grind-assets/src/PostProcessors/SvgOptimizePostProcessor.js

Asset management for Grind

import './PostProcessor'

import '../Errors/makeSyntaxError'
import '../Support/optional'

const SVGO = optional('svgo', '>=1.1.0')

export class SvgOptimizePostProcessor extends PostProcessor {
	supportedExtensions = ['svg']
	options = {}

	constructor(app, shouldOptimize, sourceMaps) {
		super(app, shouldOptimize, sourceMaps)

		this.options = app.config.get('assets.post_processors.svg.optimize', {})

		if (typeof this.options.enabled === 'boolean') {
			this.shouldOptimize = this.options.enabled
		}
	}

	process(sourcePath, targetPath, contents) {
		if (!this.shouldOptimize || sourcePath.indexOf('.min.') >= 0) {
			return Promise.resolve(contents)
		}

		if (!SVGO.resolve()) {
			return Promise.resolve(contents)
		}

		return new SVGO.pkg(this.options)
			.optimize(contents)
			.then(result => {
				if (result.isNil) {
					const error = new Error('Unknown error optimizing SVG')
					error.file = sourcePath
					throw error
				}

				if (!result.error.isNil) {
					throw new Error(result.error)
				}

				return result.data
			})
			.catch(error => {
				if (typeof error === 'string') {
					error = new Error(error)
				}

				if (typeof error.file !== 'string') {
					error.file = sourcePath
				}

				error.message = error.message
					.replace(/^Line:\s*([0-9]+)\s*$/m, (_, line) => {
						error.line = Number(line)

						if (contents.toString().trim().startsWith('<?')) {
							error.line++
						}

						return ''
					})
					.replace(/^Column:\s*([0-9]+)\s*$/m, (_, column) => {
						error.column = Number(column)
						return ''
					})
					.replace(/^Char:\s*.+?$/m, '')
					.trim()

				return makeSyntaxError(this.app, {
					causedBy: error,
				})
					.catch(() => {
						throw error
					})
					.then(error => {
						throw error
					})
			})
	}
}