Prevent multiple attempts to resolve the same Promise

Author: wojtekmaj

src/every.js

@@ -1,20 +1,26 @@
 import asyncForEach from './forEach';
 
 export default function asyncSome(arr, fn) {
+  let resolved;
   return new Promise((resolve) => {
     asyncForEach(
       arr,
       (cur, idx, arr2) =>
         new Promise((resolve2) => {
+          if (resolved) {
+            return;
+          }
           fn(cur, idx, arr2).then((result) => {
             if (!result) {
               resolve(false);
+              resolved = true;
             }
             resolve2();
           });
         }),
     ).then(() => {
       resolve(true);
+      resolved = true;
     });
   });
 }

src/every_strict.js

@@ -1,20 +1,26 @@
 import asyncForEachStrict from './forEach_strict';
 
 export default function asyncEveryStrict(arr, fn) {
+  let resolved;
   return new Promise((resolve) => {
     asyncForEachStrict(
       arr,
       (cur, idx, arr2) =>
         new Promise((resolve2) => {
+          if (resolved) {
+            return;
+          }
           fn(cur, idx, arr2).then((result) => {
             if (!result) {
               resolve(false);
+              resolved = true;
             }
             resolve2();
           });
         }),
     ).then(() => {
       resolve(true);
+      resolved = true;
     });
   });
 }

src/some.js

@@ -1,20 +1,26 @@
 import asyncForEach from './forEach';
 
 export default function asyncSome(arr, fn) {
+  let resolved;
   return new Promise((resolve) => {
     asyncForEach(
       arr,
       (cur, idx, arr2) =>
         new Promise((resolve2) => {
+          if (resolved) {
+            return;
+          }
           fn(cur, idx, arr2).then((result) => {
             if (result) {
               resolve(true);
+              resolved = true;
             }
             resolve2();
           });
         }),
     ).then(() => {
       resolve(false);
+      resolved = true;
     });
   });
 }

src/some_strict.js

@@ -1,20 +1,26 @@
 import asyncForEachStrict from './forEach_strict';
 
 export default function asyncSomeStrict(arr, fn) {
+  let resolved;
   return new Promise((resolve) => {
     asyncForEachStrict(
       arr,
       (cur, idx, arr2) =>
         new Promise((resolve2) => {
+          if (resolved) {
+            return;
+          }
           fn(cur, idx, arr2).then((result) => {
             if (result) {
               resolve(true);
+              resolved = true;
             }
             resolve2();
           });
         }),
     ).then(() => {
       resolve(false);
+      resolved = true;
     });
   });
 }