Upgrade minimum SDK to 3.4 as stack_trace will need it anyway.

Author: isoos

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## 3.4.9
 
 - Better exception stacktraces (in some cases) using `package:stack_trace`.
+- With that dependency, upgraded minimum SDK to `3.4`.
 
 ## 3.4.8
 

lib/src/messages/client_messages.dart

@@ -66,11 +66,11 @@ class StartupMessage extends ClientMessage {
       (e('client_encoding'), buffer.encodingName),
       (e('database'), e(_databaseName)),
       (e('TimeZone'), e(_timeZone)),
-      if (_username != null) (e('user'), e(_username!)),
+      if (_username != null) (e('user'), e(_username)),
       if (_replication != ReplicationMode.none.value)
         (e('replication'), e(_replication)),
       if (_applicationName != null)
-        (e('application_name'), e(_applicationName!)),
+        (e('application_name'), e(_applicationName)),
     ];
 
     final propertiesLength = properties

lib/src/v3/connection.dart

@@ -844,7 +844,7 @@ class _PgResultStreamSubscription
   StackTrace _trace() => Chain([
         Trace.current(1),
         _callerTrace,
-        if (_parentTrace != null) _parentTrace!,
+        if (_parentTrace != null) _parentTrace,
       ]);
 
   @override

pubspec.yaml

@@ -9,7 +9,7 @@ topics:
   - postgres
 
 environment:
-  sdk: '>=3.0.0 <4.0.0'
+  sdk: '>=3.4.0 <4.0.0'
 
 dependencies:
   buffer: ^1.2.2