packages/hast-util-to-babel-ast/src/stringToObjectStyle.js
function formatKey(key) {
  key = key.toLowerCase()
  // Don't capitalize -ms- prefix
  if (/^-ms-/.test(key)) key = key.substr(1)
  return t.identifier(hyphenToCamelCase(key))
}
function formatKey(key) {
  key = key.toLowerCase()
  // Don't capitalize -ms- prefix
  if (/^-ms-/.test(key)) key = key.substr(1)
  return t.identifier(hyphenToCamelCase(key))
}
function formatKey ( key ) { key = key . toLowerCase ( ) // Don't capitalize -ms- prefix if ( / ^-ms- / . test ( key ) ) key = key . substr ( 1 ) return t . identifier ( hyphenToCamelCase ( key ) ) }
Format style key into JSX style object key.

@param {string} key
@return {string}
Format style key into JSX style object key .