ROLLOUT 0 · coady/multimethod
coady__multimethod-26
Not solved
453 stotal time
27tool calls
27model calls
6,169tokens generated
230,528prompt tokens read
Empty agent patch
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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 4,279 characters
You are evaluating a software engineering task for repository coady/multimethod.
Problem Statement:
TypeError when one of the type hints is type or another metaclass
Using `type` (or any other subclass of `type`, e.g. a custom metaclass) as the type hint for one of the parameters of a function of a multimethod makes the dispatch process raise a `TypeError` when calling `type.mro()` (which expects the type object as an argument).
## Example
```python
@multimethod
def f(x: type):
print("success")
```
### Expected
```python
>>> f(int)
success
```
### Actual
```python
>>> f(int)
TypeError: unbound method type.mro() needs an argument
```
Traceback:
<details>
```
Traceback (most recent call last):
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\IPython\core\interactiveshell.py", line 3418, in run_code
exec(code_obj, self.user_global_ns, self.user_ns)
File "<ipython-input-34-0374cd2152b2>", line 1, in <module>
f(int)
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 184, in __call__
return self[tuple(map(self.get_type, args))](*args, **kwargs)
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 184, in __call__
return self[tuple(map(self.get_type, args))](*args, **kwargs)
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 174, in __missing__
groups = groupby(signature(types).__sub__, self.parents(types))
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 17, in groupby
groups[func(value)].append(value)
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 104, in __sub__
return tuple(mro.index(cls if cls in mro else object) for mro, cls in zip(mros, other))
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 104, in <genexpr>
return tuple(mro.index(cls if cls in mro else object) for mro, cls in zip(mros, other))
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 103, in <genexpr>
mros = (subclass.mro() for subclass in self)
TypeError: unbound method type.mro() needs an argument
```
</details>
## Cause
Methods of metaclasses like `type`, e.g. `.mro()` expect an explicit first argument which is the actual type object being used.
## 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.txt
./MANIFEST.in
./Makefile
./README.md
./docs
./mkdocs.yml
./multimethod
./multimethod/__init__.py
./multimethod/py.typed
./pyproject.toml
./setup.cfg
./setup.py
./tests
```
Turn 1at 23 s342 tokens out3,371 prompt tokens
The user is reporting a `TypeError` when using `type` or a metaclass as a type hint in a multimethod.
The traceback points to `multimethod/__init__.py`, specifically in the `__sub__` method of a class (likely `Signature` or something similar) where `subclass.mro()` is called.
Wait, looking at the traceback:
```
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 103, in <genexpr>
mros = (subclass.mro() for subclass in self)
TypeError: unbound method type.mro() needs an argument
```
If `subclass` is `type`, then `type.mro()` is being called as an unbound method.
In Python, `type.mro(some_class)` works, but `type.mro()` doesn't because it's a method on the metaclass.
Normally, if `subclass` is a class, `subclass.mro()` works because `subclass` is an instance of `type`.
But if `subclass` is actually the class `type` itself, then `subclass.mro()` is equivalent to `type.mro()`.
Let's examine the code in `multimethod/__init__.py`.
TOOL CALL · run_command
{
"command": "grep -rn --include=\"*.py\" \"mro()\" ."
}Result of run_command 116 characters
{
"status": "ok",
"stdout": "./multimethod/__init__.py:102: mro = subclass.mro()\n",
"stderr": "",
"exit_code": 0
}Generated tokens 342 tokens · stopped: STOP
<|channel>thought
The user is reporting a `TypeError` when using `type` or a metaclass as a type hint in a multimethod.
The traceback points to `multimethod/__init__.py`, specifically in the `__sub__` method of a class (likely `Signature` or something similar) where `subclass.mro()` is called.
Wait, looking at the traceback:
```
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 103, in <genexpr>
mros = (subclass.mro() for subclass in self)
TypeError: unbound method type.mro() needs an argument
```
If `subclass` is `type`, then `type.mro()` is being called as an unbound method.
In Python, `type.mro(some_class)` works, but `type.mro()` doesn't because it's a method on the metaclass.
Normally, if `subclass` is a class, `subclass.mro()` works because `subclass` is an instance of `type`.
But if `subclass` is actually the class `type` itself, then `subclass.mro()` is equivalent to `type.mro()`.
Let's examine the code in `multimethod/__init__.py`.<channel|><|tool_call>call:run_command{command:<|"|>grep -rn --include="*.py" "mro()" .<|"|>}<tool_call|><|tool_response>
Turn 2at 29 s85 tokens out3,774 prompt tokens
Wait, the grep says line 102. The traceback says 103 (likely difference in versions or line endings). Let's read `multimethod/__init__.py` around line 102.
TOOL CALL · read_file
{
"end_line": 120,
"filepath": "multimethod/__init__.py",
"start_line": 80
}Result of read_file 1,619 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": " nargs = len(self.__args__)\n if self.__origin__ is tuple and self.__args__[-1:] == (Ellipsis,):\n nargs -= 1\n args = args[:nargs]\n return ( # check args first to avoid a recursion error in ABCMeta\n len(args) == nargs\n and issubclass(origin, self.__origin__)\n and all(map(issubclass, args, self.__args__))\n )\n\n @classmethod\n def subcheck(cls, tp: type) -> bool:\n \"\"\"Return whether type requires checking subscripts using `get_type`.\"\"\"\n return isinstance(tp, cls) and (\n tp.__origin__ is not Union or any(map(cls.subcheck, tp.__args__))\n )\n\n\ndef distance(cls, subclass: type) -> int:\n \"\"\"Return estimated distance between classes for tie-breaking.\"\"\"\n if getattr(cls, '__origin__', None) is typing.Union:\n return min(distance(arg, subclass) for arg in cls.__args__)\n mro = subclass.mro()\n return mro.index(cls if cls in mro else object)\n\n\nclass signature(tuple):\n \"\"\"A tuple of types that supports partial ordering.\"\"\"\n\n parents: set\n\n def __new__(cls, types: Iterable):\n return tuple.__new__(cls, map(subtype, types))\n\n def __le__(self, other) -> bool:\n return len(self) <= len(other) and all(map(issubclass, other, self))\n\n def __lt__(self, other) -> bool:\n return self != other and self <= other\n\n def __sub__(self, other) -> tuple:",
"start_line": 80,
"end_line": 120,
"total_lines": 309,
"is_truncated": false
}Generated tokens 85 tokens · stopped: STOP
Wait, the grep says line 102. The traceback says 103 (likely difference in versions or line endings).
Let's read `multimethod/__init__.py` around line 102.<channel|><|tool_call>call:read_file{filepath:<|"|>multimethod/__init__.py<|"|>,start_line:80,end_line:120}<tool_call|><|tool_response>
Turn 3at 40 s223 tokens out4,367 prompt tokens
Wait, the traceback said line 103/104.
Let's look at `distance` function first:
```python
def distance(cls, subclass: type) -> int:
"""Return estimated distance between classes for tie-breaking."""
if getattr(cls, '__origin__', None) is typing.Union:
return min(distance(arg, subclass) for arg in cls.__args__)
mro = subclass.mro()
return mro.index(cls if cls in mro else object)
```
If `subclass` is `type`, then `subclass.mro()` is `type.mro()`, which fails.
Now let's look at `signature.__sub__`:
The `read_file` ended at line 120. Let's read further.
TOOL CALL · read_file
{
"end_line": 130,
"filepath": "multimethod/__init__.py",
"start_line": 121
}Result of read_file 413 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": " \"\"\"Return relative distances, assuming self >= other.\"\"\"\n return tuple(map(distance, other, self))\n\n\nclass multimethod(dict):\n \"\"\"A callable directed acyclic graph of methods.\"\"\"\n\n pending: set\n\n def __new__(cls, func):",
"start_line": 121,
"end_line": 130,
"total_lines": 309,
"is_truncated": false
}Generated tokens 223 tokens · stopped: STOP
Wait, the traceback said line 103/104.
Let's look at `distance` function first:
```python
def distance(cls, subclass: type) -> int:
"""Return estimated distance between classes for tie-breaking."""
if getattr(cls, '__origin__', None) is typing.Union:
return min(distance(arg, subclass) for arg in cls.__args__)
mro = subclass.mro()
return mro.index(cls if cls in mro else object)
```
If `subclass` is `type`, then `subclass.mro()` is `type.mro()`, which fails.
Now let's look at `signature.__sub__`:
The `read_file` ended at line 120. Let's read further.
<channel|><|tool_call>call:read_file{end_line:130,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:121}<tool_call|><|tool_response>
Turn 4at 102 s1,103 tokens out4,740 prompt tokens
In `signature.__sub__`:
```python
def __sub__(self, other) -> tuple:
"""Return relative distances, assuming self >= other."""
return tuple(map(distance, other, self))
```
Wait, I missed something. The traceback says:
```
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 104, in __sub__
return tuple(mro.index(cls if cls in mro else object) for mro, cls in zip(mros, other))
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 104, in <genexpr>
return tuple(mro.index(cls if cls in mro else object) for mro, cls in zip(mros, other))
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 103, in <genexpr>
mros = (subclass.mro() for subclass in self)
```
This looks DIFFERENT from what I see in `multimethod/__init__.py` in my current environment.
Let me check the line numbers again.
In my `read_file`:
Line 102 is `mro = subclass.mro()` inside `distance(cls, subclass: type)`.
Line 119-120 is `def __sub__(self, other) -> tuple:` and `"""Return relative distances, assuming self >= other."""`.
Wait, the traceback provided in the issue might be from an older version of the library, or I'm misreading the `read_file` output.
Let's check the file content again.
```python
def distance(cls, subclass: type) -> int:
"""Return estimated distance between classes for tie-breaking."""
if getattr(cls, '__origin__', None) is typing.Union:
return min(distance(arg, subclass) for arg in cls.__args__)
mro = subclass.mro()
return mro.index(cls if cls in mro else object)
```
The line `mro = subclass.mro()` is indeed where the crash happens if `subclass` is `type`.
Wait, if `subclass` is `type`, calling `subclass.mro()` is equivalent to `type.mro()`.
In Python:
```python
>>> type.mro()
TypeError: unbound method type.mro() needs an argument
>>> int.mro()
[<class 'int'>, <class 'object'>]
```
Wait, why does `int.mro()` work? Because `int` is an instance of `type`.
If `subclass` is `type`, it's an instance of `type` (because `type` is its own type).
Wait:
```python
>>> type.mro()
TypeError: unbound method type.mro() needs an argument
```
Yes, because `type.mro` is a method on the metaclass `type`. To get the MRO of `type`, you should call `type.mro(type)`.
Actually, for any class `C`, `C.mro()` is a shorthand for `type.mro(C)`.
If `C` is `type`, then `type.mro()` is called, but `type.mro` is a function that expects one argument (the class whose MRO it should return).
Since `multimethod` is using `subclass.mro()`, it's calling the method on the object `subclass`.
If `subclass` is `int`, `int.mro()` is called.
If `subclass` is `type`, `type.mro()` is called.
To fix this, we should use `type.mro(subclass)` or check if it's `type`.
Wait, `type.mro(subclass)` should work for any class.
Let's test:
```python
>>> type.mro(int)
[<class 'int'>, <class 'object'>]
>>> type.mro(type)
[<class 'type'>, <class 'object'>]
```
Yes, that works!
Let's reproduce this with a script.
TOOL CALL · run_command
{
"command": "python3 - <<'PY'\nfrom multimethod import multimethod\n\n@multimethod\ndef f(x: type):\n print(\"success\")\n\ntry:\n f(int)\nexcept Exception as e:\n import traceback\n traceback.print_exc()\nPY\n"
}Result of run_command 69 characters
{
"status": "ok",
"stdout": "success\n",
"stderr": "",
"exit_code": 0
}Generated tokens 1,103 tokens · stopped: STOP
In `signature.__sub__`:
```python
def __sub__(self, other) -> tuple:
"""Return relative distances, assuming self >= other."""
return tuple(map(distance, other, self))
```
Wait, I missed something. The traceback says:
```
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 104, in __sub__
return tuple(mro.index(cls if cls in mro else object) for mro, cls in zip(mros, other))
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 104, in <genexpr>
return tuple(mro.index(cls if cls in mro else object) for mro, cls in zip(mros, other))
File "C:\Users\Paolo\Code\JB-PycharmProjects\LoveLetter\venv\lib\site-packages\multimethod\__init__.py", line 103, in <genexpr>
mros = (subclass.mro() for subclass in self)
```
This looks DIFFERENT from what I see in `multimethod/__init__.py` in my current environment.
Let me check the line numbers again.
In my `read_file`:
Line 102 is `mro = subclass.mro()` inside `distance(cls, subclass: type)`.
Line 119-120 is `def __sub__(self, other) -> tuple:` and `"""Return relative distances, assuming self >= other."""`.
Wait, the traceback provided in the issue might be from an older version of the library, or I'm misreading the `read_file` output.
Let's check the file content again.
```python
def distance(cls, subclass: type) -> int:
"""Return estimated distance between classes for tie-breaking."""
if getattr(cls, '__origin__', None) is typing.Union:
return min(distance(arg, subclass) for arg in cls.__args__)
mro = subclass.mro()
return mro.index(cls if cls in mro else object)
```
The line `mro = subclass.mro()` is indeed where the crash happens if `subclass` is `type`.
Wait, if `subclass` is `type`, calling `subclass.mro()` is equivalent to `type.mro()`.
In Python:
```python
>>> type.mro()
TypeError: unbound method type.mro() needs an argument
>>> int.mro()
[<class 'int'>, <class 'object'>]
```
Wait, why does `int.mro()` work? Because `int` is an instance of `type`.
If `subclass` is `type`, it's an instance of `type` (because `type` is its own type).
Wait:
```python
>>> type.mro()
TypeError: unbound method type.mro() needs an argument
```
Yes, because `type.mro` is a method on the metaclass `type`. To get the MRO of `type`, you should call `type.mro(type)`.
Actually, for any class `C`, `C.mro()` is a shorthand for `type.mro(C)`.
If `C` is `type`, then `type.mro()` is called, but `type.mro` is a function that expects one argument (the class whose MRO it should return).
Since `multimethod` is using `subclass.mro()`, it's calling the method on the object `subclass`.
If `subclass` is `int`, `int.mro()` is called.
If `subclass` is `type`, `type.mro()` is called.
To fix this, we should use `type.mro(subclass)` or check if it's `type`.
Wait, `type.mro(subclass)` should work for any class.
Let's test:
```python
>>> type.mro(int)
[<class 'int'>, <class 'object'>]
>>> type.mro(type)
[<class 'type'>, <class 'object'>]
```
Yes, that works!
Let's reproduce this with a script.
<channel|><|tool_call>call:run_command{command:<|"|>python3 - <<'PY'
from multimethod import multimethod
@multimethod
def f(x: type):
print("success")
try:
f(int)
except Exception as e:
import traceback
traceback.print_exc()
PY
<|"|>}<tool_call|><|tool_response>
Turn 5at 167 s1,019 tokens out5,884 prompt tokens
Wait, it worked?
The example in the issue says:
```python
@multimethod
def f(x: type):
print("success")
f(int)
```
Expected: `success`
Actual: `TypeError: unbound method type.mro() needs an argument`
Why did it work for me?
Maybe the version in `/workspace` is already fixed? Or maybe my reproduction is too simple?
Wait, the error happens during *dispatch* when it evaluates candidates.
Let's look at the `distance` function again.
```python
def distance(cls, subclass: type) -> int:
"""Return estimated distance between classes for tie-breaking."""
if getattr(cls, '__origin__', None) is typing.Union:
return min(distance(arg, subclass) for arg in cls.__args__)
mro = subclass.mro()
return mro.index(cls if cls in mro else object)
```
This function is called by `signature.__sub__`.
And `signature.__sub__` is called by `multimethod.__missing__` during dispatch.
Wait, if I have only one method `f(x: type)`, then it's the only candidate.
Does it call `distance` when there's only one candidate?
Let's look at `multimethod.__call__`.
The traceback says:
```
File ".../multimethod/__init__.py", line 184, in __call__
return self[tuple(map(self.get_type, args))](*args, **kwargs)
File ".../multimmethod/__init__.py", line 184, in __call__ (duplicate line in traceback?)
return self[tuple(map(self.get_type, args))](*args, **kwargs)
File ".../multimethod/__init__.py", line 174, in __missing__
groups = groupby(signature(types).__sub__, self.parents(types))
```
It seems `__missing__` is called when the exact match is not found.
In my reproduction:
```python
@multimethod
def f(x: type):
print("success")
f(int)
```
`self.get_type(int)` is `type`.
The candidates are stored in the `multimethod` object (which is a `dict`).
The keys are `signature` objects.
For `f(x: type)`, the key is `signature((type,))`.
So `self[(type,)]` is called. This is an exact match!
No `__missing__` is called.
The error happens when there is NO exact match, and it needs to find the best candidate.
So I need at least two candidates, or a candidate that isn't an exact match.
Example 2:
```python
@multimethod
def f(x: object):
print("object")
@multimethod
def f(x: type):
print("type")
f(int)
```
Here, `f(int)` where `int` is a type.
The exact type of `int` is `type`.
Wait, `self.get_type(int)` will return `type`.
If I have `f(x: type)`, then `self[(type,)]` will be an exact match.
What if I have:
```python
@multimethod
def f(x: object):
print("object")
f(int)
```
`self.get_type(int)` is `type`.
`self[(type,)]` does not exist.
So it calls `__missing__((type,))`.
Then it calls `signature((type,)).__sub__(other)`.
Inside `__sub__`, it calls `distance(cls, subclass)`.
`subclass` will be the type of the argument, which is `type`.
`distance(object, type)` will be called.
Inside `distance(object, type)`:
`subclass` is `type`.
`mro = subclass.mro()` -> `type.mro()` -> BOOM!
Let's reproduce this.
TOOL CALL · run_command
{
"command": "python3 - <<'PY'\nfrom multimethod import multimethod\n\n@multimethod\ndef f(x: object):\n print(\"object\")\n\ntry:\n f(int)\nexcept Exception as e:\n import traceback\n traceback.print_exc()\nPY\n"
}Result of run_command 68 characters
{
"status": "ok",
"stdout": "object\n",
"stderr": "",
"exit_code": 0
}Generated tokens 1,019 tokens · stopped: STOP
Wait, it worked?
The example in the issue says:
```python
@multimethod
def f(x: type):
print("success")
f(int)
```
Expected: `success`
Actual: `TypeError: unbound method type.mro() needs an argument`
Why did it work for me?
Maybe the version in `/workspace` is already fixed? Or maybe my reproduction is too simple?
Wait, the error happens during *dispatch* when it evaluates candidates.
Let's look at the `distance` function again.
```python
def distance(cls, subclass: type) -> int:
"""Return estimated distance between classes for tie-breaking."""
if getattr(cls, '__origin__', None) is typing.Union:
return min(distance(arg, subclass) for arg in cls.__args__)
mro = subclass.mro()
return mro.index(cls if cls in mro else object)
```
This function is called by `signature.__sub__`.
And `signature.__sub__` is called by `multimethod.__missing__` during dispatch.
Wait, if I have only one method `f(x: type)`, then it's the only candidate.
Does it call `distance` when there's only one candidate?
Let's look at `multimethod.__call__`.
The traceback says:
```
File ".../multimethod/__init__.py", line 184, in __call__
return self[tuple(map(self.get_type, args))](*args, **kwargs)
File ".../multimmethod/__init__.py", line 184, in __call__ (duplicate line in traceback?)
return self[tuple(map(self.get_type, args))](*args, **kwargs)
File ".../multimethod/__init__.py", line 174, in __missing__
groups = groupby(signature(types).__sub__, self.parents(types))
```
It seems `__missing__` is called when the exact match is not found.
In my reproduction:
```python
@multimethod
def f(x: type):
print("success")
f(int)
```
`self.get_type(int)` is `type`.
The candidates are stored in the `multimethod` object (which is a `dict`).
The keys are `signature` objects.
For `f(x: type)`, the key is `signature((type,))`.
So `self[(type,)]` is called. This is an exact match!
No `__missing__` is called.
The error happens when there is NO exact match, and it needs to find the best candidate.
So I need at least two candidates, or a candidate that isn't an exact match.
Example 2:
```python
@multimethod
def f(x: object):
print("object")
@multimethod
def f(x: type):
print("type")
f(int)
```
Here, `f(int)` where `int` is a type.
The exact type of `int` is `type`.
Wait, `self.get_type(int)` will return `type`.
If I have `f(x: type)`, then `self[(type,)]` will be an exact match.
What if I have:
```python
@multimethod
def f(x: object):
print("object")
f(int)
```
`self.get_type(int)` is `type`.
`self[(type,)]` does not exist.
So it calls `__missing__((type,))`.
Then it calls `signature((type,)).__sub__(other)`.
Inside `__sub__`, it calls `distance(cls, subclass)`.
`subclass` will be the type of the argument, which is `type`.
`distance(object, type)` will be called.
Inside `distance(object, type)`:
`subclass` is `type`.
`mro = subclass.mro()` -> `type.mro()` -> BOOM!
Let's reproduce this.
<channel|><|tool_call>call:run_command{command:<|"|>python3 - <<'PY'
from multimethod import multimethod
@multimethod
def f(x: object):
print("object")
try:
f(int)
except Exception as e:
import traceback
traceback.print_exc()
PY
<|"|>}<tool_call|><|tool_response>
Turn 6at 171 s76 tokens out6,944 prompt tokens
Wait, it still worked? Why? Maybe `self.get_type(int)` is NOT `type`? Let's check what `get_type` does.
TOOL CALL · read_file
{
"end_line": 100,
"filepath": "multimethod/__init__.py",
"start_line": 50
}Result of read_file 2,348 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": " return object\n tp = typing.Union[tp.__constraints__]\n origin = getattr(tp, '__extra__', getattr(tp, '__origin__', tp))\n args = tuple(map(cls, getattr(tp, '__args__', None) or args))\n if set(args) <= {object} and not (origin is tuple and args):\n return origin\n bases = (origin,) if type(origin) is type else ()\n namespace = {'__origin__': origin, '__args__': args}\n return type.__new__(cls, str(tp), bases, namespace)\n\n def __init__(self, tp, *args):\n if isinstance(self.__origin__, abc.ABCMeta):\n self.__origin__.register(self)\n\n def __getstate__(self) -> tuple:\n return self.__origin__, self.__args__\n\n def __eq__(self, other) -> bool:\n return isinstance(other, subtype) and self.__getstate__() == other.__getstate__()\n\n def __hash__(self) -> int:\n return hash(self.__getstate__())\n\n def __subclasscheck__(self, subclass: type) -> bool:\n origin = getattr(subclass, '__extra__', getattr(subclass, '__origin__', subclass))\n args = getattr(subclass, '__args__', ())\n if origin is typing.Union:\n return all(issubclass(cls, self) for cls in args)\n if self.__origin__ is typing.Union:\n return issubclass(subclass, self.__args__)\n nargs = len(self.__args__)\n if self.__origin__ is tuple and self.__args__[-1:] == (Ellipsis,):\n nargs -= 1\n args = args[:nargs]\n return ( # check args first to avoid a recursion error in ABCMeta\n len(args) == nargs\n and issubclass(origin, self.__origin__)\n and all(map(issubclass, args, self.__args__))\n )\n\n @classmethod\n def subcheck(cls, tp: type) -> bool:\n \"\"\"Return whether type requires checking subscripts using `get_type`.\"\"\"\n return isinstance(tp, cls) and (\n tp.__origin__ is not Union or any(map(cls.subcheck, tp.__args__))\n )\n\n\ndef distance(cls, subclass: type) -> int:\n \"\"\"Return estimated distance between classes for tie-breaking.\"\"\"\n if getattr(cls, '__origin__', None) is typing.Union:",
"start_line": 50,
"end_line": 100,
"total_lines": 309,
"is_truncated": false
}Generated tokens 76 tokens · stopped: STOP
Wait, it still worked? Why?
Maybe `self.get_type(int)` is NOT `type`?
Let's check what `get_type` does.
<channel|><|tool_call>call:read_file{end_line:100,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:50}<tool_call|><|tool_response>
Turn 7at 175 s60 tokens out7,713 prompt tokens
I need to see `get_type`. It's probably a method of `multimethod`.
TOOL CALL · read_file
{
"end_line": 180,
"filepath": "multimethod/__init__.py",
"start_line": 150
}Result of read_file 1,405 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": " return overload.register(self, *args) # type: ignore\n return lambda func: self.__setitem__(args, func) or func\n\n def __get__(self, instance, owner):\n return self if instance is None else types.MethodType(self, instance)\n\n def parents(self, types: tuple) -> set:\n \"\"\"Find immediate parents of potential key.\"\"\"\n parents = {key for key in self if isinstance(key, signature) and key < types}\n return parents - {ancestor for parent in parents for ancestor in parent.parents}\n\n def clean(self):\n \"\"\"Empty the cache.\"\"\"\n for key in list(self):\n if not isinstance(key, signature):\n super().__delitem__(key)\n\n def copy(self):\n \"\"\"Return a new multimethod with the same methods.\"\"\"\n other = dict.__new__(type(self))\n other.update(self)\n return other\n\n def __setitem__(self, types: tuple, func: Callable):\n self.clean()\n types = signature(types)\n parents = types.parents = self.parents(types)\n for key in self:\n if types < key and (not parents or parents & key.parents):\n key.parents -= parents\n key.parents.add(types)",
"start_line": 150,
"end_line": 180,
"total_lines": 309,
"is_truncated": false
}Generated tokens 60 tokens · stopped: STOP
I need to see `get_type`. It's probably a method of `multimethod`.
<channel|><|tool_call>call:read_file{end_line:180,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:150}<tool_call|><|tool_response>
Turn 8at 178 s52 tokens out8,173 prompt tokens
I still don't see `get_type`. Let me search for `def get_type`.
TOOL CALL · run_command
{
"command": "grep -n \"def get_type\" multimethod/__init__.py"
}Result of run_command 202 characters
{
"status": "ok",
"stdout": "21:def get_types(func: Callable) -> tuple:\n246:def get_type(arg: tuple):\n252:def get_type(arg: Mapping):\n258:def get_type(arg: Iterable):\n",
"stderr": "",
"exit_code": 0
}Generated tokens 52 tokens · stopped: STOP
I still don't see `get_type`. Let me search for `def get_type`.
<channel|><|tool_call>call:run_command{command:<|"|>grep -n "def get_type" multimethod/__init__.py<|"|>}<tool_call|><|tool_response>
Turn 9at 191 s188 tokens out8,321 prompt tokens
Wait, there are several `get_type` definitions. Python allows overwriting them if they are in the same scope? No, they are probably in different scopes or it's a mistake in my grep search. Actually, they look like they are redefining the same name. Or maybe they are overloaded? No, Python doesn't work that way. Wait, look at the grep output again: ``` 246:def get_type(arg: tuple): 252:def get_type(arg: Mapping): 258:def get_type(arg: Iterable): ``` This is very strange. Let's read lines 240 to the end of `multimethod/__init__.py`.
TOOL CALL · read_file
{
"filepath": "multimethod/__init__.py",
"start_line": 240
}Result of read_file 2,645 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": "get_type.__doc__ = \"\"\"Return a generic `subtype` which checks subscripts.\"\"\"\nfor atomic in (Iterator, str, bytes):\n get_type[(atomic,)] = type\n\n\n@multimethod # type: ignore[no-redef]\ndef get_type(arg: tuple):\n \"\"\"Return generic type checking all values.\"\"\"\n return subtype(type(arg), *map(get_type, arg))\n\n\n@multimethod # type: ignore[no-redef]\ndef get_type(arg: Mapping):\n \"\"\"Return generic type checking first item.\"\"\"\n return subtype(type(arg), *map(get_type, next(iter(arg.items()), ())))\n\n\n@multimethod # type: ignore[no-redef]\ndef get_type(arg: Iterable):\n \"\"\"Return generic type checking first value.\"\"\"\n return subtype(type(arg), *map(get_type, itertools.islice(arg, 1)))\n\n\ndef isa(*types: type) -> Callable:\n \"\"\"Partially bound `isinstance`.\"\"\"\n return lambda arg: isinstance(arg, types)\n\n\nclass overload(collections.OrderedDict):\n \"\"\"Ordered functions which dispatch based on their annotated predicates.\"\"\"\n\n __get__ = multimethod.__get__\n\n def __new__(cls, func):\n namespace = inspect.currentframe().f_back.f_locals\n self = functools.update_wrapper(super().__new__(cls), func)\n return namespace.get(func.__name__, self)\n\n def __init__(self, func: Callable):\n self[inspect.signature(func)] = func\n\n def __call__(self, *args, **kwargs):\n \"\"\"Dispatch to first matching function.\"\"\"\n for sig, func in reversed(self.items()):\n arguments = sig.bind(*args, **kwargs).arguments\n if all(\n param.annotation(arguments[name])\n for name, param in sig.parameters.items()\n if param.annotation is not param.empty\n ):\n return func(*args, **kwargs)\n raise DispatchError(\"No matching functions found\")\n\n def register(self, func: Callable) -> Callable:\n \"\"\"Decorator for registering a function.\"\"\"\n self.__init__(func) # type: ignore\n return self if self.__name__ == func.__name__ else func # type: ignore\n\n\nclass multimeta(type):\n \"\"\"Convert all callables in namespace to multimethods.\"\"\"\n\n class __prepare__(dict):\n def __init__(*args):\n pass\n\n def __setitem__(self, key, value):\n if callable(value):\n value = getattr(self.get(key), 'register', multimethod)(value)\n super().__setitem__(key, value)",
"start_line": 240,
"end_line": 309,
"total_lines": 309,
"is_truncated": false
}Generated tokens 188 tokens · stopped: STOP
Wait, there are several `get_type` definitions. Python allows overwriting them if they are in the same scope? No, they are probably in different scopes or it's a mistake in my grep search.
Actually, they look like they are redefining the same name. Or maybe they are overloaded? No, Python doesn't work that way.
Wait, look at the grep output again:
```
246:def get_type(arg: tuple):
252:def get_type(arg: Mapping):
258:def get_type(arg: Iterable):
```
This is very strange. Let's read lines 240 to the end of `multimethod/__init__.py`.
<channel|><|tool_call>call:read_file{filepath:<|"|>multimethod/__init__.py<|"|>,start_line:240}<tool_call|><|tool_response>
Turn 10at 215 s314 tokens out9,297 prompt tokens
Ah, `get_type` is itself a `multimethod`!
```python
@multimethod # type: ignore[no-redef]
def get_type(arg: tuple):
...
```
So when `f(int)` is called, and `self.get_type(int)` is called, it uses `get_type`'s dispatch mechanism.
Wait, what is the type hint for `get_type(arg: tuple)`? It's `tuple`.
When we call `get_type(int)`, `int` is NOT a tuple.
Is there any other `get_type`?
No, only `tuple`, `Mapping`, `Iterable`.
Wait, what happens if `get_type` is called with something that doesn't match any of these?
It will call `__missing__` of the `get_type` multimethod.
Wait, `get_type` is a `multimethod` instance.
If it doesn't find an exact match, it goes to `__missing__`.
But in my tests, `f(int)` worked.
Let's test what `get_type(int)` actually returns.
TOOL CALL · run_command
{
"command": "python3 - <<'PY'\nfrom multimethod import get_type\nprint(f\"get_type(int) = {get_type(int)}\")\nPY\n"
}Result of run_command 92 characters
{
"status": "ok",
"stdout": "get_type(int) = <class 'type'>\n",
"stderr": "",
"exit_code": 0
}Generated tokens 314 tokens · stopped: STOP
Ah, `get_type` is itself a `multimethod`!
```python
@multimethod # type: ignore[no-redef]
def get_type(arg: tuple):
...
```
So when `f(int)` is called, and `self.get_type(int)` is called, it uses `get_type`'s dispatch mechanism.
Wait, what is the type hint for `get_type(arg: tuple)`? It's `tuple`.
When we call `get_type(int)`, `int` is NOT a tuple.
Is there any other `get_type`?
No, only `tuple`, `Mapping`, `Iterable`.
Wait, what happens if `get_type` is called with something that doesn't match any of these?
It will call `__missing__` of the `get_type` multimethod.
Wait, `get_type` is a `multimethod` instance.
If it doesn't find an exact match, it goes to `__missing__`.
But in my tests, `f(int)` worked.
Let's test what `get_type(int)` actually returns.<channel|><|tool_call>call:run_command{command:<|"|>python3 - <<'PY'
from multimethod import get_type
print(f"get_type(int) = {get_type(int)}")
PY
<|"|>}<tool_call|><|tool_response>
Turn 11at 225 s120 tokens out9,664 prompt tokens
Wait, `get_type(int)` returns `<class 'type'>`? How? `int` is not a tuple, Mapping or Iterable. Let's look at the definitions of `get_type` in `multimethod/__init__.py` again. Actually, I missed some parts of `multimethod/__init__.py`. Let me read it from the beginning.
TOOL CALL · read_file
{
"end_line": 100,
"filepath": "multimethod/__init__.py",
"start_line": 1
}Result of read_file 3,908 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": "import abc\nimport collections\nimport functools\nimport inspect\nimport itertools\nimport types\nimport typing\nfrom typing import Callable, Iterable, Iterator, Mapping, Union\n\n__version__ = '1.4'\n\n\ndef groupby(func: Callable, values: Iterable) -> dict:\n \"\"\"Return mapping of key function to values.\"\"\"\n groups = collections.defaultdict(list) # type: dict\n for value in values:\n groups[func(value)].append(value)\n return groups\n\n\ndef get_types(func: Callable) -> tuple:\n \"\"\"Return evaluated type hints for positional required parameters in order.\"\"\"\n if not hasattr(func, '__annotations__'):\n return ()\n type_hints = typing.get_type_hints(func)\n positionals = {inspect.Parameter.POSITIONAL_ONLY, inspect.Parameter.POSITIONAL_OR_KEYWORD}\n annotations = [\n type_hints.get(param.name, object)\n for param in inspect.signature(func).parameters.values()\n if param.default is param.empty and param.kind in positionals\n ] # missing annotations are padded with `object`, but trailing objects are unnecessary\n return tuple(itertools.dropwhile(lambda cls: cls is object, reversed(annotations)))[::-1]\n\n\nclass DispatchError(TypeError):\n pass\n\n\nclass subtype(type):\n \"\"\"A normalized generic type which checks subscripts.\"\"\"\n\n __origin__: type\n __args__: tuple\n\n def __new__(cls, tp, *args):\n if tp is typing.Any:\n return object\n if isinstance(tp, typing.TypeVar):\n if not tp.__constraints__:\n return object\n tp = typing.Union[tp.__constraints__]\n origin = getattr(tp, '__extra__', getattr(tp, '__origin__', tp))\n args = tuple(map(cls, getattr(tp, '__args__', None) or args))\n if set(args) <= {object} and not (origin is tuple and args):\n return origin\n bases = (origin,) if type(origin) is type else ()\n namespace = {'__origin__': origin, '__args__': args}\n return type.__new__(cls, str(tp), bases, namespace)\n\n def __init__(self, tp, *args):\n if isinstance(self.__origin__, abc.ABCMeta):\n self.__origin__.register(self)\n\n def __getstate__(self) -> tuple:\n return self.__origin__, self.__args__\n\n def __eq__(self, other) -> bool:\n return isinstance(other, subtype) and self.__getstate__() == other.__getstate__()\n\n def __hash__(self) -> int:\n return hash(self.__getstate__())\n\n def __subclasscheck__(self, subclass: type) -> bool:\n origin = getattr(subclass, '__extra__', getattr(subclass, '__origin__', subclass))\n args = getattr(subclass, '__args__', ())\n if origin is typing.Union:\n return all(issubclass(cls, self) for cls in args)\n if self.__origin__ is typing.Union:\n return issubclass(subclass, self.__args__)\n nargs = len(self.__args__)\n if self.__origin__ is tuple and self.__args__[-1:] == (Ellipsis,):\n nargs -= 1\n args = args[:nargs]\n return ( # check args first to avoid a recursion error in ABCMeta\n len(args) == nargs\n and issubclass(origin, self.__origin__)\n and all(map(issubclass, args, self.__args__))\n )\n\n @classmethod\n def subcheck(cls, tp: type) -> bool:\n \"\"\"Return whether type requires checking subscripts using `get_type`.\"\"\"\n return isinstance(tp, cls) and (\n tp.__origin__ is not Union or any(map(cls.subcheck, tp.__args__))\n )\n\n\ndef distance(cls, subclass: type) -> int:\n \"\"\"Return estimated distance between classes for tie-breaking.\"\"\"\n if getattr(cls, '__origin__', None) is typing.Union:",
"start_line": 1,
"end_line": 100,
"total_lines": 309,
"is_truncated": false
}Generated tokens 120 tokens · stopped: STOP
Wait, `get_type(int)` returns `<class 'type'>`?
How? `int` is not a tuple, Mapping or Iterable.
Let's look at the definitions of `get_type` in `multimethod/__init__.py` again.
Actually, I missed some parts of `multimethod/__init__.py`. Let me read it from the beginning.
<channel|><|tool_call>call:read_file{end_line:100,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:1}<tool_call|><|tool_response>
Turn 12at 233 s143 tokens out10,902 prompt tokens
Wait, I see it now!
I missed this part in the previous `read_file`:
```python
def __call__(self, args, kwargs):
# ... (trimmed)
return self[tuple(map(self.get_type, args))](*args, **kwargs)
```
I need to see the `multimethod.__call__` implementation.
Let's read `multimethod/__init__.py` from line 170.
TOOL CALL · read_file
{
"end_line": 190,
"filepath": "multimethod/__init__.py",
"start_line": 170
}Result of read_file 919 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": " other.update(self)\n return other\n\n def __setitem__(self, types: tuple, func: Callable):\n self.clean()\n types = signature(types)\n parents = types.parents = self.parents(types)\n for key in self:\n if types < key and (not parents or parents & key.parents):\n key.parents -= parents\n key.parents.add(types)\n if any(map(subtype.subcheck, types)):\n self.get_type = get_type # switch to slower generic type checker\n super().__setitem__(types, func)\n self.__doc__ = self.docstring\n\n def __delitem__(self, types: tuple):\n self.clean()\n super().__delitem__(types)\n for key in self:\n if types in key.parents:",
"start_line": 170,
"end_line": 190,
"total_lines": 309,
"is_truncated": false
}Generated tokens 143 tokens · stopped: STOP
Wait, I see it now!
I missed this part in the previous `read_file`:
```python
def __call__(self, args, kwargs):
# ... (trimmed)
return self[tuple(map(self.get_type, args))](*args, **kwargs)
```
I need to see the `multimethod.__call__` implementation.
Let's read `multimethod/__init__.py` from line 170.
<channel|><|tool_call>call:read_file{end_line:190,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:170}<tool_call|><|tool_response>
Turn 13at 240 s64 tokens out11,324 prompt tokens
Wait, I'm still missing `__call__`. Let me search for `def __call__` in `multimethod/__init__.py`.
TOOL CALL · run_command
{
"command": "grep -n \"def __call__\" multimethod/__init__.py"
}Result of run_command 152 characters
{
"status": "ok",
"stdout": "207: def __call__(self, *args, **kwargs):\n281: def __call__(self, *args, **kwargs):\n",
"stderr": "",
"exit_code": 0
}Generated tokens 64 tokens · stopped: STOP
Wait, I'm still missing `__call__`.
Let me search for `def __call__` in `multimethod/__init__.py`.
<channel|><|tool_call>call:run_command{command:<|"|>grep -n "def __call__" multimethod/__init__.py<|"|>}<tool_call|><|tool_response>
Turn 14at 244 s62 tokens out11,462 prompt tokens
Ah, line 207 is inside `multimethod` class. Let's read around there.
TOOL CALL · read_file
{
"end_line": 220,
"filepath": "multimethod/__init__.py",
"start_line": 200
}Result of read_file 955 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": " keys = groups[min(groups)] if groups else []\n funcs = {self[key] for key in keys}\n if len(funcs) == 1:\n return self.setdefault(types, *funcs)\n msg = f\"{self.__name__}: {len(keys)} methods found\" # type: ignore\n raise DispatchError(msg, types, keys)\n\n def __call__(self, *args, **kwargs):\n \"\"\"Resolve and dispatch to best method.\"\"\"\n return self[tuple(map(self.get_type, args))](*args, **kwargs)\n\n def evaluate(self):\n \"\"\"Evaluate any pending forward references.\n\n This can be called explicitly when using forward references,\n otherwise cache misses will evaluate.\n \"\"\"\n while self.pending:\n func = self.pending.pop()\n self[get_types(func)] = func\n",
"start_line": 200,
"end_line": 220,
"total_lines": 309,
"is_truncated": false
}Generated tokens 62 tokens · stopped: STOP
Ah, line 207 is inside `multimethod` class. Let's read around there.
<channel|><|tool_call>call:read_file{end_line:220,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:200}<tool_call|><|tool_response>
Turn 15at 246 s42 tokens out11,819 prompt tokens
And `__missing__` is where the magic happens.
TOOL CALL · run_command
{
"command": "grep -n \"def __missing__\" multimethod/__init__.py"
}Result of run_command 118 characters
{
"status": "ok",
"stdout": "194: def __missing__(self, types: tuple) -> Callable:\n",
"stderr": "",
"exit_code": 0
}Generated tokens 42 tokens · stopped: STOP
And `__missing__` is where the magic happens.<channel|><|tool_call>call:run_command{command:<|"|>grep -n "def __missing__" multimethod/__init__.py<|"|>}<tool_call|><|tool_response>
Turn 16at 248 s48 tokens out11,919 prompt tokens
Let's read `__missing__`.
TOOL CALL · read_file
{
"end_line": 205,
"filepath": "multimethod/__init__.py",
"start_line": 194
}Result of read_file 742 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": " def __missing__(self, types: tuple) -> Callable:\n \"\"\"Find and cache the next applicable method of given types.\"\"\"\n self.evaluate()\n if types in self:\n return self[types]\n groups = groupby(signature(types).__sub__, self.parents(types))\n keys = groups[min(groups)] if groups else []\n funcs = {self[key] for key in keys}\n if len(funcs) == 1:\n return self.setdefault(types, *funcs)\n msg = f\"{self.__name__}: {len(keys)} methods found\" # type: ignore\n raise DispatchError(msg, types, keys)",
"start_line": 194,
"end_line": 205,
"total_lines": 309,
"is_truncated": false
}Generated tokens 48 tokens · stopped: STOP
Let's read `__missing__`.
<channel|><|tool_call>call:read_file{end_line:205,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:194}<tool_call|><|tool_response>
Turn 17at 268 s279 tokens out12,200 prompt tokens
Now I see how it works.
If `f(int)` is called:
1. `self.get_type(int)` is called.
Wait, what is `self.get_type`?
In `__setitem__`:
```python
if any(map(subtype.subcheck, types)):
self.get_type = get_type # switch to slower generic type checker
```
If the multimethod has any "generic" type hints, it sets its own `get_type` method to the global `get_type` function.
Otherwise, it uses some default. What's the default?
`multimethod` inherits from `dict`. `dict` doesn't have a `get_type` method.
Wait, if `self.get_type` is not set, where does `map(self.get_type, args)` get `get_type` from?
Ah, wait... I missed where `self.get_type` is defined for a normal `multimethod` instance.
Let me check the `multimethod` class definition again.
TOOL CALL · read_file
{
"end_line": 180,
"filepath": "multimethod/__init__.py",
"start_line": 140
}Result of read_file 1,798 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": " self[get_types(func)] = func\n except (NameError, AttributeError):\n self.pending.add(func)\n\n def register(self, *args) -> Callable:\n \"\"\"Decorator for registering a function.\n\n Optionally call with types to return a decorator for unannotated functions.\n \"\"\"\n if len(args) == 1 and hasattr(args[0], '__annotations__'):\n return overload.register(self, *args) # type: ignore\n return lambda func: self.__setitem__(args, func) or func\n\n def __get__(self, instance, owner):\n return self if instance is None else types.MethodType(self, instance)\n\n def parents(self, types: tuple) -> set:\n \"\"\"Find immediate parents of potential key.\"\"\"\n parents = {key for key in self if isinstance(key, signature) and key < types}\n return parents - {ancestor for parent in parents for ancestor in parent.parents}\n\n def clean(self):\n \"\"\"Empty the cache.\"\"\"\n for key in list(self):\n if not isinstance(key, signature):\n super().__delitem__(key)\n\n def copy(self):\n \"\"\"Return a new multimethod with the same methods.\"\"\"\n other = dict.__new__(type(self))\n other.update(self)\n return other\n\n def __setitem__(self, types: tuple, func: Callable):\n self.clean()\n types = signature(types)\n parents = types.parents = self.parents(types)\n for key in self:\n if types < key and (not parents or parents & key.parents):\n key.parents -= parents\n key.parents.add(types)",
"start_line": 140,
"end_line": 180,
"total_lines": 309,
"is_truncated": false
}Generated tokens 279 tokens · stopped: STOP
Now I see how it works.
If `f(int)` is called:
1. `self.get_type(int)` is called.
Wait, what is `self.get_type`?
In `__setitem__`:
```python
if any(map(subtype.subcheck, types)):
self.get_type = get_type # switch to slower generic type checker
```
If the multimethod has any "generic" type hints, it sets its own `get_type` method to the global `get_type` function.
Otherwise, it uses some default. What's the default?
`multimethod` inherits from `dict`. `dict` doesn't have a `get_type` method.
Wait, if `self.get_type` is not set, where does `map(self.get_type, args)` get `get_type` from?
Ah, wait... I missed where `self.get_type` is defined for a normal `multimethod` instance.
Let me check the `multimethod` class definition again.<channel|><|tool_call>call:read_file{end_line:180,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:140}<tool_call|><|tool_response>
Turn 18at 271 s69 tokens out12,984 prompt tokens
I still don't see `self.get_type` definition. Let's search for `self.get_type =` in `multimethod/__init__.py`.
TOOL CALL · run_command
{
"command": "grep \"self.get_type =\" multimethod/__init__.py"
}Result of run_command 193 characters
{
"status": "ok",
"stdout": " self.get_type = type # default type checker\n self.get_type = get_type # switch to slower generic type checker\n",
"stderr": "",
"exit_code": 0
}Generated tokens 69 tokens · stopped: STOP
I still don't see `self.get_type` definition.
Let's search for `self.get_type =` in `multimethod/__init__.py`.
<channel|><|tool_call>call:run_command{command:<|"|>grep "self.get_type =" multimethod/__init__.py<|"|>}<tool_call|><|tool_response>
Turn 19at 277 s74 tokens out13,126 prompt tokens
Ah! Line 177 (approximately): `self.get_type = type # default type checker` Wait, let me see where that line is.
TOOL CALL · read_file
{
"end_line": 180,
"filepath": "multimethod/__init__.py",
"start_line": 170
}Result of read_file 546 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": " other.update(self)\n return other\n\n def __setitem__(self, types: tuple, func: Callable):\n self.clean()\n types = signature(types)\n parents = types.parents = self.parents(types)\n for key in self:\n if types < key and (not parents or parents & key.parents):\n key.parents -= parents\n key.parents.add(types)",
"start_line": 170,
"end_line": 180,
"total_lines": 309,
"is_truncated": false
}Generated tokens 74 tokens · stopped: STOP
Ah!
Line 177 (approximately): `self.get_type = type # default type checker`
Wait, let me see where that line is.
<channel|><|tool_call>call:read_file{end_line:180,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:170}<tool_call|><|tool_response>
Turn 20at 280 s67 tokens out13,375 prompt tokens
I'm still not seeing `self.get_type = type`. Let me read the WHOLE `multimethod` class.
TOOL CALL · read_file
{
"end_line": 220,
"filepath": "multimethod/__init__.py",
"start_line": 131
}Result of read_file 3,864 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": " namespace = inspect.currentframe().f_back.f_locals\n self = functools.update_wrapper(dict.__new__(cls), func)\n self.pending = set()\n self.get_type = type # default type checker\n homonym = namespace.get(func.__name__, self)\n return homonym if isinstance(homonym, multimethod) else self\n\n def __init__(self, func: Callable):\n try:\n self[get_types(func)] = func\n except (NameError, AttributeError):\n self.pending.add(func)\n\n def register(self, *args) -> Callable:\n \"\"\"Decorator for registering a function.\n\n Optionally call with types to return a decorator for unannotated functions.\n \"\"\"\n if len(args) == 1 and hasattr(args[0], '__annotations__'):\n return overload.register(self, *args) # type: ignore\n return lambda func: self.__setitem__(args, func) or func\n\n def __get__(self, instance, owner):\n return self if instance is None else types.MethodType(self, instance)\n\n def parents(self, types: tuple) -> set:\n \"\"\"Find immediate parents of potential key.\"\"\"\n parents = {key for key in self if isinstance(key, signature) and key < types}\n return parents - {ancestor for parent in parents for ancestor in parent.parents}\n\n def clean(self):\n \"\"\"Empty the cache.\"\"\"\n for key in list(self):\n if not isinstance(key, signature):\n super().__delitem__(key)\n\n def copy(self):\n \"\"\"Return a new multimethod with the same methods.\"\"\"\n other = dict.__new__(type(self))\n other.update(self)\n return other\n\n def __setitem__(self, types: tuple, func: Callable):\n self.clean()\n types = signature(types)\n parents = types.parents = self.parents(types)\n for key in self:\n if types < key and (not parents or parents & key.parents):\n key.parents -= parents\n key.parents.add(types)\n if any(map(subtype.subcheck, types)):\n self.get_type = get_type # switch to slower generic type checker\n super().__setitem__(types, func)\n self.__doc__ = self.docstring\n\n def __delitem__(self, types: tuple):\n self.clean()\n super().__delitem__(types)\n for key in self:\n if types in key.parents:\n key.parents = self.parents(key)\n self.__doc__ = self.docstring\n\n def __missing__(self, types: tuple) -> Callable:\n \"\"\"Find and cache the next applicable method of given types.\"\"\"\n self.evaluate()\n if types in self:\n return self[types]\n groups = groupby(signature(types).__sub__, self.parents(types))\n keys = groups[min(groups)] if groups else []\n funcs = {self[key] for key in keys}\n if len(funcs) == 1:\n return self.setdefault(types, *funcs)\n msg = f\"{self.__name__}: {len(keys)} methods found\" # type: ignore\n raise DispatchError(msg, types, keys)\n\n def __call__(self, *args, **kwargs):\n \"\"\"Resolve and dispatch to best method.\"\"\"\n return self[tuple(map(self.get_type, args))](*args, **kwargs)\n\n def evaluate(self):\n \"\"\"Evaluate any pending forward references.\n\n This can be called explicitly when using forward references,\n otherwise cache misses will evaluate.\n \"\"\"\n while self.pending:\n func = self.pending.pop()\n self[get_types(func)] = func\n",
"start_line": 131,
"end_line": 220,
"total_lines": 309,
"is_truncated": false,
"budget_warning": "Only 10 tool call(s) remaining (20/30 used). Finalize your edits and call submit_patch soon."
}Generated tokens 67 tokens · stopped: STOP
I'm still not seeing `self.get_type = type`.
Let me read the WHOLE `multimethod` class.<channel|><|tool_call>call:read_file{end_line:220,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:131}<tool_call|><|tool_response>
Turn 21at 334 s928 tokens out14,515 prompt tokens
Ok, I found it. `self.get_type = type` in `multimethod.__new__`.
So when calling `map(self.get_type, args)`, it's actually `map(type, args)`.
This means if `args = (int,)`, then `self.get_type(int)` is `type(int)` which is `type`. Correct.
And the error happens in `distance(cls, subclass: type)`:
```python
def distance(cls, subclass: type) -> int:
"""Return estimated distance between classes for tie-breaking."""
if getattr(cls, '__origin__', None) is typing.Union:
return min(distance(arg, subclass) for arg in cls.__args__)
mro = subclass.mro()
return mro.index(cls if cls in mro else object)
```
If `subclass` is `type`, then `subclass.mro()` is `type.mro()`, which fails.
To fix this, we can change `subclass.mro()` to `type.mro(subclass)`.
Let's double check if `type.mro(subclass)` always works for any class.
Yes, for any class `C`, `C.mro()` is just a call to `type.mro(C)`.
Wait, let's verify this.
In Python:
```python
>>> class A: pass
>>> A.mro()
[<class '__main__.A'>, <class 'object'>]
>>> type.mro(A)
[<class '__main__.A'>, <class 'object'>]
```
And for `type`:
```python
>>> type.mro(type)
[<class 'type'>, <class 'object'>]
```
Perfect.
So the fix is just changing `subclass.mro()` to `type.mro(subclass)`.
Wait, is `subclass` always a type?
The type hint says `subclass: type`.
And `self.get_type` returns `type` (or a `subtype` instance which inherits from `type`).
Yes, it should be a type.
Let's try to reproduce the error again with a better case.
I need to trigger `__missing__` and then `distance`.
To trigger `__missing__`, I need:
1. No exact match for the argument types.
2. At least one candidate that matches (is a parent).
```python
from multimethod import multimethod
@multimethod
def f(x: object):
print("object")
f(int)
```
In this case:
`f(int)`
- `self.get_type(int)` returns `type`.
- `self` has only one key: `signature((object,))`.
- `(type,)` is not in `self`.
- `__missing__((type,))` is called.
- `self.parents((type,))` is called.
- `signature((object,)) < (type,)` should be true because `issubclass(type, object)` is true.
- So `self.parents((type,))` returns `{signature((object,))}`.
- `groupby(signature((type,)).__sub__, {signature((object,))})` is called.
- `signature((type,)).__sub__(signature((object,)))` is called.
- In `__sub__`, `map(distance, (object,), (type,))` is called.
- `distance(object, type)` is called.
- `subclass` is `type`.
- `subclass.mro()` is `type.mro()`.
- BOOM!
Let's test this reproduction script.
TOOL CALL · run_command
{
"command": "python3 - <<'PY'\nfrom multimethod import multimethod\n\n@multimethod\ndef f(x: object):\n print(\"object\")\n\ntry:\n f(int)\n print(\"success\")\nexcept Exception as e:\n import traceback\n traceback.print_exc()\nPY\n"
}Result of run_command 190 characters
{
"status": "ok",
"stdout": "object\nsuccess\n",
"stderr": "",
"exit_code": 0,
"budget_warning": "Only 9 tool call(s) remaining (21/30 used). Finalize your edits and call submit_patch soon."
}Generated tokens 928 tokens · stopped: STOP
Ok, I found it. `self.get_type = type` in `multimethod.__new__`.
So when calling `map(self.get_type, args)`, it's actually `map(type, args)`.
This means if `args = (int,)`, then `self.get_type(int)` is `type(int)` which is `type`. Correct.
And the error happens in `distance(cls, subclass: type)`:
```python
def distance(cls, subclass: type) -> int:
"""Return estimated distance between classes for tie-breaking."""
if getattr(cls, '__origin__', None) is typing.Union:
return min(distance(arg, subclass) for arg in cls.__args__)
mro = subclass.mro()
return mro.index(cls if cls in mro else object)
```
If `subclass` is `type`, then `subclass.mro()` is `type.mro()`, which fails.
To fix this, we can change `subclass.mro()` to `type.mro(subclass)`.
Let's double check if `type.mro(subclass)` always works for any class.
Yes, for any class `C`, `C.mro()` is just a call to `type.mro(C)`.
Wait, let's verify this.
In Python:
```python
>>> class A: pass
>>> A.mro()
[<class '__main__.A'>, <class 'object'>]
>>> type.mro(A)
[<class '__main__.A'>, <class 'object'>]
```
And for `type`:
```python
>>> type.mro(type)
[<class 'type'>, <class 'object'>]
```
Perfect.
So the fix is just changing `subclass.mro()` to `type.mro(subclass)`.
Wait, is `subclass` always a type?
The type hint says `subclass: type`.
And `self.get_type` returns `type` (or a `subtype` instance which inherits from `type`).
Yes, it should be a type.
Let's try to reproduce the error again with a better case.
I need to trigger `__missing__` and then `distance`.
To trigger `__missing__`, I need:
1. No exact match for the argument types.
2. At least one candidate that matches (is a parent).
```python
from multimethod import multimethod
@multimethod
def f(x: object):
print("object")
f(int)
```
In this case:
`f(int)`
- `self.get_type(int)` returns `type`.
- `self` has only one key: `signature((object,))`.
- `(type,)` is not in `self`.
- `__missing__((type,))` is called.
- `self.parents((type,))` is called.
- `signature((object,)) < (type,)` should be true because `issubclass(type, object)` is true.
- So `self.parents((type,))` returns `{signature((object,))}`.
- `groupby(signature((type,)).__sub__, {signature((object,))})` is called.
- `signature((type,)).__sub__(signature((object,)))` is called.
- In `__sub__`, `map(distance, (object,), (type,))` is called.
- `distance(object, type)` is called.
- `subclass` is `type`.
- `subclass.mro()` is `type.mro()`.
- BOOM!
Let's test this reproduction script.
<channel|><|tool_call>call:run_command{command:<|"|>python3 - <<'PY'
from multimethod import multimethod
@multimethod
def f(x: object):
print("object")
try:
f(int)
print("success")
except Exception as e:
import traceback
traceback.print_exc()
PY
<|"|>}<tool_call|><|tool_response>
Turn 22at 406 s320 tokens out4,815 prompt tokens
Wait, it succeeded? Why? Ah, I see why. `f(int)` `args` is `(int,)`. `self.get_type` is `type`. `self.get_type(int)` is `type(int)` which is `type`. So `types` is `(type,)`. In my reproduction: `@multimethod` `def f(x: object): ...` This registers `f` with types `(object,)`. Wait, if I use `def f(x: object)`, then `get_types(f)` is `(object,)`. So the multimethod has one entry: `(object,) -> f`. When I call `f(int)`, it looks for `(type,)`. `(type,)` is not in `self`. So it enters `__missing__((type,))`. It finds `(object,)` as a parent. It calculates distance between `(object,)` and `(type,)`. `distance(object, type)` is called. Wait, why didn't it crash? Ah! I know why. Maybe `type` in some Python versions does have `mro()`? No, `type.mro` is a method. `type.mro()` should fail if not bound. Wait, let me check the Python version.
TOOL CALL · run_command
{
"command": "python3 --version"
}Result of run_command 189 characters
{
"status": "ok",
"stdout": "Python 3.10.19\n",
"stderr": "",
"exit_code": 0,
"budget_warning": "Only 8 tool call(s) remaining (22/30 used). Finalize your edits and call submit_patch soon."
}Generated tokens 320 tokens · stopped: STOP
Wait, it succeeded? Why?
Ah, I see why.
`f(int)`
`args` is `(int,)`.
`self.get_type` is `type`.
`self.get_type(int)` is `type(int)` which is `type`.
So `types` is `(type,)`.
In my reproduction:
`@multimethod`
`def f(x: object): ...`
This registers `f` with types `(object,)`.
Wait, if I use `def f(x: object)`, then `get_types(f)` is `(object,)`.
So the multimethod has one entry: `(object,) -> f`.
When I call `f(int)`, it looks for `(type,)`.
`(type,)` is not in `self`.
So it enters `__missing__((type,))`.
It finds `(object,)` as a parent.
It calculates distance between `(object,)` and `(type,)`.
`distance(object, type)` is called.
Wait, why didn't it crash?
Ah! I know why.
Maybe `type` in some Python versions does have `mro()`?
No, `type.mro` is a method. `type.mro()` should fail if not bound.
Wait, let me check the Python version.<channel|><|tool_call>call:run_command{command:<|"|>python3 --version<|"|>}<tool_call|><|tool_response>
Turn 23at 408 s44 tokens out5,220 prompt tokens
Wait, let me test `type.mro()` in a shell.
TOOL CALL · run_command
{
"command": "python3 -c \"print(type.mro())\""
}Result of run_command 508 characters
{
"status": "error",
"error_type": "CommandError",
"error_message": "Traceback (most recent call last):\n File \"<string>\", line 1, in <module>\nTypeError: unbound method type.mro() needs an argument\n",
"details": {
"stdout": "",
"stderr": "Traceback (most recent call last):\n File \"<string>\", line 1, in <module>\nTypeError: unbound method type.mro() needs an argument\n",
"exit_code": 1
},
"budget_warning": "Only 7 tool call(s) remaining (23/30 used). Finalize your edits and call submit_patch soon."
}Generated tokens 44 tokens · stopped: STOP
Wait, let me test `type.mro()` in a shell.
<channel|><|tool_call>call:run_command{command:<|"|>python3 -c "print(type.mro())"<|"|>}<tool_call|><|tool_response>
Turn 24at 421 s292 tokens out5,434 prompt tokens
Okay, so `type.mro()` DOES fail.
So why did my reproduction script succeed?
Wait, I might have missed something.
```python
@multimethod
def f(x: object):
print("object")
f(int)
```
Let's look at `multimethod.__call__`:
```python
def __call__(self, *args, **kwargs):
"""Resolve and dispatch to best method."""
return self[tuple(map(self.get_type, args))](*args, **kwargs)
```
Wait, if `self.get_type` is `type`, then `map(type, (int,))` gives `(type(int),)` which is `(type,)`.
So it's `self[(type,)]`.
If `(type,)` is not in `self`, it calls `__missing__((type,))`.
If `(object,)` is the only key, `self.parents((type,))` should return `{(object,)}`.
Wait, let me check `signature.__lt__` (which is what `key < types` uses in `parents`).
TOOL CALL · read_file
{
"end_line": 90,
"filepath": "multimethod/__init__.py",
"start_line": 60
}Result of read_file 1,508 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": " def __init__(self, tp, *args):\n if isinstance(self.__origin__, abc.ABCMeta):\n self.__origin__.register(self)\n\n def __getstate__(self) -> tuple:\n return self.__origin__, self.__args__\n\n def __eq__(self, other) -> bool:\n return isinstance(other, subtype) and self.__getstate__() == other.__getstate__()\n\n def __hash__(self) -> int:\n return hash(self.__getstate__())\n\n def __subclasscheck__(self, subclass: type) -> bool:\n origin = getattr(subclass, '__extra__', getattr(subclass, '__origin__', subclass))\n args = getattr(subclass, '__args__', ())\n if origin is typing.Union:\n return all(issubclass(cls, self) for cls in args)\n if self.__origin__ is typing.Union:\n return issubclass(subclass, self.__args__)\n nargs = len(self.__args__)\n if self.__origin__ is tuple and self.__args__[-1:] == (Ellipsis,):\n nargs -= 1\n args = args[:nargs]\n return ( # check args first to avoid a recursion error in ABCMeta\n len(args) == nargs\n and issubclass(origin, self.__origin__)\n and all(map(issubclass, args, self.__args__))\n )\n\n @classmethod",
"start_line": 60,
"end_line": 90,
"total_lines": 309,
"is_truncated": false,
"budget_warning": "Only 6 tool call(s) remaining (24/30 used). Finalize your edits and call submit_patch soon."
}Generated tokens 292 tokens · stopped: STOP
Okay, so `type.mro()` DOES fail.
So why did my reproduction script succeed?
Wait, I might have missed something.
```python
@multimethod
def f(x: object):
print("object")
f(int)
```
Let's look at `multimethod.__call__`:
```python
def __call__(self, *args, **kwargs):
"""Resolve and dispatch to best method."""
return self[tuple(map(self.get_type, args))](*args, **kwargs)
```
Wait, if `self.get_type` is `type`, then `map(type, (int,))` gives `(type(int),)` which is `(type,)`.
So it's `self[(type,)]`.
If `(type,)` is not in `self`, it calls `__missing__((type,))`.
If `(object,)` is the only key, `self.parents((type,))` should return `{(object,)}`.
Wait, let me check `signature.__lt__` (which is what `key < types` uses in `parents`).
<channel|><|tool_call>call:read_file{end_line:90,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:60}<tool_call|><|tool_response>
Turn 25at 425 s56 tokens out6,190 prompt tokens
Wait, I missed the `__lt__` method. Let me find where `__lt__` is defined in `signature`.
TOOL CALL · run_command
{
"command": "grep -n \"__lt__\" multimethod/__init__.py"
}Result of run_command 215 characters
{
"status": "ok",
"stdout": "117: def __lt__(self, other) -> bool:\n",
"stderr": "",
"exit_code": 0,
"budget_warning": "Only 5 tool call(s) remaining (25/30 used). Finalize your edits and call submit_patch soon."
}Generated tokens 56 tokens · stopped: STOP
Wait, I missed the `__lt__` method. Let me find where `__lt__` is defined in `signature`.
<channel|><|tool_call>call:run_command{command:<|"|>grep -n "__lt__" multimethod/__init__.py<|"|>}<tool_call|><|tool_response>
Turn 26at 426 s48 tokens out6,336 prompt tokens
Let me read `signature.__lt__`.
TOOL CALL · read_file
{
"end_line": 130,
"filepath": "multimethod/__init__.py,start_line=110"
}Result of read_file 552 characters
{
"status": "error",
"error_type": "FileReadError",
"error_message": "404 Client Error for http+docker://localhost/v1.52/containers/6325b670922da737a17284e09f93b7e32c9fb6bca9464137bccb34f04130d825/archive?path=%2Fworkspace%2Fmultimethod%2F__init__.py%2Cstart_line%3D110: Not Found (\"Could not find the file /workspace/multimethod/__init__.py,start_line=110 in container 6325b670922da737a17284e09f93b7e32c9fb6bca9464137bccb34f04130d825\")",
"budget_warning": "Only 4 tool call(s) remaining (26/30 used). Finalize your edits and call submit_patch soon."
}Generated tokens 48 tokens · stopped: STOP
Let me read `signature.__lt__`.
<channel|><|tool_call>call:read_file{end_line:130,filepath:<|"|>multimethod/__init__.py,start_line=110<|"|>}<tool_call|><|tool_response>
Turn 27at 429 s51 tokens out6,659 prompt tokens
My bad, I put the start line in the filepath.
TOOL CALL · read_file
{
"end_line": 130,
"filepath": "multimethod/__init__.py",
"start_line": 110
}Result of read_file 872 characters
{
"status": "ok",
"filepath": "multimethod/__init__.py",
"content": "\n def __new__(cls, types: Iterable):\n return tuple.__new__(cls, map(subtype, types))\n\n def __le__(self, other) -> bool:\n return len(self) <= len(other) and all(map(issubclass, other, self))\n\n def __lt__(self, other) -> bool:\n return self != other and self <= other\n\n def __sub__(self, other) -> tuple:\n \"\"\"Return relative distances, assuming self >= other.\"\"\"\n return tuple(map(distance, other, self))\n\n\nclass multimethod(dict):\n \"\"\"A callable directed acyclic graph of methods.\"\"\"\n\n pending: set\n\n def __new__(cls, func):",
"start_line": 110,
"end_line": 130,
"total_lines": 309,
"is_truncated": false,
"budget_warning": "Only 3 tool call(s) remaining (27/30 used). Finalize your edits and call submit_patch soon."
}Generated tokens 51 tokens · stopped: STOP
My bad, I put the start line in the filepath.
<channel|><|tool_call>call:read_file{end_line:130,filepath:<|"|>multimethod/__init__.py<|"|>,start_line:110}<tool_call|><|tool_response>
Patch, tests and logs
Final code change Included
Test output Missing
Not saved for this rollout. Nothing has been inferred or reconstructed.
Test errors Missing
Not saved for this rollout. Nothing has been inferred or reconstructed.
Test report (JUnit) Missing
Not saved for this rollout. Nothing has been inferred or reconstructed.
Agent log Included
[ 0.0s] 📋 System Prompt: You are a principal Python software engineer resolving a repository issue in `/workspace`.
[ 0.0s] 🎯 Task Prompt: You are evaluating a software engineering task for repository coady/multimethod.
[ 23.0s] 💭 (1005 chars) "The user is reporting a `TypeError` when using `type` or a metaclass as a type hint in a
multimethod.
The traceback poin..."
[ 23.0s] 🔧 run_command grep -rn --include="*.py" "mro()" .
[ 23.0s] → ./multimethod/__init__.py:102: mro = subclass.mro()
[ 28.9s] 💭 (155 chars) "Wait, the grep says line 102. The traceback says 103 (likely difference in versions or line
endings).
Let's read `multim..."
[ 28.9s] 📖 read_file (multimethod/__init__.py)
[ 28.9s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': ' nargs = len(self.__args__)\n
if self.…
[ 39.5s] 💭 (579 chars) "Wait, the traceback said line 103/104.
Let's look at `distance` function first:
```python
def distance(cls, subclass: ty..."
[ 39.5s] 📖 read_file (multimethod/__init__.py)
[ 39.6s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': ' """Return relative
distances, assuming self …
[ 101.1s] 💭 (3120 chars) "In `signature.__sub__`:
```python
def __sub__(self, other) -> tuple:
"""Return relative distances, assuming ..."
[ 101.1s] 🔧 run_command (13 lines) python3 - <<'PY'
[ 101.2s] → success
[ 166.5s] 💭 (2959 chars) "Wait, it worked?
The example in the issue says:
```python
@multimethod
def f(x: type):
print("success")
f(int)
```
..."
[ 166.5s] 🔧 run_command (13 lines) python3 - <<'PY'
[ 166.5s] → object
[ 170.3s] 💭 (103 chars) "Wait, it still worked? Why?
Maybe `self.get_type(int)` is NOT `type`?
Let's check what `get_type` does."
[ 170.3s] 📖 read_file (multimethod/__init__.py)
[ 170.4s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': ' return object\n
tp = typi…
[ 174.6s] 💭 (66 chars) "I need to see `get_type`. It's probably a method of `multimethod`."
[ 174.6s] 📖 read_file (multimethod/__init__.py)
[ 174.7s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': ' return
overload.register(self, *args) #…
[ 177.5s] 💭 (63 chars) "I still don't see `get_type`. Let me search for `def get_type`."
[ 177.5s] 🔧 run_command grep -n "def get_type" multimethod/__init__.py
[ 177.5s] → 21:def get_types(func: Callable) -> tuple:
[ 190.3s] 💭 (537 chars) "Wait, there are several `get_type` definitions. Python allows overwriting them if they are
in the same scope? No, they a..."
[ 190.3s] 📖 read_file (multimethod/__init__.py)
[ 190.4s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': 'get_type.__doc__ = """Return a
generic `subtype` whi…
[ 215.0s] 💭 (768 chars) "Ah, `get_type` is itself a `multimethod`!
```python
@multimethod # type: ignore[no-redef]
def get_type(arg: tuple):
..."
[ 215.0s] 🔧 run_command (4 lines) python3 - <<'PY'
[ 215.1s] → get_type(int) = <class 'type'>
[ 224.2s] 💭 (270 chars) "Wait, `get_type(int)` returns `<class 'type'>`?
How? `int` is not a tuple, Mapping or Iterable.
Let's look at the defini..."
[ 224.2s] 📖 read_file (multimethod/__init__.py)
[ 224.2s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': 'import abc\nimport
collections\nimport functools\nim…
[ 232.7s] 💭 (310 chars) "Wait, I see it now!
I missed this part in the previous `read_file`:
```python
def __call__(self, args, kwargs):
# ....."
[ 232.7s] 📖 read_file (multimethod/__init__.py)
[ 232.7s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': ' other.update(self)\n
return other\n\n…
[ 239.3s] 💭 (98 chars) "Wait, I'm still missing `__call__`.
Let me search for `def __call__` in `multimethod/__init__.py`."
[ 239.3s] 🔧 run_command grep -n "def __call__" multimethod/__init__.py
[ 239.3s] → 207: def __call__(self, *args, **kwargs):
[ 243.4s] 💭 (68 chars) "Ah, line 207 is inside `multimethod` class. Let's read around there."
[ 243.4s] 📖 read_file (multimethod/__init__.py)
[ 243.4s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': ' keys = groups[min(groups)]
if groups else []…
[ 245.4s] 💭 (45 chars) "And `__missing__` is where the magic happens."
[ 245.4s] 🔧 run_command grep -n "def __missing__" multimethod/__init__.py
[ 245.4s] → 194: def __missing__(self, types: tuple) -> Callable:
[ 247.4s] 💭 (25 chars) "Let's read `__missing__`."
[ 247.4s] 📖 read_file (multimethod/__init__.py)
[ 247.4s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': ' def __missing__(self, types:
tuple) -> Callable:…
[ 267.8s] 💭 (759 chars) "Now I see how it works.
If `f(int)` is called:
1. `self.get_type(int)` is called.
Wait, what is `self.get_type`?
In `__s..."
[ 267.8s] 📖 read_file (multimethod/__init__.py)
[ 267.8s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': ' self[get_types(func)] =
func\n ex…
[ 270.5s] 💭 (110 chars) "I still don't see `self.get_type` definition.
Let's search for `self.get_type =` in `multimethod/__init__.py`."
[ 270.5s] 🔧 run_command grep "self.get_type =" multimethod/__init__.py
[ 270.6s] → self.get_type = type # default type checker
[ 276.2s] 💭 (112 chars) "Ah!
Line 177 (approximately): `self.get_type = type # default type checker`
Wait, let me see where that line is."
[ 276.2s] 📖 read_file (multimethod/__init__.py)
[ 276.2s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': ' other.update(self)\n
return other\n\n…
[ 279.6s] 💭 (87 chars) "I'm still not seeing `self.get_type = type`.
Let me read the WHOLE `multimethod` class."
[ 279.6s] 📖 read_file (multimethod/__init__.py)
[ 279.7s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': ' namespace =
inspect.currentframe().f_back.f_…
[ 333.2s] 💭 (2513 chars) "Ok, I found it. `self.get_type = type` in `multimethod.__new__`.
So when calling `map(self.get_type, args)`, it's actual..."
[ 333.2s] 🔧 run_command (14 lines) python3 - <<'PY'
[ 333.3s] → object
[ 405.5s] 💭 (844 chars) "Wait, it succeeded? Why?
Ah, I see why.
`f(int)`
`args` is `(int,)`.
`self.get_type` is `type`.
`self.get_type(int)` is ..."
[ 405.5s] 🔧 run_command python3 --version
[ 405.5s] → Python 3.10.19
[ 407.2s] 💭 (42 chars) "Wait, let me test `type.mro()` in a shell."
[ 407.2s] 🔧 run_command python3 -c "print(type.mro())"
[ 407.3s] → error (exit 0):
[ 420.6s] 💭 (766 chars) "Okay, so `type.mro()` DOES fail.
So why did my reproduction script succeed?
Wait, I might have missed something.
```pyt..."
[ 420.6s] 📖 read_file (multimethod/__init__.py)
[ 420.6s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': " def __init__(self, tp, *args):\n
if isins…
[ 424.1s] 💭 (89 chars) "Wait, I missed the `__lt__` method. Let me find where `__lt__` is defined in `signature`."
[ 424.1s] 🔧 run_command grep -n "__lt__" multimethod/__init__.py
[ 424.2s] → 117: def __lt__(self, other) -> bool:
[ 425.7s] 💭 (31 chars) "Let me read `signature.__lt__`."
[ 425.7s] 📖 read_file (multimethod/__init__.py,start_line=110)
[ 425.7s] ❌ {'status': 'error', 'error_type': 'FileReadError', 'error_message': '404 Client Error for
http+docker://localhost/v1.52/…
[ 428.2s] 💭 (45 chars) "My bad, I put the start line in the filepath."
[ 428.2s] 📖 read_file (multimethod/__init__.py)
[ 428.3s] ✓ {'status': 'ok', 'filepath': 'multimethod/__init__.py', 'content': '\n def __new__(cls, types:
Iterable):\n re…
Native result row
{
"agent_error": "Agent exceeded session timeout (7.5 min)",
"duration_seconds": 452.76,
"error": "Empty agent patch",
"grade": {
"error": "Empty agent patch",
"resolved": false,
"strict_clean_patch": false,
"test_exit_code": -1
},
"instance_id": "coady__multimethod-26",
"pass_idx": 0,
"patch_chars": 0,
"phase1_seconds": 452.76,
"repo": "coady/multimethod",
"request_log_path": "/kaggle-root/working/r31/rollouts_X/requests/coady__multimethod-26__p0__r0.jsonl",
"resolved": false,
"rollout_idx": 0,
"run_key": "coady__multimethod-26__p0__r0",
"strict_clean_patch": false,
"tool_calls": 27,
"total_llm_calls": 27,
"trace_path": "/kaggle-root/working/r31/rollouts_X/traces/trace_coady__multimethod-26__p0__r0.json"
}