A zero-dependency HTML pretty printer implemented entirely in pure Bash.
This tool formats and indents HTML files using standard shell utilities (bash, sed, printf) without requiring heavy runtimes like Node.js or Python. It demonstrates complex string manipulation and state management within a shell environment.
Unlike simple find-and-replace scripts, this formatter uses a state-based approach to handle HTML structure correctly:
- Zero Dependencies: Runs on virtually any Unix-like system with Bash 4.0+.
- Context-Aware Indentation: Distinguishes between block elements (which require new lines and indentation) and inline elements (which must preserve text flow).
- Stack-Based Logic: Implements an internal array as a stack to track nested inline tags, ensuring correct formatting for complex structures like
<a><span>text</span></a>. - Regex Parsing: Utilizes
BASH_REMATCHfor tokenizing HTML tags and content streams.
Run the formatter:
./html.sh <input_file.html> <output_file.html>Below is a comparison showing raw, unformatted input versus the output generated by this script.
This tool is designed for standard, compliant HTML structures. As it relies on regular expressions rather than a full DOM parser, it may encounter issues with extremely malformed HTML or attributes containing escaped angle brackets inside quotes.
MIT License