feat: added support for link imagesrcset attribute (#347)

Author: cap-Bernardito

README.md

@@ -86,6 +86,7 @@ Supported tags and attributes:
 - the `xlink:href` attribute of the `use` tag
 - the `href` attribute of the `use` tag
 - the `href` attribute of the `link` tag when the `rel` attribute contains `stylesheet`, `icon`, `shortcut icon`, `mask-icon`, `apple-touch-icon`, `apple-touch-icon-precomposed`, `apple-touch-startup-image`, `manifest`, `prefetch`, `preload`
+- the `imagesrcset` attribute of the `link` tag when the `rel` attribute contains `stylesheet`, `icon`, `shortcut icon`, `mask-icon`, `apple-touch-icon`, `apple-touch-icon-precomposed`, `apple-touch-startup-image`, `manifest`, `prefetch`, `preload`
 - the `content` attribute of the `meta` tag when the `name` attribute is `msapplication-tileimage`, `msapplication-square70x70logo`, `msapplication-square150x150logo`, `msapplication-wide310x150logo`, `msapplication-square310x310logo`, `msapplication-config` or when the `property` attribute is `og:image`, `og:image:url`, `og:image:secure_url`, `og:audio`, `og:audio:secure_url`, `og:video`, `og:video:secure_url`, `vk:image`
 
 #### `Boolean`

src/utils.js

@@ -652,6 +652,12 @@ const defaultAttributes = [
     type: 'src',
     filter: linkHrefFilter,
   },
+  {
+    tag: 'link',
+    attribute: 'imagesrcset',
+    type: 'srcset',
+    filter: linkHrefFilter,
+  },
   {
     tag: 'meta',
     attribute: 'content',

test/__snapshots__/esModule-option.test.js.snap

@@ -381,6 +381,7 @@ <h2>An Ordered HTML List</h2>
 <link rel="apple-touch-icon-precomposed" href="./image.png"/>
 <link rel="manifest" href="./site.webmanifest">
 <link rel="mask-icon" href="./webpack.svg" color="#5bbad5">
+<link rel="preload" as="image" imagesrcset="image.png 400w, image.png 800w, image.png 1600w" imagesizes="100vw">
 <meta name="msapplication-square70x70logo" content="./image.png">
 <meta NAME="msapplication-square70x70logo" content="./image.png">
 <meta name="msapplication-square150x150logo" content="./image.png">

test/__snapshots__/loader.test.js.snap

@@ -272,3 +272,7 @@
 <img srcset="image.png 200w,   " sizes="(max-width: 600px) 480px, 800px" src="image.png" alt="Elva dressed as a fairy">
 <img srcset=",image.png 200w" sizes="(max-width: 600px) 480px, 800px" src="image.png" alt="Elva dressed as a fairy">
 <img srcset=",image.png 200w   " sizes="(max-width: 600px) 480px, 800px" src="image.png" alt="Elva dressed as a fairy">
+
+<link rel="preload" as="image" imagesrcset="image.png 400w, image.png 800w, image.png 1600w" imagesizes="100vw">
+<link rel="preload" as="image" imagesrcset="image.png 400w" imagesizes="100vw">
+<link rel="preload" as="image" imagesrcset="" imagesizes="100vw">