mirror of https://github.com/lukechilds/node.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
35 lines
1.2 KiB
35 lines
1.2 KiB
var stringToArray = require('./_stringToArray'),
|
|
toString = require('./toString');
|
|
|
|
/** Used to compose unicode character classes. */
|
|
var rsAstralRange = '\\ud800-\\udfff',
|
|
rsComboMarksRange = '\\u0300-\\u036f\\ufe20-\\ufe23',
|
|
rsComboSymbolsRange = '\\u20d0-\\u20f0',
|
|
rsVarRange = '\\ufe0e\\ufe0f';
|
|
|
|
/** Used to compose unicode capture groups. */
|
|
var rsZWJ = '\\u200d';
|
|
|
|
/** Used to detect strings with [zero-width joiners or code points from the astral planes](http://eev.ee/blog/2015/09/12/dark-corners-of-unicode/). */
|
|
var reHasComplexSymbol = RegExp('[' + rsZWJ + rsAstralRange + rsComboMarksRange + rsComboSymbolsRange + rsVarRange + ']');
|
|
|
|
/**
|
|
* Creates a function like `_.lowerFirst`.
|
|
*
|
|
* @private
|
|
* @param {string} methodName The name of the `String` case method to use.
|
|
* @returns {Function} Returns the new function.
|
|
*/
|
|
function createCaseFirst(methodName) {
|
|
return function(string) {
|
|
string = toString(string);
|
|
|
|
var strSymbols = reHasComplexSymbol.test(string) ? stringToArray(string) : undefined,
|
|
chr = strSymbols ? strSymbols[0] : string.charAt(0),
|
|
trailing = strSymbols ? strSymbols.slice(1).join('') : string.slice(1);
|
|
|
|
return chr[methodName]() + trailing;
|
|
};
|
|
}
|
|
|
|
module.exports = createCaseFirst;
|
|
|