layout
The repository is located at `/workspace`. Here is the directory tree (up to 3 levels):
```
./LICENSE
./Makefile
./README.md
./docs
./earthkit
./earthkit/data
./earthkit/data/__init__.py
./earthkit/data/arguments
./earthkit/data/core
./earthkit/data/data
./earthkit/data/decorators.py
./earthkit/data/indexing
./earthkit/data/input_manager.py
./earthkit/data/mergers
./earthkit/data/mirrors
./earthkit/data/readers
./earthkit/data/sources
./earthkit/data/sphinxext
./earthkit/data/testing.py
./earthkit/data/translators
./earthkit/data/utils
./earthkit/data/vocabularies
./earthkit/data/wrappers
./environment.yml
./pyproject.toml
./pytest.ini
./setup.cfg
./tests
```

Turn 1at 38 s356 tokens out2,836 prompt tokens

The user is reporting a `TypeError: 'NoneType' object is not iterable` when calling `to_pandas` on a BUFR dataset when the `filters` argument is not specified.
The error occurs in `git/pdbufr/pdbufr/bufr_structure.py`, line 616, in `stream_bufr`.
However, `pdbufr` seems to be an external dependency (or a submodule/integrated package), but I should first check where `to_pandas` is implemented in `earthkit.data`.

The problem description says:
```python
ds = earthkit.data.from_source("file", "synop.bufr")
r = ds.to_pandas(columns=["latitude", "longitude"])
```
results in:
```
File "git/pdbufr/pdbufr/bufr_structure.py", line 616, in stream_bufr
    filters = dict(filters)
TypeError: 'NoneType' object is not iterable
```

Wait, `git/pdbufr/pdbufr/bufr_structure.py` looks like it might be in a subprocess or another package. But I am in `/workspace`. Let me check if `pdbufr` is part of the workspace or an installed package.
`earthkit.data` seems to be the main package here.

Let's start by finding where `to_pandas` is defined in `earthkit.data`.

TOOL CALL · run_command

{
  "command": "grep -rn --include=\"*.py\" \"def to_pandas\" earthkit/data"
}

Result of run_command 1,248 characters

{
  "status": "ok",
  "stdout": "earthkit/data/core/statistics.py:71:    def to_pandas(self):\nearthkit/data/core/__init__.py:47:    def to_pandas(self, **kwargs):\nearthkit/data/mergers/__init__.py:74:    def to_pandas(self, **kwargs):\nearthkit/data/mergers/__init__.py:113:    def to_pandas(self, *args, **kwargs):\nearthkit/data/sources/multi.py:100:    def to_pandas(self, **kwargs):\nearthkit/data/sources/cds.py:130:    def to_pandas(self, **kwargs):\nearthkit/data/sources/memory.py:41:    def to_pandas(self, **kwargs):\nearthkit/data/sources/ecmwf_api.py:99:    def to_pandas(self, **kwargs):\nearthkit/data/sources/file.py:105:    def to_pandas(self, **kwargs):\nearthkit/data/wrappers/xarray.py:71:    def to_pandas(self, *args, **kwargs):\nearthkit/data/readers/bufr.py:40:    def to_pandas(self, columns=COLUMNS, filters=None, **kwargs):\nearthkit/data/readers/grib/pandas.py:16:    def to_pandas(self, latitude=None, longitude=None, **kwargs):\nearthkit/data/readers/netcdf.py:191:    def to_pandas(self):\nearthkit/data/readers/netcdf.py:377:    def to_pandas(self):\nearthkit/data/readers/odb.py:18:    def to_pandas(self, **kwargs):\nearthkit/data/readers/csv.py:135:    def to_pandas(self, **kwargs):\n",
  "stderr": "",
  "exit_code": 0
}

Turn 2at 52 s103 tokens out3,682 prompt tokens

The most relevant one for BUFR is likely `earthkit/data/readers/bufr.py:40: def to_pandas(self, columns=COLUMNS, filters=None, **kwargs):`.

Let's examine `earthkit/data/readers/bufr.py`.

TOOL CALL · read_file

{
  "end_line": 100,
  "filepath": "earthkit/data/readers/bufr.py",
  "start_line": 1
}

Result of read_file 3,239 characters

{
  "status": "ok",
  "filepath": "earthkit/data/readers/bufr.py",
  "content": "# (C) Copyright 2020 ECMWF.\n#\n# This software is licensed under the terms of the Apache Licence Version 2.0\n# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.\n# In applying this licence, ECMWF does not waive the privileges and immunities\n# granted to it by virtue of its status as an intergovernmental organisation\n# nor does it submit to any jurisdiction.\n#\n\n# See:\n# https://github.com/ecmwf/pdbufr\nfrom . import Reader\n\nCOLUMNS = (\"latitude\", \"longitude\", \"data_datetime\")\n\nBUFR_LS_KEYS = {\n    \"edition\": \"edition\",\n    \"type\": \"dataCategory\",\n    \"subtype\": \"dataSubCategory\",\n    \"c\": \"bufrHeaderCentre\",\n    \"mv\": \"masterTablesVersionNumber\",\n    \"lv\": \"localTablesVersionNumber\",\n    \"subsets\": \"numberOfSubsets\",\n    \"compr\": \"compressedData\",\n    \"typicalDate\": \"typicalDate\",\n    \"typicalTime\": \"typicalTime\",\n    \"ident\": \"ident\",\n    \"lat\": \"localLatitude\",\n    \"lon\": \"localLongitude\",\n}\n\n\nclass BUFRReader(Reader):\n    \"\"\"Represents a BUFR file\"\"\"\n\n    def __init__(self, source, path):\n        super().__init__(source, path)\n        self._num = None\n\n    def to_pandas(self, columns=COLUMNS, filters=None, **kwargs):\n        \"\"\"Extracts BUFR data into an pandas DataFranme using :xref:`pdbufr`.\n\n        Parameters\n        ----------\n        columns: str, sequence[str]\n            List of ecCodes BUFR keys to extract for each BUFR message/subset.\n            See: :xref:`read_bufr` for details.\n        filters: dict\n            Defines the conditions when to extract the specified ``columns``. See:\n            :xref:`read_bufr` for details.\n        **kwargs: dict, optional\n            Other keyword arguments:\n\n        Returns\n        -------\n        Pandas DataFrame\n\n        Examples\n        --------\n        :ref:`/examples/bufr.ipynb`\n\n        \"\"\"\n        import pdbufr\n\n        return pdbufr.read_bufr(self.path, columns=columns, filters=filters)\n\n    def __len__(self):\n        if self._num is None:\n            import eccodes\n\n            with open(self.path, \"rb\") as f:\n                self._num = eccodes.codes_count_in_file(f)\n        return self._num\n\n    def ls(self, *args, **kwargs):\n        from pdbufr.high_level_bufr.bufr import BufrFile\n\n        from earthkit.data.utils.summary import ls\n\n        b = BufrFile(self.path)\n\n        def _proc(keys, n):\n            count_start = 0\n            if n is None:\n                count_end = len(self)\n            elif n > 0:\n                count_end = n\n            else:\n                num = len(self)\n                count_start = max(0, num + n)\n                count_end = num\n\n            for count, msg in enumerate(b):\n                with msg:\n                    if count_start <= count < count_end:\n                        yield ({k: msg[k1] for k, k1 in keys.items()})\n                    elif count >= count_end:\n                        break\n\n        return ls(_proc, BUFR_LS_KEYS, *args, **kwargs)",
  "start_line": 1,
  "end_line": 100,
  "total_lines": 105,
  "is_truncated": false
}

Turn 3at 78 s337 tokens out4,765 prompt tokens

The `to_pandas` method in `BUFRReader` calls `pdbufr.read_bufr(self.path, columns=columns, filters=filters)`.
If `filters` is `None` (its default value), it's passed as `None` to `pdbufr.read_bufr`.

The error message says:
```
File "git/pdbufr/pdbufr/bufr_structure.py", line 616, in stream_bufr
    filters = dict(filters)
TypeError: 'NoneType' object is not iterable
```
This indicates that `pdbufr` is expecting `filters` to be iterable (like a dict) and doesn't handle `None`.
Since `pdbufr` seems to be an external library (though the path in the error message `git/pdbufr/...` is strange, it might be how it's installed or called if it's a git submodule, but it's not in `/workspace/pdbufr`), we should fix it in `earthkit.data` by ensuring `filters` is at least an empty dict if it is `None`.

Wait, if I can't modify `pdbufr`, I must modify the caller in `earthkit/data/readers/bufr.py`.

Let's check if there are other places where `pdbufr` is used in `earthkit.data`.

TOOL CALL · run_command

{
  "command": "grep -rn \"pdbufr\" earthkit/data"
}

Result of run_command 501 characters

{
  "status": "ok",
  "stdout": "earthkit/data/readers/bufr.py:11:# https://github.com/ecmwf/pdbufr\nearthkit/data/readers/bufr.py:41:        \"\"\"Extracts BUFR data into an pandas DataFranme using :xref:`pdbufr`.\nearthkit/data/readers/bufr.py:63:        import pdbufr\nearthkit/data/readers/bufr.py:65:        return pdbufr.read_bufr(self.path, columns=columns, filters=filters)\nearthkit/data/readers/bufr.py:76:        from pdbufr.high_level_bufr.bufr import BufrFile\n",
  "stderr": "",
  "exit_code": 0
}

Turn 4at 85 s83 tokens out5,307 prompt tokens

It only appears in `earthkit/data/readers/bufr.py`.

Now I want to reproduce the bug. I don't have a `synop.bufr` file, but I can try to mock it or find if there are any existing BUFR tests.

TOOL CALL · run_command

{
  "command": "find tests -name \"*bufr*\""
}

Result of run_command 105 characters

{
  "status": "ok",
  "stdout": "tests/bufr\ntests/bufr/test_bufr_summary.py\n",
  "stderr": "",
  "exit_code": 0
}

Turn 5at 87 s49 tokens out5,449 prompt tokens

Let's look at `tests/bufr/test_bufr_summary.py`.

TOOL CALL · read_file

{
  "filepath": "tests/bufr/test_bufr_summary.py"
}

Result of read_file 3,979 characters

{
  "status": "ok",
  "filepath": "tests/bufr/test_bufr_summary.py",
  "content": "#!/usr/bin/env python3\n\n# (C) Copyright 2022- ECMWF.\n#\n# This software is licensed under the terms of the Apache Licence Version 2.0\n# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.\n# In applying this licence, ECMWF does not waive the privileges and immunities\n# granted to it by virtue of its status as an intergovernmental organisation\n# nor does it submit to any jurisdiction.\n\nimport pytest\n\nfrom earthkit.data import from_source\nfrom earthkit.data.testing import earthkit_examples_file\n\n\ndef test_bufr_ls_invalid_num():\n    f = from_source(\"file\", earthkit_examples_file(\"temp_10.bufr\"))\n    with pytest.raises(ValueError):\n        f.ls(n=0, print=False)\n\n    with pytest.raises(ValueError):\n        f.ls(0, print=False)\n\n\ndef test_bufr_ls_num():\n    f = from_source(\"file\", earthkit_examples_file(\"temp_10.bufr\"))\n\n    # default keys\n\n    # head\n    df = f.ls(n=2, print=False)\n    ref = {\n        \"edition\": {0: 3, 1: 3},\n        \"type\": {0: 2, 1: 2},\n        \"subtype\": {0: 101, 1: 101},\n        \"c\": {0: 98, 1: 98},\n        \"mv\": {0: 13, 1: 13},\n        \"lv\": {0: 1, 1: 1},\n        \"subsets\": {0: 1, 1: 1},\n        \"compr\": {0: 0, 1: 0},\n        \"typicalDate\": {0: \"20081208\", 1: \"20081208\"},\n        \"typicalTime\": {0: \"120000\", 1: \"120000\"},\n        \"ident\": {0: \"02836\", 1: \"01400\"},\n        \"lat\": {0: 67.37, 1: 56.9},\n        \"lon\": {0: 26.63, 1: 3.35},\n    }\n\n    assert ref == df.to_dict()\n\n    # t tail\n    df = f.ls(-2, print=False)\n    ref = {\n        \"edition\": {0: 3, 1: 3},\n        \"type\": {0: 2, 1: 2},\n        \"subtype\": {0: 101, 1: 101},\n        \"c\": {0: 98, 1: 98},\n        \"mv\": {0: 13, 1: 13},\n        \"lv\": {0: 1, 1: 1},\n        \"subsets\": {0: 1, 1: 1},\n        \"compr\": {0: 0, 1: 0},\n        \"typicalDate\": {0: \"20081208\", 1: \"20081208\"},\n        \"typicalTime\": {0: \"120000\", 1: \"120000\"},\n        \"ident\": {0: \"11035\", 1: \"02963\"},\n        \"lat\": {0: 48.25, 1: 60.82},\n        \"lon\": {0: 16.37, 1: 23.5},\n    }\n\n    assert ref == df.to_dict()\n\n    df = f.ls(-2, print=False)\n    assert ref == df.to_dict()\n\n\ndef test_bufr_head_num():\n    f = from_source(\"file\", earthkit_examples_file(\"temp_10.bufr\"))\n\n    # default keys\n    df = f.head(n=2, print=False)\n    ref = {\n        \"edition\": {0: 3, 1: 3},\n        \"type\": {0: 2, 1: 2},\n        \"subtype\": {0: 101, 1: 101},\n        \"c\": {0: 98, 1: 98},\n        \"mv\": {0: 13, 1: 13},\n        \"lv\": {0: 1, 1: 1},\n        \"subsets\": {0: 1, 1: 1},\n        \"compr\": {0: 0, 1: 0},\n        \"typicalDate\": {0: \"20081208\", 1: \"20081208\"},\n        \"typicalTime\": {0: \"120000\", 1: \"120000\"},\n        \"ident\": {0: \"02836\", 1: \"01400\"},\n        \"lat\": {0: 67.37, 1: 56.9},\n        \"lon\": {0: 26.63, 1: 3.35},\n    }\n\n    assert ref == df.to_dict()\n\n    df = f.head(2, print=False)\n    assert ref == df.to_dict()\n\n\ndef test_bufr_tail_num():\n    f = from_source(\"file\", earthkit_examples_file(\"temp_10.bufr\"))\n\n    # default keys\n    df = f.tail(n=2, print=False)\n    ref = {\n        \"edition\": {0: 3, 1: 3},\n        \"type\": {0: 2, 1: 2},\n        \"subtype\": {0: 101, 1: 101},\n        \"c\": {0: 98, 1: 98},\n        \"mv\": {0: 13, 1: 13},\n        \"lv\": {0: 1, 1: 1},\n        \"subsets\": {0: 1, 1: 1},\n        \"compr\": {0: 0, 1: 0},\n        \"typicalDate\": {0: \"20081208\", 1: \"20081208\"},\n        \"typicalTime\": {0: \"120000\", 1: \"120000\"},\n        \"ident\": {0: \"11035\", 1: \"02963\"},\n        \"lat\": {0: 48.25, 1: 60.82},\n        \"lon\": {0: 16.37, 1: 23.5},\n    }\n\n    assert ref == df.to_dict()\n\n    df = f.tail(2, print=False)\n    assert ref == df.to_dict()",
  "start_line": 1,
  "end_line": 126,
  "total_lines": 126,
  "is_truncated": false
}

Turn 6at 110 s215 tokens out7,348 prompt tokens

The tests use `earthkit_examples_file("temp_10.bufr")`. I can use this to reproduce the bug.

I'll create a reproduction script `repro.py`.

TOOL CALL · write_file

{
  "content": "from earthkit.data import from_source\nfrom earthkit.data.testing import earthkit_examples_file\nimport pandas as pd\n\ntry:\n    f = from_source(\"file\", earthkit_examples_file(\"temp_10.bufr\"))\n    print(\"Attempting to call to_pandas without filters...\")\n    r = f.to_pandas(columns=[\"latitude\", \"longitude\"])\n    print(\"Success!\")\n    print(r)\nexcept TypeError as e:\n    print(f\"Caught expected TypeError: {e}\")\nexcept Exception as e:\n    print(f\"Caught unexpected exception: {type(e).__name__}: {e}\")\n",
  "filepath": "repro.py"
}

Result of write_file 53 characters

{
  "status": "ok",
  "filepath": "repro.py",
  "size": 498
}

Turn 7at 112 s28 tokens out7,601 prompt tokens

Now let's run it.

TOOL CALL · run_command

{
  "command": "python3 repro.py"
}

Result of run_command 171 characters

{
  "status": "ok",
  "stdout": "Attempting to call to_pandas without filters...\nCaught expected TypeError: 'NoneType' object is not iterable\n",
  "stderr": "",
  "exit_code": 0
}

Turn 8at 124 s179 tokens out7,692 prompt tokens

The bug is reproduced.

Now let's check if specifying `filters={}` works as claimed in the problem description.

TOOL CALL · run_command

{
  "command": "python3 - <<'PY'\nfrom earthkit.data import from_source\nfrom earthkit.data.testing import earthkit_examples_file\ntry:\n    f = from_source(\"file\", earthkit_examples_file(\"temp_10.bufr\"))\n    print(\"Attempting to call to_pandas with filters={K}:\")\n    r = f.to_pandas(columns=[\"latitude\", \"longitude\"], filters={})\n    print(\"Success!\")\n    print(r)\nexcept Exception as e:\n    print(f\"Caught exception: {type(e).__name__}: {e}\")\nPY\n"
}

Result of run_command 382 characters

{
  "status": "ok",
  "stdout": "Attempting to call to_pandas with filters={K}:\nSuccess!\n   latitude  longitude\n0     67.37      26.63\n1     56.90       3.35\n2     58.87       5.67\n3     70.93      -8.67\n4     67.28      14.45\n5     63.70       9.60\n6     51.93     -10.25\n7     49.45      17.13\n8     48.25      16.37\n9     60.82      23.50\n",
  "stderr": "",
  "exit_code": 0
}

Turn 9at 159 s395 tokens out8,079 prompt tokens

Yes, it works when `filters={}` is passed.

The fix is to ensure `filters` is not `None` before passing it to `pdbufr.read_bufr`.

In `earthkit/data/readers/bufr.py`:
```python
    def to_pandas(self, columns=COLUMNS, filters=None, **kwargs):
        """Extracts BUFR data into an pandas DataFranme using :xref:`pdbufr`.
        ...
        """
        import pdbufr

        return pdbufr.read_bufr(self.path, columns=columns, filters=filters)
```

I will change it to:
```python
    def to_pandas(self, columns=COLUMNS, filters=None, **kwargs):
        """Extracts BUFR data into an pandas DataFranme using :xref:`pdbufr`.
        ...
        """
        import pdbufr

        if filters is None:
            filters = {}

        return pdbufr.read_bufr(self.path, columns=columns, filters=filters)
```
Wait, let me check if `pdbufr.read_bufr` accepts `filters=None` and if we should really be changing it to `{}`. The error `TypeError: 'NoneType' object is not iterable` in `pdbufr` clearly shows that it expects an iterable when it does `dict(filters)`.

Actually, a cleaner way might be `filters = filters or {}`.

Let's check if any other `to_pandas` implementation does something similar.
`earthkit/data/readers/grib/pandas.py` might be interesting.

TOOL CALL · read_file

{
  "filepath": "earthkit/data/readers/grib/pandas.py"
}

Result of read_file 1,567 characters

{
  "status": "ok",
  "filepath": "earthkit/data/readers/grib/pandas.py",
  "content": "# (C) Copyright 2020 ECMWF.\n#\n# This software is licensed under the terms of the Apache Licence Version 2.0\n# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.\n# In applying this licence, ECMWF does not waive the privileges and immunities\n# granted to it by virtue of its status as an intergovernmental organisation\n# nor does it submit to any jurisdiction.\n#\n\nimport logging\n\nLOG = logging.getLogger(__name__)\n\n\nclass PandasMixIn:\n    def to_pandas(self, latitude=None, longitude=None, **kwargs):\n        import numpy as np\n        import pandas as pd\n\n        def ident(x):\n            return x\n\n        filter = ident\n\n        def select_point(d):\n            idx = np.where((d[\"lat\"] == latitude) & (d[\"lon\"] == longitude))\n            return dict(lat=d[\"lat\"][idx], lon=d[\"lon\"][idx], value=d[\"value\"][idx])\n\n        if latitude is not None or longitude is not None:\n            filter = select_point\n\n        columns = (\"lat\", \"lon\", \"value\")\n        frames = []\n        for s in self:\n            df = pd.DataFrame.from_dict(\n                filter(dict(zip(columns, s.data(columns, flatten=True))))\n            )\n            df[\"datetime\"] = s.datetime()[\"valid_time\"]\n            for k, v in s.metadata(namespace=\"mars\").items():\n                df[k] = v\n            frames.append(df)\n        return pd.concat(frames)",
  "start_line": 1,
  "end_line": 42,
  "total_lines": 42,
  "is_truncated": false
}

Turn 10at 169 s144 tokens out8,962 prompt tokens

Not very similar.

Let's apply the fix in `earthkit/data/readers/bufr.py`.

TOOL CALL · edit_file

{
  "filepath": "earthkit/data/readers/bufr.py",
  "new_string": "        import pdbufr\\n\\n        if filters is None:\\n            filters = {}\\n\\n        return pdbufr.read_bufr(self.path, columns=columns, filters=filters)\\n`,old_string:"
}