Add missing rejection handling for Promises (#7008)

* Add eslint-plugin-promise to detect uncaught rejections

* Move alert generation for errors to actions/alert

* Add missing rejection handling for Promises

* Use catch() instead of onReject on then()

Then it will catches rejection from onFulfilled. This detection can be
disabled by `allowThen` option, though.

1 files changed, 22 insertions, 8 deletions

diff --git a/app/javascript/mastodon/storage/modifier.js b/app/javascript/mastodon/storage/modifier.js
index 1bec04d0f..4773d07a9 100644
--- a/app/javascript/mastodon/storage/modifier.js
+++ b/app/javascript/mastodon/storage/modifier.js
@@ -9,6 +9,12 @@ const limit = 1024;
 // https://webkit.org/status/#specification-service-workers
 const asyncCache = window.caches ? caches.open('mastodon-system') : Promise.reject();
 
+function printErrorIfAvailable(error) {
+  if (error) {
+    console.warn(error);
+  }
+}
+
 function put(name, objects, onupdate, oncreate) {
   return asyncDB.then(db => new Promise((resolve, reject) => {
     const putTransaction = db.transaction(name, 'readwrite');
@@ -77,7 +83,9 @@ function evictAccountsByRecords(records) {
 
     function evict(toEvict) {
       toEvict.forEach(record => {
-        asyncCache.then(cache => accountAssetKeys.forEach(key => cache.delete(records[key])));
+        asyncCache
+          .then(cache => accountAssetKeys.forEach(key => cache.delete(records[key])))
+          .catch(printErrorIfAvailable);
 
         accountsMovedIndex.getAll(record.id).onsuccess = ({ target }) => evict(target.result);
 
@@ -90,11 +98,11 @@ function evictAccountsByRecords(records) {
     }
 
     evict(records);
-  });
+  }).catch(printErrorIfAvailable);
 }
 
 export function evictStatus(id) {
-  return evictStatuses([id]);
+  evictStatuses([id]);
 }
 
 export function evictStatuses(ids) {
@@ -110,7 +118,7 @@ export function evictStatuses(ids) {
       idIndex.getKey(id).onsuccess =
         ({ target }) => target.result && store.delete(target.result);
     });
-  });
+  }).catch(printErrorIfAvailable);
 }
 
 function evictStatusesByRecords(records) {
@@ -127,7 +135,9 @@ export function putAccounts(records) {
         const oldURL = target.result[key];
 
         if (newURL !== oldURL) {
-          asyncCache.then(cache => cache.delete(oldURL));
+          asyncCache
+            .then(cache => cache.delete(oldURL))
+            .catch(printErrorIfAvailable);
         }
       });
 
@@ -145,10 +155,14 @@ export function putAccounts(records) {
     oncomplete();
   }).then(records => {
     evictAccountsByRecords(records);
-    asyncCache.then(cache => cache.addAll(newURLs));
-  });
+    asyncCache
+      .then(cache => cache.addAll(newURLs))
+      .catch(printErrorIfAvailable);
+  }).catch(printErrorIfAvailable);
 }
 
 export function putStatuses(records) {
-  put('statuses', records).then(evictStatusesByRecords);
+  put('statuses', records)
+    .then(evictStatusesByRecords)
+    .catch(printErrorIfAvailable);
 }