warning(condition,format) condition为否值时报错,从第三个参数开始字符串替换format中的"%s"
'use strict'; var emptyFunction = require('./emptyFunction'); // condition为否值,format中%s转化为剩余参数,通过console.error打印错误文本或直接报错 var warning = emptyFunction; if (process.env.NODE_ENV !== 'production') { (function () { var printWarning = function printWarning(format) { for (var _len = arguments.length, args = Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) { args[_key - 1] = arguments[_key]; } var argIndex = 0; var message = 'Warning: ' + format.replace(/%s/g, function () { return args[argIndex++]; }); if (typeof console !== 'undefined') { console.error(message); } try { throw new Error(message); } catch (x) {} }; warning = function warning(condition, format) { if (format === undefined) { throw new Error('`warning(condition, format, ...args)` requires a warning ' + 'message argument'); } if (format.indexOf('Failed Composite propType: ') === 0) { return; } if (!condition) { for (var _len2 = arguments.length, args = Array(_len2 > 2 ? _len2 - 2 : 0), _key2 = 2; _key2 < _len2; _key2++) { args[_key2 - 2] = arguments[_key2]; } printWarning.apply(undefined, [format].concat(args)); } }; })(); } module.exports = warning;