Upgrade broccoli-persistent-filter to v3

.travis.yml

@@ -1,4 +1,3 @@
 language: node_js
 node_js:
- - '8'
- - '6'
+ - '10'

index.js

@@ -19,35 +19,35 @@ module.exports = class extends Filter {
  return 'css';
  }
 
- processString(text, relativePath) {
- const options = Object.assign({
+ async processString(text, relativePath) {
+ const options = {
  from: relativePath,
- to: relativePath
- }, this.options);
+ to: relativePath,
+ ...this.options
+ };
 
  // Support explicit override of inline sourcemaps
  if (options.sourcemap !== null || options.sourcemap !== undefined) {
  options.map = options.sourcemap ? 'inline' : false;
  }
 
- return postcss(autoprefixer(options))
- .process(text, options)
- .then(result => {
- const warnings = result.warnings();
-
- if (warnings.length > 0) {
- console.error(warnings.join('\n'));
- }
-
- return result.css;
- })
- .catch(error => {
- if (error.name === 'CssSyntaxError') {
- // TODO: Find a way to hide the stack so to adhere to the PostCSS guidelines
- error.message += error.showSourceCode();
- }
-
- throw error;
- });
+ let result;
+ try {
+ result = await postcss(autoprefixer(options)).process(text, options);
+ } catch (error) {
+ if (error.name === 'CssSyntaxError') {
+ // TODO: Find a way to hide the stack so to adhere to the PostCSS guidelines
+ error.message += error.showSourceCode();
+ }
+ throw error;
+ }
+
+ const warnings = result.warnings();
+
+ if (warnings.length > 0) {
+ console.error(warnings.join("\n"));
+ }
+
+ return result.css;
  }
 };

package.json

@@ -7,10 +7,10 @@
  "author": {
  "name": "Sindre Sorhus",
  "email": "sindresorhus@gmail.com",
- "url": "sindresorhus.com"
+ "url": "https://sindresorhus.com"
  },
  "engines": {
- "node": ">=6"
+ "node": ">=10"
  },
  "scripts": {
  "test": "xo && broccoli build temp && ava"
@@ -31,7 +31,7 @@
  ],
  "dependencies": {
  "autoprefixer": "^9.8.4",
- "broccoli-persistent-filter": "^1.1.6",
+ "broccoli-persistent-filter": "^3.0.0",
  "postcss": "^7.0.2"
  },
  "devDependencies": {