1 files changed, 37 insertions, 0 deletions
diff --git a/lib/internal/createTester.js b/lib/internal/createTester.js
new file mode 100644
index 0000000..0e9e750
--- /dev/null
+++ b/lib/internal/createTester.js
@@ -0,0 +1,37 @@
+'use strict';
+
+export default function _createTester(eachfn, check, getResult) {
+    return function(arr, limit, iterator, cb) {
+        function done(err) {
+            if (cb) {
+                if (err) {
+                    cb(err);
+                } else {
+                    cb(null, getResult(false, void 0));
+                }
+            }
+        }
+        function iteratee(x, _, callback) {
+            if (!cb) return callback();
+            iterator(x, function (err, v) {
+                if (cb) {
+                    if (err) {
+                        cb(err);
+                        cb = iterator = false;
+                    } else if (check(v)) {
+                        cb(null, getResult(true, x));
+                        cb = iterator = false;
+                    }
+                }
+                callback();
+            });
+        }
+        if (arguments.length > 3) {
+            eachfn(arr, limit, iteratee, done);
+        } else {
+            cb = iterator;
+            iterator = limit;
+            eachfn(arr, iteratee, done);
+        }
+    };
+}