style-vendorizer

Tiny CSS vendor prefixer and property alias mapper for runtime styling solutions.

Usage

Install the library with a package manager, e.g. npm:

npm install style-vendorizer

After that, import transformer functions on demand. A recommended starting point is shown below:

import {
  cssPropertyAlias,
  cssPropertyPrefixFlags,
  cssValuePrefixFlags,
} from "style-vendorizer";

function styleDeclaration(property, value) {
  let cssText = "";

  /* Resolve aliases, e.g. `gap` -> `grid-gap` */
  const propertyAlias = cssPropertyAlias(property);
  if (propertyAlias) cssText += `${propertyAlias}:${value};`;

  /* Prefix properties, e.g. `backdrop-filter` -> `-webkit-backdrop-filter` */
  const propertyFlags = cssPropertyPrefixFlags(property);
  if (propertyFlags & 0b001) cssText += `-webkit-${property}:${value};`;
  if (propertyFlags & 0b010) cssText += `-moz-${property}:${value};`;
  if (propertyFlags & 0b100) cssText += `-ms-${property}:${value};`;

  /* Prefix values, e.g. `position: "sticky"` -> `position: "-webkit-sticky"` */
  /* Notice that flags don't overlap and property prefixing isn't needed here */
  const valueFlags = cssValuePrefixFlags(property, value);
  if (valueFlags & 0b001) cssText += `${property}:-webkit-${value};`;
  else if (valueFlags & 0b010) cssText += `${property}:-moz-${value};`;
  else if (valueFlags & 0b100) cssText += `${property}:-ms-${value};`;

  /* Include the standardized declaration last */
  /* https://css-tricks.com/ordering-css3-properties/ */
  cssText += `${property}:${value};`;

  return cssText;
}

Prefix flags may be defined in TypeScript without any overhead as follows:

const enum CSSPrefixFlags {
  "-webkit-" = 1 << 0, // 0b001
     "-moz-" = 1 << 1, // 0b010
      "-ms-" = 1 << 2, // 0b100
}

/* Magic numbers from the previous snippet should be replaced like below: */
if (flags & CSSPrefixFlags["-webkit-"]) cssText += "...";
if (flags & CSSPrefixFlags["-moz-"]) cssText += "...";
if (flags & CSSPrefixFlags["-ms-"]) cssText += "...";

Browser Support

Every browser in the default Browserslist configuration is supported and tested against:

• Baidu Browser for Android 7.12+
• Chrome 57+
• Edge 16+
• Firefox 48+
• Internet Explorer 11
• KaiOS Browser 2.5+
• Opera 46+
• Safari 12.2+
• Samsung Internet Browser 11.1+
• QQ Browser for Android 10.4+
• UC Browser for Android 12.12+

Quirks

• Function values are only prefixed for longhand properties. This guarantees that only the start of each value is compared, for efficiency:

  // Prints "1 0"
  console.log(
    cssPropertyPrefixFlags(
      "background-image", // Longhand
      "image-set('example.png' 1x, 'example-2x.png' 2x)", // Prefixed
    ),
    cssPropertyPrefixFlags(
      "background", // Shorthand
      "image-set('example.png' 1x, 'example-2x.png' 2x)", // Not prefixed
    ),
  );

• CSS Grid works in IE 11 only when using the following longhand properties:

  • grid-template-rows, grid-template-columns
  • grid-row-start, grid-column-start
  • -ms-grid-row-span and -ms-grid-column-span (along with grid-row-end and grid-column-end for cross-browser compatibility)
  • align-self, justify-self

• cross-fade() and element() functions are not prefixed, due to the lack of standard implementations.

• Selectors are not yet supported.

Acknowledgements

This project was heavily inspired by tiny-css-prefixer. Test vectors are obtained from @mdn/browser-compat-data.