Utilize nonNulls where possible (#8043)

app/lib/account/models.dart

@@ -415,8 +415,7 @@ String consentDedupId({
   required List<String> args,
 }) =>
     [fromAgentId, email, kind, ...args]
-        .where((s) => s != null)
-        .whereType<String>()
+        .nonNulls
         .map(Uri.encodeComponent)
         .join('/');
 

app/lib/admin/backend.dart

@@ -573,8 +573,7 @@ class AdminBackend {
   }
 
   List<api.AdminUserEntry> _convertUsers(Iterable<User?> users) {
-    return users
-        .whereType<User>()
+    return users.nonNulls
         .where((u) => !u.isDeleted)
         .map(
           (u) => api.AdminUserEntry(

app/lib/fake/tool/init_data_file.dart

@@ -58,7 +58,7 @@ class FakeInitDataFileCommand extends Command {
         r.toString(),
         r.error,
         r.stackTrace?.toString(),
-      ].where((e) => e != null).join(' '));
+      ].nonNulls.join(' '));
     });
 
     final analysis = argResults!['analysis'] as String;

app/lib/frontend/handlers/account.dart

@@ -15,7 +15,6 @@ import '../../account/session_cookie.dart' as session_cookie;
 import '../../audit/backend.dart';
 import '../../frontend/request_context.dart';
 import '../../package/backend.dart';
-import '../../package/models.dart';
 import '../../publisher/backend.dart';
 import '../../publisher/models.dart';
 import '../../scorecard/backend.dart';
@@ -283,7 +282,7 @@ Future<shelf.Response> accountPackagesPageHandler(shelf.Request request) async {
         .lookupUserById(requestContext.authenticatedUserId!))!,
     userSessionData: requestContext.sessionData!,
     startPackage: next,
-    packageHits: hits.whereType<PackageView>().toList(),
+    packageHits: hits.nonNulls.toList(),
     nextPackage: page.nextPackage,
   );
   return htmlResponse(html);

app/lib/frontend/handlers/custom_api.dart

@@ -140,7 +140,7 @@ Future<shelf.Response> apiPackagesHandler(shelf.Request request) async {
     final packagesJson = [];
 
     final uri = activeConfiguration.primaryApiUri;
-    for (final version in pageVersions.whereType<PackageVersion>()) {
+    for (final version in pageVersions.nonNulls) {
       final versionString = Uri.encodeComponent(version.version!);
       final packageString = Uri.encodeComponent(version.package);
 

app/lib/frontend/templates/package_misc.dart

@@ -58,7 +58,7 @@ d.Node tagsNodeFromPackageView({
 }) {
   searchForm ??= SearchForm();
   final tags = package.tags;
-  final sdkTags = tags.where((s) => s.startsWith('sdk:')).toSet().toList();
+  final sdkTags = tags.where((s) => s.startsWith('sdk:')).toSet();
   final simpleTags = <SimpleTag>[];
   final badgeTags = <BadgeTag>[];
   d.Node? discontinuedNode;

app/lib/package/backend.dart

@@ -725,8 +725,8 @@ class PackageBackend {
     final newPublisherAdminEmails =
         await publisherBackend.getAdminMemberEmails(request.publisherId!);
     final allAdminEmails = <String>{
-      ...preTxUploaderEmails.whereType<String>(),
-      ...newPublisherAdminEmails.whereType<String>(),
+      ...preTxUploaderEmails,
+      ...newPublisherAdminEmails.nonNulls,
     };
 
     OutgoingEmail? email;
@@ -1440,7 +1440,7 @@ class PackageBackend {
     final emails = package.publisherId == null
         ? await accountBackend.getEmailsOfUserIds(package.uploaders!)
         : await publisherBackend.getAdminMemberEmails(package.publisherId!);
-    final existingEmails = emails.whereType<String>().toList();
+    final existingEmails = emails.nonNulls.toList();
     if (existingEmails.isEmpty) {
       // should not happen
       throw AssertionError(

app/lib/package/search_adapter.dart

@@ -47,11 +47,8 @@ class SearchAdapter {
       form,
       result!.totalCount,
       sdkLibraryHits: result.sdkLibraryHits,
-      packageHits: result.packageHits
-          .map((h) => views[h.package])
-          .where((v) => v != null)
-          .cast<PackageView>()
-          .toList(),
+      packageHits:
+          result.packageHits.map((h) => views[h.package]).nonNulls.toList(),
       errorMessage: result.errorMessage,
       statusCode: result.statusCode,
     );

app/lib/publisher/backend.dart

@@ -110,9 +110,8 @@ class PublisherBackend {
         // - search using this for query parameters
         _logger.shout('A user has more than 100 publishers.');
       }
-      final publishers = (await _db.lookup<Publisher>(publisherKeys))
-          .whereType<Publisher>()
-          .toList();
+      final publishers =
+          (await _db.lookup<Publisher>(publisherKeys)).nonNulls.toList();
       publishers.sort((a, b) => a.publisherId.compareTo(b.publisherId));
       return PublisherPage(
         publishers: publishers

app/lib/service/youtube/backend.dart

@@ -165,7 +165,7 @@ class _PkgOfWeekVideoFetcher {
             }
             return null;
           },
-        ).whereType<PkgOfWeekVideo>());
+        ).nonNulls);
         // next page
         nextPageToken = rs.nextPageToken;
         check = nextPageToken != null && nextPageToken.isNotEmpty;

pkg/api_builder/lib/src/client_library_generator.dart

@@ -113,12 +113,7 @@ code.Method _buildClientMethod(
   Handler h,
 ) {
   // Find url parameters
-  final params = _parser
-      .allMatches(h.route)
-      .map((m) => m[2])
-      .where((p) => p != null)
-      .cast<String>()
-      .toList();
+  final params = _parser.allMatches(h.route).map((m) => m[2]).nonNulls.toList();
   // Create a url pattern that embeds parameters above
   final urlPattern = h.route.replaceAllMapped(
     _parser,

pkg/code_coverage/lib/format_lcov.dart

@@ -54,7 +54,7 @@ Future main() async {
             !e.key.startsWith('pkg/code_coverage/') &&
             !e.key.startsWith('pkg/fake_gcloud/') &&
             !e.key.startsWith('pkg/pub_integration/'))
-  ].whereType<Entry>();
+  ].nonNulls;
   final pubDevEntry = Entry('pub-dev')
     ..covered = libEntries.map((e) => e.covered).reduce((a, b) => a + b)
     ..total = libEntries.map((e) => e.total).reduce((a, b) => a + b);
@@ -83,7 +83,7 @@ Future main() async {
 
   final uncoveredRanges = _lineExecCounts.keys
       .map((path) => _topUncoveredRange(path, _lineExecCounts[path]!))
-      .whereType<_UncoveredRange>()
+      .nonNulls
       .where((u) => u.codeLineCount > 0)
       .toList()
     ..sort((a, b) => -a.codeLineCount.compareTo(b.codeLineCount));

pkg/pub_package_reader/lib/pub_package_reader.dart

@@ -208,9 +208,7 @@ Future<PackageSummary> summarizePackageArchive(
   String? licensePath = tar.firstMatchingFileNameOrNull(licenseFileNames);
 
   final contentBytes = await tar.scanAndReadFiles(
-    [readmePath, changelogPath, examplePath, licensePath]
-        .whereType<String>()
-        .toList(),
+    [readmePath, changelogPath, examplePath, licensePath].nonNulls.toList(),
     maxLength: maxContentLength,
   );
 
@@ -439,8 +437,7 @@ Iterable<ArchiveIssue> checkStrictVersions(Pubspec pubspec) sync* {
     ...pubspec.dependencyOverrides.values.expand(expandDependency),
   ];
 
-  yield* versions
-      .whereType<Version>() // only consider non-null values
+  yield* versions.nonNulls
       .where((v) => _strictRegExp.matchAsPrefix(v.toString()) == null)
       .map((v) => ArchiveIssue(
           'Version value `$v` does not follow strict version pattern.'));

pkg/web_app/lib/src/deferred/http.dart

@@ -18,8 +18,7 @@ String? _getCsrfMetaContent() {
   final values = document.head
       ?.querySelectorAll('meta[name="csrf-token"]')
       .map((e) => e.attributes['content'])
-      .where((e) => e != null)
-      .cast<String>()
+      .nonNulls
       .toList();
   if (values == null || values.isEmpty) {
     return null;

pkg/web_app/lib/src/mobile_nav.dart

@@ -16,7 +16,7 @@ void _setEventForMobileNav() {
   final mask = document.querySelector('.site-header-mask');
   final nav = document.querySelector('.site-header-nav');
 
-  final allElems = [nav, mask].where((e) => e != null).cast<Element>().toList();
+  final allElems = [nav, mask].nonNulls.toList();
 
   hamburger?.onClick.listen((_) {
     // This opacity hack enables smooth initialization, otherwise users would

pkg/web_app/lib/src/search.dart

@@ -145,7 +145,7 @@ String _openSectionParams() {
       .where((e) =>
           e.dataset.containsKey('section-tag') && e.classes.contains('-active'))
       .map((e) => e.dataset['section-tag'])
-      .whereType<String>()
+      .nonNulls
       .join(' ');
 }