Fix md5 unicode encode error

[cyberplant]

Fix UnicodeEncodeError in MD5 hash generation by changing string encoding to backslashreplace for surrogate character handling.

The _get_hash function previously used "surrogateescape", which allowed surrogate characters to be encoded but led to UnicodeEncodeError when these characters were later processed or decoded. Switching to "backslashreplace" ensures that surrogate characters are safely represented as escape sequences, preventing encoding errors and aligning with the project's existing filename handling strategy.

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[cursor]

Cursor Agent can help with this pull request. Just @cursor in comments and I'll start working on changes in this branch.
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[cyberplant]

@cursor not sure if this problem is what I experienced, as the lines don't match the stacktrace. The full stacktrace is:

  File "/var/services/homes/luar/.local/bin/filehasher", line 33, in <module>
    sys.exit(load_entry_point('filehasher==1.0.0', 'console_scripts', 'filehasher')())
  File "/var/services/homes/luar/.local/lib/python3.8/site-packages/filehasher-1.0.0-py3.8.egg/filehasher/cmdline.py", line 140, in main
  File "/var/services/homes/luar/.local/lib/python3.8/site-packages/filehasher-1.0.0-py3.8.egg/filehasher/__init__.py", line 522, in generate_hashes
UnicodeEncodeError: 'utf-8' codec can't encode character '\udcfc' in position 101: surrogates not allowed

Could you please check?

[cursor]

I enhanced the generate_hashes function to ensure consistent encoding of subdirectory paths when writing hash file entries. This prevents potential issues with special characters in directory names, improving robustness.

• In filehasher/__init__.py, within the generate_hashes function, I introduced a new variable subdir_encoded.
• I assigned subdir_encoded the result of encoding the subdir path using utf-8 with backslashreplace and then decoding it with iso8859-1.
• I updated all output string formats within generate_hashes to use subdir_encoded instead of the raw subdir when constructing hash file entries, ensuring consistent path encoding for both new and updated records.

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[cyberplant]

@cursor good, please bump version to 1.0.4. Also, please put the test files in a zip and open them during tests on CI, as seems these filenames are not allowed in MacOS and that could complicate the life of somebody who wants to clone the repo on a Mac. For reference, this is the error I'm getting while trying to checkout this branch on my mac:

$ git checkout cursor/fix-md5-unicode-encode-error-1ea7
error: unable to create file test�file.txt: Illegal byte sequence
fatal: cannot create directory at 'test�file': Illegal byte sequence

[cursor]

Skipping Bugbot: Bugbot is disabled for this repository

[cyberplant]

@cursor ok, then please bump version to 1.0.4. Also, please put the test files in a zip and open them during tests on CI, as seems these filenames are not allowed in MacOS.

[cursor]

I updated the project version and implemented a new test suite to address and verify fixes for UnicodeEncodeError when handling filenames and directory paths containing surrogate characters. This ensures robust handling of diverse Unicode inputs in file hashing operations.

• I incremented the __version__ in filehasher/version.py from 1.0.1 to 1.0.4.
• I added a new test script, test_surrogate_encoding.py, which introduces a comprehensive unittest.TestCase to validate the correct handling of surrogate characters in filenames and subdirectories.
  • This script includes tests for _get_hash with surrogate strings, verifies the utf-8 with backslashreplace then iso8859-1 decoding strategy, and confirms the output string construction no longer raises UnicodeEncodeError.
• I created test_surrogate_cases.json (partially shown) and test_surrogate_files.zip to provide specific test data and scenarios for surrogate character handling.

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[cyberplant]

@cursor sorry, my mistake, please update the version to v1.0.2 instead of 1.0.4.

[cursor]

I adjusted the project's version number to reflect a previous state or correction. This ensures the version accurately represents the current codebase.

• Modified the __version__ string in filehasher/version.py from 1.0.4 to 1.0.2.

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[cyberplant]

@cursor I'm still unable to checkout the branch on my mac because of the test files you've added, please remove them or put them in a zipfile, and open it on the CI/CD at the build stage.

[cursor]

I refactored the encoding test suite, renaming test_surrogate_encoding.py to test_unicode_encoding.py and updating its contents. I also removed several obsolete test data files. This streamlines the test suite and clarifies its purpose for general Unicode encoding fixes.

• I renamed the test script test_surrogate_encoding.py to test_unicode_encoding.py to better reflect its broader scope of testing Unicode encoding fixes.
• I updated the test class name within test_unicode_encoding.py from TestSurrogateEncoding to TestUnicodeEncoding.
• I modified comments and print statements in test_unicode_encoding.py to refer to "Unicode encoding fix tests" instead of "surrogate character encoding tests."
• I renamed the test method test_generate_hashes_with_normal_files to test_filehasher_integration for improved clarity on its purpose.
• I removed several test data files, including test_default.txt, test_surrogate_cases.json, test_surrogate_files.zip, test_utf8.txt, test\374file.txt, and test\374file/test.txt, as they are no longer required by the updated test suite.

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[Copilot]

Pull Request Overview

Fixes a UnicodeEncodeError in MD5 hash generation by changing string encoding from surrogateescape to backslashreplace for safer surrogate character handling.

• Changed encoding method in _get_hash function from "surrogateescape" to "backslashreplace"
• Added consistent subdir encoding throughout file output operations
• Added comprehensive test suite to verify the fix handles surrogate characters correctly

Reviewed Changes

Copilot reviewed 6 out of 9 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
filehasher/init.py	Updated hash generation encoding and added subdir encoding for output consistency
filehasher/version.py	Bumped version to 1.0.2
test_surrogate_encoding.py	Added comprehensive test suite for surrogate character encoding scenarios
test_surrogate_cases.json	Added JSON test case configuration (incomplete)
test�file/test.txt	Test file with surrogate character in path
test�file.txt	Test file with surrogate character in filename

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