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-rw-r--r--deps/npm/node_modules/is-regex/index.js39
1 files changed, 39 insertions, 0 deletions
diff --git a/deps/npm/node_modules/is-regex/index.js b/deps/npm/node_modules/is-regex/index.js
new file mode 100644
index 0000000000..be6513390f
--- /dev/null
+++ b/deps/npm/node_modules/is-regex/index.js
@@ -0,0 +1,39 @@
+'use strict';
+
+var has = require('has');
+var regexExec = RegExp.prototype.exec;
+var gOPD = Object.getOwnPropertyDescriptor;
+
+var tryRegexExecCall = function tryRegexExec(value) {
+ try {
+ var lastIndex = value.lastIndex;
+ value.lastIndex = 0;
+
+ regexExec.call(value);
+ return true;
+ } catch (e) {
+ return false;
+ } finally {
+ value.lastIndex = lastIndex;
+ }
+};
+var toStr = Object.prototype.toString;
+var regexClass = '[object RegExp]';
+var hasToStringTag = typeof Symbol === 'function' && typeof Symbol.toStringTag === 'symbol';
+
+module.exports = function isRegex(value) {
+ if (!value || typeof value !== 'object') {
+ return false;
+ }
+ if (!hasToStringTag) {
+ return toStr.call(value) === regexClass;
+ }
+
+ var descriptor = gOPD(value, 'lastIndex');
+ var hasLastIndexDataProperty = descriptor && has(descriptor, 'value');
+ if (!hasLastIndexDataProperty) {
+ return false;
+ }
+
+ return tryRegexExecCall(value);
+};