This release includes significant changes under the hood (such as a brand new parser!), but backwards compatibility has been a high priority. Most users should be able to upgrade without needing to make any changes (or with only minimal changes).

Added

• XML processing instructions are now included in parsed documents as XmlProcessingInstruction nodes (with the type value "pi"). Previously they were discarded.

• A new sortAttributes option. When true, attributes will be sorted in alphabetical order in an element's attributes object (which is no longer the default behavior).

• TypeScript type definitions. While parse-xml is still written in JavaScript, it now has TypeScript-friendly JSDoc comments throughout, with strict type checking enabled. These comments are now used to generate type definitions at build time.

Changed

• The minimum supported Node.js version is now 12.x, and the minimum supported ECMAScript version is ES2017. Extremely old browsers (like IE11) are no longer supported out of the box, but you can still transpile parse-xml yourself if you need to support old browsers.

• The XML parser has been completely rewritten with the primary goals of improving robustness and safety.

  While the previous parser was good, it relied heavily on complex regular expressions. This helped keep it extremely small, but also left it open to the possibility of regex denial of service bugs when parsing unusual or maliciously crafted input.

  The new parser uses a less interesting but overall safer approach, and employs regular expressions only sparingly and in ways that aren't risky (they're now only used as performance optimizations rather than as the basis for the entire parser).

• The parseXml() function now returns an XmlDocument instance instead of a plain object. Its properties are backwards compatible.

• Other node types (elements, text nodes, CDATA nodes, and comments) are also now represented by class instances (XmlElement, XmlText, XmlCdata, and XmlComment) rather than plain objects. Their properties are all backwards compatible.

• Attributes are no longer sorted alphabetically by name in an element's attributes object by default. They're now defined in the same order that they're encountered in the document being parsed, unless the sortAttributes parser option is true.

• If the value returned by an optional resolveUndefinedEntity function is not a string, null, or undefined, a TypeError will now be thrown. If you don't pass a custom resolveUndefinedEntity function to parseXml(), then this change won't affect you.

• Some error messages have been changed to improve clarity, and more helpful errors have been added in some scenarios that previously would have resulted in generic or less helpful errors.

• The browser field in package.json has been removed and the main field now points both Node.js and browser bundlers to the same untranspiled CommonJS source.

  When bundled using your favorite bundler, parse-xml will work great in all modern browsers with no transpilation needed. If you don't want to use a bundler, you can still use the prepackaged UMD bundle at dist/umd/parse-xml.min.js, which provides a parseXml global.