cannot mmap an empty file

[FoolerNanke]

When using this project, I encountered this problem:

JQ9XW1MWR2:SeaGOAT nanke$ poetry run seagoat-server start --port 12345 /Users/nanke/python/great/SeaGOAT/seagoat/queue
2025-06-10 15:11:08,276 Creating server...
2025-06-10 15:11:08,277 Starting worker thread...
2025-06-10 15:11:08,279 Serving on http://0.0.0.0:12345
2025-06-10 15:11:08,883 Checking repository for new changes
2025-06-10 15:11:08,937 Estimated ripgrep cache size: 0.00 megabytes (0 bytes). Line count 0
/Users/nanke/Library/Caches/seagoat/8550f36a02741952def6b71ac6234027b058bbf738675f6c0bcf833abe7a5fb3/mmapadd
Exception in thread Thread-1 (_worker_function):
Traceback (most recent call last):
File "/Users/nanke/python/great/SeaGOAT/seagoat/queue/base_queue.py", line 78, in _worker_function
task = self._task_queue.get(timeout=0.1)
File "/opt/homebrew/Cellar/python@3.13/3.13.3/Frameworks/Python.framework/Versions/3.13/lib/python3.13/queue.py", line 212, in get
raise Empty
_queue.Empty

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/opt/homebrew/Cellar/python@3.13/3.13.3/Frameworks/Python.framework/Versions/3.13/lib/python3.13/threading.py", line 1041, in _bootstrap_inner
self.run()
~~~~~~~~^^
File "/opt/homebrew/Cellar/python@3.13/3.13.3/Frameworks/Python.framework/Versions/3.13/lib/python3.13/threading.py", line 992, in run
self._target(*self._args, **self._kwargs)
~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/nanke/python/great/SeaGOAT/seagoat/queue/base_queue.py", line 83, in _worker_function
self.handle_maintenance(context)
~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^
File "/Users/nanke/python/great/SeaGOAT/seagoat/queue/task_queue.py", line 68, in handle_maintenance
remaining_chunks_to_analyze = context["seagoat_engine"].analyze_codebase(
self.kwargs["minimum_chunks_to_analyze"]
)
File "/Users/nanke/python/great/SeaGOAT/seagoat/engine.py", line 78, in analyze_codebase
fetcher"cache_repo"
~~~~~~~~~~~~~~~~~~~~~^^
File "/Users/nanke/python/great/SeaGOAT/seagoat/sources/ripgrep.py", line 112, in cache_repo
memory_cache.rebuild()
~~~~~~~~~~~~~~~~~~~~^^
File "/Users/nanke/python/great/SeaGOAT/seagoat/sources/ripgrep.py", line 91, in rebuild
self._data = mmap.mmap(cache_file.fileno(), 0)
~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^
ValueError: cannot mmap an empty file
^CServer started at http://localhost:12345

[kantord]

this is on windows?

[bikemazzell]

Looks like it could be address by an extra check in repgrip.py ~ line 89:

  with open(self.file_path, "r+b") as cache_file:
                # Check if file is empty
                if cache_file.seek(0, 2) == 0: 
                    self._data = ""
                else:
                    cache_file.seek(0)
                    self._data = mmap.mmap(cache_file.fileno(), 0)