development.md

Development

Project structure

.
├── delete-media-duplicates.sh    # Main script
├── test-delete-media-duplicates.sh  # Test suite
├── docs/
│   ├── usage.md                  # End-user documentation
│   ├── development.md            # This file
│   └── testing.md                # Testing guide
├── readme.md
├── license.txt
└── .editorconfig

Design decisions

Tab-delimited internal storage

The script uses a tab character ($'\t') as a delimiter between MD5 hashes and file paths in the internal array. This avoids issues with colons in filenames (which broke the original colon-delimited approach).

Null-byte file iteration

Files are discovered with find -print0 and read with read -d '' to correctly handle filenames containing spaces, newlines, or other special characters.

ffmpeg stdin redirect

The ffmpeg command uses < /dev/null to prevent it from consuming stdin, which would otherwise interfere with the while read loop.

Graceful ffmpeg failures

If ffmpeg cannot process a file (non-media, corrupt, etc.), the script catches the failure, prints a warning, and continues processing remaining files.

Coding conventions

• Shell: Bash with set -euo pipefail
• Formatting: Follow .editorconfig settings (spaces, final newline)
• Quoting: All variables are double-quoted to prevent word splitting
• Comments: Inline comments for non-obvious logic only

Making changes

1. Edit delete-media-duplicates.sh
2. Run the test suite to verify nothing is broken (see testing.md)
3. Test manually with a real media directory if the change affects file handling
4. Commit with a descriptive message