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-rw-r--r--node_modules/is-generator-function/index.js32
1 files changed, 32 insertions, 0 deletions
diff --git a/node_modules/is-generator-function/index.js b/node_modules/is-generator-function/index.js
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+++ b/node_modules/is-generator-function/index.js
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+'use strict';
+
+var toStr = Object.prototype.toString;
+var fnToStr = Function.prototype.toString;
+var isFnRegex = /^\s*(?:function)?\*/;
+var hasToStringTag = typeof Symbol === 'function' && typeof Symbol.toStringTag === 'symbol';
+var getProto = Object.getPrototypeOf;
+var getGeneratorFunc = function () { // eslint-disable-line consistent-return
+ if (!hasToStringTag) {
+ return false;
+ }
+ try {
+ return Function('return function*() {}')();
+ } catch (e) {
+ }
+};
+var generatorFunc = getGeneratorFunc();
+var GeneratorFunction = generatorFunc ? getProto(generatorFunc) : {};
+
+module.exports = function isGeneratorFunction(fn) {
+ if (typeof fn !== 'function') {
+ return false;
+ }
+ if (isFnRegex.test(fnToStr.call(fn))) {
+ return true;
+ }
+ if (!hasToStringTag) {
+ var str = toStr.call(fn);
+ return str === '[object GeneratorFunction]';
+ }
+ return getProto(fn) === GeneratorFunction;
+};