Issue 5549 - Implement missing error handlings for custom filter lists

desktop-options.js

Index: desktop-options.js
===================================================================
--- a/desktop-options.js
+++ b/desktop-options.js
@@ -547,14 +547,17 @@
     return null;
   }
 
-  function sendMessageHandleErrors(message, onSuccess)
+  function sendMessageHandleErrors(message, callback)
   {
     browser.runtime.sendMessage(message, (errors) =>
     {
-      if (errors.length > 0)
-        alert(errors.join("\n"));
-      else if (onSuccess)
-        onSuccess();
+      if (callback)
+      {
+        if (errors.length > 0)
+          callback(errors);
+        else
+          callback();
+      }
     });
   }
 
@@ -648,14 +651,35 @@
         });
         break;
       case "save-custom-filters":
+        const filters = E("custom-filters-raw");
+        const filtersValue = filters.value;
         sendMessageHandleErrors({
           type: "filters.importRaw",
-          text: E("custom-filters-raw").value,
+          text: filtersValue,
           removeExisting: true
         },
-        () =>
+        (errors) =>
         {
-          setCustomFiltersView("read");
+          if (errors)
+          {
+            E("custom-filters").classList.add("warning");
+            const lines = filtersValue.split(/\n+|\n\s+\n/);
+            const info = errors.map(error => lines[error.lineno - 1]);
+            const editFilters = E("custom-filters-edit-filters");
+            info.forEach(
+              message =>
+              {
+                const li = document.createElement("li");
+                editFilters.appendChild(li).textContent = message;
+              }
+            );
+            if (errors.length > 5)
+              editFilters.classList.add("many");
+          }
+          else
+          {
+            setCustomFiltersView("read");
+          }
         });
         break;
       case "show-more-filters-section":
@@ -755,6 +779,10 @@
     updateCustomFiltersUi();
     if (mode == "read")
     {
+      E("custom-filters").classList.remove("warning");
+      const editFilters = E("custom-filters-edit-filters");
+      editFilters.textContent = "";
+      editFilters.classList.remove("many");
       customFiltersElement.disabled = true;
       if (!customFiltersElement.value)
       {
@@ -918,10 +946,10 @@
     {
       setLinks("enable-acceptable-ads-description", link);
     });
-    setElementText(E("tracking-warning-1"), "options_tracking_warning_1", 
+    setElementText(E("tracking-warning-1"), "options_tracking_warning_1",
       [getMessage("common_feature_privacy_title"),
-      getMessage("options_acceptableAds_ads_label")]);
-    setElementText(E("tracking-warning-3"), "options_tracking_warning_3", 
+       getMessage("options_acceptableAds_ads_label")]);
+    setElementText(E("tracking-warning-3"), "options_tracking_warning_3",
       [getMessage("options_acceptableAds_privacy_label")]);
 
     getDocLink("privacy_friendly_ads", (link) =>
@@ -964,6 +992,7 @@
     getDocLink("filterdoc", (link) =>
     {
       E("link-filters").setAttribute("href", link);
+      E("link-filters-on-edit-error").setAttribute("href", link);
     });
 
     getDocLink("subscriptions", (link) =>
@@ -1295,7 +1324,7 @@
         updateSubscription(subscription);
         break;
       case "added":
-        let {url, recommended} = subscription;
+        let {url} = subscription;
         // Handle custom subscription
         if (/^~user/.test(url))
         {