suaveplan/packages/devtools/docs/compress-svg/src/plugins/cleanup-attrs/cleanup-attrs.md

cleanup-attrs — Remove Redundant SVG Attributes

(no submodules)

Purpose

cleanupAttrs strips attributes whose values match the SVG specification defaults and trims whitespace from all remaining attribute values. Many SVG authoring tools emit default attribute values explicitly (e.g. fill="black", opacity="1") that carry no information. Removing them reduces file size without changing the rendered output.

Features

• Removes attributes whose trimmed value matches the SVG default (sourced from DEFAULT_ATTRS in constants)
• Removes attributes with empty string values after trimming
• Trims leading/trailing whitespace from all attribute values
• Passes non-element nodes through unchanged
• Included in PRESET_DEFAULT, PRESET_SAFE, and PRESET_AGGRESSIVE

Usage: Basic Example

import { compressSvg } from '@suaveplan/compress-svg';
import { cleanupAttrs } from '@suaveplan/compress-svg/plugins/cleanup-attrs';

const svg = '<svg><rect fill="black" opacity="1" x="10" fill-opacity="1"/></svg>';
const result = compressSvg(svg, { plugins: [cleanupAttrs] });
// result.data === '<svg><rect x="10"/></svg>'

Usage: Advanced Example

import { cleanupAttrs } from '@suaveplan/compress-svg/plugins/cleanup-attrs';

const node = {
  type: 'element' as const,
  name: 'rect',
  attributes: { fill: 'red', opacity: '1', style: '', x: '  10  ' },
  children: [],
};
const result = cleanupAttrs.apply(node, { floatPrecision: 3, transformPrecision: 5 });
// result.attributes === { fill: 'red', x: '10' }
// opacity removed (default), style removed (empty), x trimmed

API Reference

cleanupAttrs: SvgPlugin

Property	Value
name	"cleanupAttrs"
apply	(node, options) => SvgNode | null

Iterates over each attribute:

1. Trims the value.
2. Drops the attribute if the trimmed value is empty.
3. Drops the attribute if DEFAULT_ATTRS[key] === trimmedValue.
4. Otherwise keeps the attribute with the trimmed value.

Returns the node unchanged for non-element nodes.

Default attributes removed (partial list): fill="black", fill-opacity="1", stroke-opacity="1", opacity="1", display="inline", visibility="visible", overflow="visible".

Implementation Notes

The DEFAULT_ATTRS constant is defined centrally in src/constants/index.ts so all plugins share the same definition. The plugin always returns a new node object with a fresh attributes record, even if no attributes were removed — callers should not rely on reference equality after the plugin runs. Only exact-string matches against the default values are checked; no numeric normalisation is performed (e.g. opacity="1.0" is not recognised as a default).