[ARROW-7973] [Developer][C++] ResourceWarnings in run_cpplint.py

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.17.0
• Component/s: C++, Developer Tools
• External issue URL: https://github.com/apache/arrow/issues/24192
• Assignee: Wes McKinney
• Reporter: Wes McKinney
• Created: 02/Mar/20 03:26
• Updated: 11/Jan/23 07:57
• Resolved: 10/Mar/20 22:21

Description

Seeing warnings like this locally

$ ninja lint
[1/1] cd /home/wesm/code/arrow/cpp/preflight...ce_dir /home/wesm/code/arrow/cpp/src --quiet
FAILED: CMakeFiles/lint 
cd /home/wesm/code/arrow/cpp/preflight-build && /home/wesm/miniconda/envs/arrow-3.7/bin/python /home/wesm/code/arrow/cpp/build-support/run_cpplint.py --cpplint_binary /home/wesm/code/arrow/cpp/build-support/cpplint.py --exclude_globs /home/wesm/code/arrow/cpp/build-support/lint_exclusions.txt --source_dir /home/wesm/code/arrow/cpp/src --quiet
/home/wesm/code/arrow/cpp/build-support/run_cpplint.py:77: ResourceWarning: unclosed file <_io.TextIOWrapper name='/home/wesm/code/arrow/cpp/build-support/lint_exclusions.txt' mode='r' encoding='UTF-8'>
  for line in open(arguments.exclude_globs):
ResourceWarning: Enable tracemalloc to get the object allocation traceback
/home/wesm/code/arrow/cpp/build-support/cpplint.py:6240: ResourceWarning: unclosed file <_io.BufferedReader name='/home/wesm/code/arrow/cpp/src/arrow/compute/kernels/add.h'>
  lines = codecs.open(filename, 'r', 'utf8', 'replace').read().split('\n')
ResourceWarning: Enable tracemalloc to get the object allocation traceback
/home/wesm/code/arrow/cpp/build-support/cpplint.py:6240: ResourceWarning: unclosed file <_io.BufferedReader name='/home/wesm/code/arrow/cpp/src/arrow/compute/kernels/util_internal.h'>
  lines = codecs.open(filename, 'r', 'utf8', 'replace').read().split('\n')
ResourceWarning: Enable tracemalloc to get the object allocation traceback

I was using PYTHONDEVMODE=1 so this may be related