Prettier Tool Analysis

Overview

Prettier is a code formatter that supports CSS, HTML, JSON, YAML, Markdown, GraphQL, and many other languages. In Lintro, Prettier handles file types that oxfmt doesn’t support, while oxfmt handles JavaScript/TypeScript/Vue formatting for better performance.

File Type Responsibilities

File Types	Formatter	Why
JS, TS, JSX, TSX, Vue	oxfmt	30x faster than Prettier
CSS, SCSS, Less	Prettier	Not supported by oxfmt
HTML	Prettier	Not supported by oxfmt
JSON	Prettier	Not supported by oxfmt
YAML	Prettier	Not supported by oxfmt
Markdown	Prettier	Not supported by oxfmt
GraphQL	Prettier	Not supported by oxfmt

Core Tool Capabilities

Prettier provides extensive CLI options including:

Formatting options: --tab-width, --use-tabs, --semi, --single-quote, --quote-props, --trailing-comma
File handling: --write, --check, --config, --ignore-path, --stdin-filepath
Parser options: --parser (auto-detect or specify: css, html, json, yaml, etc.)
Output control: --list-different, --require-pragma, --insert-pragma
Debug options: --debug-check, --debug-print-doc

Lintro Implementation Analysis

✅ Preserved Features

Core Functionality:

✅ Formatting capability: Full preservation through --write flag
✅ Check mode: Preserved through --check flag
✅ File targeting: Supports file patterns and paths
✅ YAML formatting: Formats *.yml / *.yaml files (yamllint handles linting)
✅ Configuration files: Respects .prettierrc and prettier.config.js
✅ Error detection: Captures formatting violations as issues
✅ Auto-fixing: Can automatically format files when fix() is called

Supported File Patterns:

PRETTIER_FILE_PATTERNS = [
    "*.css", "*.scss", "*.less",  # Stylesheets
    "*.html",                       # HTML
    "*.json",                       # JSON
    "*.yaml", "*.yml",              # YAML
    "*.md",                         # Markdown
    "*.graphql",                    # GraphQL
]

⚠️ Limited/Missing Features

Intentionally Excluded:

❌ JavaScript/TypeScript: Use oxfmt instead (30x faster)
❌ Vue files: Use oxfmt instead

Not Implemented:

⚠️ Stdin processing: No --stdin-filepath support
⚠️ List different: Cannot use --list-different mode
⚠️ Custom ignore paths: No runtime --ignore-path specification
⚠️ Runtime formatting options: Prefer config files

🚀 Enhancements

Unified Interface:

✅ Consistent API: Same interface as other linting tools
✅ Structured output: Issues formatted as standardized Issue objects
✅ File filtering: Built-in file extension filtering
✅ Integration ready: Seamless integration with other tools

Usage Comparison

Core Prettier

# Check formatting (CSS, HTML, JSON, YAML, MD)
prettier --check "src/**/*.{css,html,json,yml,md}"

# Format files
prettier --write "src/**/*.{css,html,json,yml,md}"

Lintro (Combined oxfmt + Prettier)

# Format all supported files
lintro format --tools oxfmt,prettier

# Check formatting
lintro check --tools oxfmt,prettier

Recommendations

When to Use Core Prettier

Need specific formatting options at runtime
Require debug output or syntax validation
Working with non-standard file patterns
Need to format JS/TS (though oxfmt is faster)

When to Use Lintro Wrapper

Part of multi-tool linting pipeline
Need consistent issue reporting across tools
Want simplified configuration management
Prefer oxfmt handling JS/TS for performance

Configuration Strategy

The Lintro wrapper relies entirely on Prettier’s configuration files:

.prettierrc
.prettierrc.json
prettier.config.js
package.json “prettier” field

For runtime customization, users should modify these config files rather than passing CLI options.

Migration Notes

If you were previously using Prettier for JavaScript/TypeScript formatting through Lintro, those files are now handled by oxfmt. To maintain Prettier for JS/TS:

Use prettier directly (not through Lintro)
Or configure Lintro to skip oxfmt: lintro format --tools prettier