[firebase-crashlytics] Fixes exception when trying to format crash re…

…ason when the crash has no context (firebase#1931)

packages/firebase_crashlytics/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.1.0+2
+
+* [iOS] Fixes crash when trying to report a crash without any context
+
 ## 0.1.0+1
 
 * Added additional exception information from the Flutter framework to the reports.

packages/firebase_crashlytics/ios/Classes/FirebaseCrashlyticsPlugin.m

@@ -76,11 +76,16 @@ - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result
     for (NSDictionary *errorElement in errorElements) {
       [frames addObject:[self generateFrame:errorElement]];
     }
-    [[Crashlytics sharedInstance]
-        recordCustomExceptionName:call.arguments[@"exception"]
-                           reason:[NSString
-                                      stringWithFormat:@"thrown %s", call.arguments[@"context"]]
-                       frameArray:frames];
+
+    NSString *context = call.arguments[@"context"];
+    NSString *reason;
+    if (context != nil) {
+      reason = [NSString stringWithFormat:@"thrown %@", context];
+    }
+
+    [[Crashlytics sharedInstance] recordCustomExceptionName:call.arguments[@"exception"]
+                                                     reason:reason
+                                                 frameArray:frames];
     result(@"Error reported to Crashlytics.");
   } else if ([@"Crashlytics#isDebuggable" isEqualToString:call.method]) {
     result([NSNumber numberWithBool:[Crashlytics sharedInstance].debugMode]);

packages/firebase_crashlytics/pubspec.yaml

@@ -2,7 +2,7 @@ name: firebase_crashlytics
 description:
   Flutter plugin for Firebase Crashlytics. It reports uncaught errors to the
   Firebase console.
-version: 0.1.0+1
+version: 0.1.0+2
 author: Flutter Team <[email protected]>
 homepage: https://github.com/flutter/plugins/tree/master/packages/firebase_crashlytics