Catch missing host permission error for restricted pages such as AMO. F…

…ix #69.

src/_locales/en/messages.json

@@ -7,6 +7,7 @@
     "message": "Copy ShortURL for this link",
     "description": "Context menu item label text for link."
   },
+
   "shorten_error": {
     "message": "ZOMG, error creating short URL.",
     "description": "Error message when shortening URL was unsuccessful."
@@ -15,6 +16,10 @@
     "message": "No API key in preferences.",
     "description": "Error message when shortening service needs an API key and none was provided."
   },
+  "error_host_permission": {
+    "message": "Sorry, Copy ShortURL cannot run on pages restricted by the browser.",
+    "description": "Error message when running on about: or addons.mozilla.org."
+  },
 
   "service_title": {
     "message": "URL Shortening Service",

src/lib/main.js

@@ -1,3 +1,4 @@
+import notify from './notify';
 import processUrl from './shortener';
 
 const _ = browser.i18n.getMessage;
@@ -51,6 +52,12 @@ browser.commands.onCommand.addListener((cmd) => {
 function discoverUrl() {
   browser.tabs.executeScript({
     file: '/data/js/find-short-url.js'
+  }).catch(e => {
+    if (e.message && /Missing host permission for the tab/.test(e.message)) {
+      notify(_('error_host_permission'));
+    } else {
+      throw e;
+    }
   });
 }
 browser.runtime.onMessage.addListener(processUrl);

src/manifest.json

@@ -3,7 +3,7 @@
   "description": "Detect or create a short URL for the current page.",
   "author": "Fred Wenzel",
   "homepage_url": "http://copy-shorturl.rtfd.org",
-  "version": "4.0.1",
+  "version": "4.0.2",
   "default_locale": "en",
   "icons": {
     "16": "data/img/icon-16.png",