Fix a few notices

lib/models/post.dart

@@ -58,22 +58,13 @@ class Post implements LikeElement {
       required this.access,
       required this.comments,
       required this.survey})
-      : assert(id != null),
-        assert(userID != null),
-        assert(userPageID != 0 || groupID != 0),
-        assert(timeSent != null),
-        assert(kind != PostKind.TEXT || content != null),
-        assert(visibilityLevel != null),
-        assert(kind != null),
+      : assert(userPageID != 0 || groupID != 0),
         assert(kind != PostKind.COUNTDOWN || timeEnd != null),
-        assert(kind != PostKind.SURVEY || survey != null),
-        assert(likes != null),
-        assert(userLike != null),
-        assert(access != null);
+        assert(kind != PostKind.SURVEY || survey != null);
 
   bool get isGroupPost => groupID != null && groupID! > 0;
 
-  bool get hasContent => content != null && !content.isNull;
+  bool get hasContent => !content.isNull && !content.isEmpty;
 
   bool get hasComments => comments != null;
 

lib/models/res_check_password_reset_token.dart

@@ -1,5 +1,3 @@
-
-
 /// Check password reset token result
 ///
 /// @author Pierre Hubert
@@ -13,7 +11,5 @@ class ResCheckPasswordToken {
     required this.firstName,
     required this.lastName,
     required this.email,
-  })  : assert(firstName != null),
-        assert(lastName != null),
-        assert(email != null);
+  });
 }

lib/models/search_result.dart

@@ -1,5 +1,3 @@
-
-
 /// Single search result
 ///
 /// @author Pierre Hubert
@@ -13,6 +11,5 @@ class SearchResult {
   SearchResult({
     required this.id,
     required this.kind,
-  })  : assert(id != null),
-        assert(kind != null);
+  });
 }

lib/models/security_settings.dart

@@ -1,5 +1,3 @@
-
-
 /// Security settings of the user
 ///
 /// @author Pierre HUBERT
@@ -15,8 +13,5 @@ class SecuritySettings {
     required this.securityAnswer1,
     required this.securityQuestion2,
     required this.securityAnswer2,
-  })  : assert(securityQuestion1 != null),
-        assert(securityAnswer1 != null),
-        assert(securityQuestion2 != null),
-        assert(securityAnswer2 != null);
+  });
 }

lib/models/server_config.dart

@@ -35,14 +35,7 @@ class PasswordPolicy {
     required this.minNumberDigits,
     required this.minNumberSpecialCharacters,
     required this.minCategoriesPresence,
-  })  : assert(allowMailInPassword != null),
-        assert(allowNameInPassword != null),
-        assert(minPasswordLength != null),
-        assert(minNumberUpperCaseLetters != null),
-        assert(minNumberLowerCaseLetters != null),
-        assert(minNumberDigits != null),
-        assert(minNumberSpecialCharacters != null),
-        assert(minCategoriesPresence != null);
+  });
 }
 
 class ServerDataConservationPolicy {
@@ -60,12 +53,7 @@ class ServerDataConservationPolicy {
     required this.minPostsLifetime,
     required this.minConversationMessagesLifetime,
     required this.minLikesLifetime,
-  })  : assert(minInactiveAccountLifetime != null),
-        assert(minNotificationLifetime != null),
-        assert(minCommentsLifetime != null),
-        assert(minPostsLifetime != null),
-        assert(minConversationMessagesLifetime != null),
-        assert(minLikesLifetime != null);
+  });
 }
 
 class ConversationsPolicy {
@@ -97,19 +85,7 @@ class ConversationsPolicy {
     required this.maxThumbnailHeight,
     required this.maxLogoWidth,
     required this.maxLogoHeight,
-  })  : assert(maxConversationNameLen != null),
-        assert(minMessageLen != null),
-        assert(maxMessageLen != null),
-        assert(allowedFilesType != null),
-        assert(filesMaxSize != null),
-        assert(writingEventInterval != null),
-        assert(writingEventLifetime != null),
-        assert(maxMessageImageWidth != null),
-        assert(maxMessageImageHeight != null),
-        assert(maxThumbnailWidth != null),
-        assert(maxThumbnailHeight != null),
-        assert(maxLogoWidth != null),
-        assert(maxLogoHeight != null);
+  });
 }
 
 class AccountInformationPolicy {
@@ -125,11 +101,7 @@ class AccountInformationPolicy {
     required this.minLastNameLength,
     required this.maxLastNameLength,
     required this.maxLocationLength,
-  })  : assert(minFirstNameLength != null),
-        assert(maxFirstNameLength != null),
-        assert(minLastNameLength != null),
-        assert(maxLastNameLength != null),
-        assert(maxLocationLength != null);
+  });
 }
 
 enum BannerNature { Information, Warning, Success }
@@ -161,9 +133,7 @@ class Banner {
     required this.nature,
     required this.message,
     required this.link,
-  })  : assert(enabled != null),
-        assert(nature != null),
-        assert(message != null);
+  });
 
   bool get visible => enabled && (expire == null || expire! > time());
 }
@@ -195,15 +165,5 @@ class ServerConfig {
     required this.dataConservationPolicy,
     required this.conversationsPolicy,
     required this.accountInformationPolicy,
-  })  : assert(minSupportedMobileVersion != null),
-        assert(termsURL != null),
-        assert(privacyPolicyURL != null),
-        assert(contactEmail != null),
-        assert(playStoreURL != null),
-        assert(androidDirectDownloadURL != null),
-        assert(notificationsPolicy != null),
-        assert(passwordPolicy != null),
-        assert(dataConservationPolicy != null),
-        assert(conversationsPolicy != null),
-        assert(accountInformationPolicy != null);
+  });
 }

lib/models/survey_choice.dart

@@ -1,5 +1,3 @@
-
-
 /// Single survey choice
 ///
 /// @author Pierre HUBERT
@@ -13,7 +11,5 @@ class SurveyChoice {
     required this.id,
     required this.name,
     required this.responses,
-  })  : assert(id != null),
-        assert(name != null),
-        assert(responses != null);
+  });
 }

lib/models/unread_conversation.dart

@@ -12,6 +12,5 @@ class UnreadConversation {
   const UnreadConversation({
     required this.conv,
     required this.message,
-  })  : assert(conv != null),
-        assert(message != null);
+  });
 }

lib/models/ws_message.dart

@@ -13,9 +13,7 @@ class WsMessage {
     required this.id,
     required this.title,
     required this.data,
-  })  : assert(id != null),
-        assert(title != null),
-        assert(title.length > 0);
+  }) : assert(title.length > 0);
 
   /// Construct a message from a JSON document (messages coming from the server)
   static WsMessage fromJSON(final Map<dynamic, dynamic> m) {
@@ -23,12 +21,11 @@ class WsMessage {
   }
 
   /// Turn a message into a JSON object to send it to the API
-  String toJSON() =>
-      jsonEncode({
+  String toJSON() => jsonEncode({
         "id": id,
         "title": title,
         "data": data,
       });
 
-  bool get hasId => this.id != null && this.id.isNotEmpty;
+  bool get hasId => this.id.isNotEmpty;
 }