Fix crash when missing Google Task list

If user transferred Google Task metadata from a backup file created
prior to version 5.3 and did not re-enable Google Task synchronization
then the app won't be able to find a Google Task list

CHANGELOG.md

@@ -1,6 +1,10 @@
 Change Log
 ---
 
+### 6.0.1 (2018-04-23)
+
+* Fix crash caused by missing Google Task metadata
+
 ### 6.0 (2018-04-23)
 
 * Change to [annual subscription](http://tasks.org/subscribe) pricing

app/build.gradle

@@ -19,8 +19,8 @@ android {
     defaultConfig {
         testApplicationId "org.tasks.test"
         applicationId "org.tasks"
-        versionCode 525
-        versionName "6.0"
+        versionCode 526
+        versionName "6.0.1"
         targetSdkVersion 27
         minSdkVersion 15
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

app/src/main/java/org/tasks/tasklist/TagFormatter.java

@@ -120,9 +120,15 @@ public class TagFormatter {
   CharSequence getTagString(String caldav, String googleTask, List<String> tagUuids) {
     List<ColoredString> strings = new ArrayList<>();
     if (!Strings.isNullOrEmpty(googleTask)) {
-      strings.add(getGoogleTaskList(googleTask));
+      ColoredString googleTaskList = getGoogleTaskList(googleTask);
+      if (googleTaskList != null) {
+        strings.add(googleTaskList);
+      }
     } else if (!Strings.isNullOrEmpty(caldav)) {
-      strings.add(getCaldavCalendar(caldav));
+      ColoredString caldavCalendar = getCaldavCalendar(caldav);
+      if (caldavCalendar != null) {
+        strings.add(caldavCalendar);
+      }
     }
 
     Iterable<ColoredString> tags = filter(transform(tagUuids, uuidToTag), Predicates.notNull());
@@ -180,7 +186,10 @@ public class TagFormatter {
   private ColoredString getGoogleTaskList(String remoteId) {
     ColoredString googleTaskList = googleTaskLists.get(remoteId);
     if (googleTaskList == null) {
-      googleTaskList = new ColoredString(googleTaskListDao.getByRemoteId(remoteId));
+      GoogleTaskList byRemoteId = googleTaskListDao.getByRemoteId(remoteId);
+      if (byRemoteId != null) {
+        googleTaskList = new ColoredString(byRemoteId);
+      }
       googleTaskLists.put(remoteId, googleTaskList);
     }
     return googleTaskList;
@@ -189,7 +198,10 @@ public class TagFormatter {
   private ColoredString getCaldavCalendar(String uuid) {
     ColoredString calendar = caldavCalendars.get(uuid);
     if (calendar == null) {
-      calendar = new ColoredString(caldavDao.getCalendar(uuid));
+      CaldavCalendar byUuid = caldavDao.getCalendar(uuid);
+      if (byUuid != null) {
+        calendar = new ColoredString(byUuid);
+      }
       caldavCalendars.put(uuid, calendar);
     }
     return calendar;