Implement PR feedback

Author: ueman

dart/lib/src/environment_variables.dart

@@ -14,8 +14,13 @@ void setEnvironmentVariables(SentryOptions options, EnvironmentVariables vars) {
   // options has precendence over vars
   options.dsn = options.dsn ?? vars.dsn;
 
+  var environment = options.platformChecker.environment;
+  options.environment = options.environment ?? environment;
+
   // vars has precedence over options
   options.environment = vars.environment ?? options.environment;
+
+  // vars has precedence over options
   options.release = vars.release ?? options.release;
   options.dist = vars.dist ?? options.dist;
 }

dart/lib/src/platform_checker.dart

@@ -1,4 +1,4 @@
-import '../sentry.dart';
+import 'sentry_options.dart';
 
 /// Helper to check in which enviroment the library is running.
 /// The envirment checks (release/debug/profile) are mutually exclusive.

dart/lib/src/sentry_options.dart

@@ -15,10 +15,11 @@ import 'platform_checker.dart';
 /// Default Environment is none is set
 const defaultEnvironment = 'production';
 
-/// Sentry SDK options
 // TODO: Scope observers, enableScopeSync
 // TODO: shutdownTimeout, flushTimeoutMillis
 // https://api.dart.dev/stable/2.10.2/dart-io/HttpClient/close.html doesn't have a timeout param, we'd need to implement manually
+
+/// Sentry SDK options
 class SentryOptions {
   /// Default Log level if not specified Default is DEBUG
   static final SentryLevel _defaultDiagnosticLevel = SentryLevel.debug;

flutter/lib/src/default_integrations.dart

@@ -340,8 +340,7 @@ class LoadAndroidImageListIntegration
 /// a PackageInfo wrapper to make it testable
 typedef PackageLoader = Future<PackageInfo> Function();
 
-/// an Integration that loads the Release version from Native Apps
-/// or SENTRY_RELEASE and SENTRY_DIST variables
+/// An [Integration] that loads the release version from native apps
 class LoadReleaseIntegration extends Integration<SentryFlutterOptions> {
   final PackageLoader _packageLoader;
 
@@ -350,7 +349,7 @@ class LoadReleaseIntegration extends Integration<SentryFlutterOptions> {
   @override
   FutureOr<void> call(Hub hub, SentryFlutterOptions options) async {
     try {
-      // For web we read the environment variables in sentry_dart
+      // For non Flutter apps, we read the environment variables in sentry_dart
       if (!kIsWeb) {
         final packageInfo = await _packageLoader();
         final release =