Remove unnecessary null checks in flutter/material (#119022)

* dart fix --apply

* manual fixes

Author: goderbauer

packages/flutter/lib/src/material/about.dart

@@ -184,8 +184,6 @@ void showAboutDialog({
   RouteSettings? routeSettings,
   Offset? anchorPoint,
 }) {
-  assert(context != null);
-  assert(useRootNavigator != null);
   showDialog<void>(
     context: context,
     useRootNavigator: useRootNavigator,
@@ -230,8 +228,6 @@ void showLicensePage({
   String? applicationLegalese,
   bool useRootNavigator = false,
 }) {
-  assert(context != null);
-  assert(useRootNavigator != null);
   Navigator.of(context, rootNavigator: useRootNavigator).push(MaterialPageRoute<void>(
     builder: (BuildContext context) => LicensePage(
       applicationName: applicationName,
@@ -486,8 +482,7 @@ class _AboutProgram extends StatelessWidget {
     required this.version,
     this.icon,
     this.legalese,
-  })  : assert(name != null),
-        assert(version != null);
+  });
 
   final String name;
   final String version;
@@ -542,8 +537,7 @@ class _PackagesView extends StatefulWidget {
     required this.about,
     required this.isLateral,
     required this.selectedId,
-  })  : assert(about != null),
-        assert(isLateral != null);
+  });
 
   final Widget about;
   final bool isLateral;
@@ -1044,14 +1038,11 @@ class _MasterDetailFlow extends StatefulWidget {
   const _MasterDetailFlow({
     required this.detailPageBuilder,
     required this.masterViewBuilder,
-    this.automaticallyImplyLeading = true,
+    this.automaticallyImplyLeading = true, // ignore: unused_element
     this.detailPageFABlessGutterWidth,
-    this.displayMode = _LayoutMode.auto,
+    this.displayMode = _LayoutMode.auto, // ignore: unused_element
     this.title,
-  })  : assert(masterViewBuilder != null),
-        assert(automaticallyImplyLeading != null),
-        assert(detailPageBuilder != null),
-        assert(displayMode != null);
+  });
 
   /// Builder for the master view for lateral navigation.
   ///
@@ -1312,8 +1303,7 @@ class _MasterDetailScaffold extends StatefulWidget {
     this.title,
     required this.automaticallyImplyLeading,
     this.detailPageFABlessGutterWidth,
-  })  : assert(detailPageBuilder != null),
-        assert(masterViewBuilder != null);
+  });
 
   final _MasterViewBuilder masterViewBuilder;
 
@@ -1462,8 +1452,7 @@ class _DetailView extends StatelessWidget {
   const _DetailView({
     required _DetailPageBuilder builder,
     Object? arguments,
-  })  : assert(builder != null),
-        _builder = builder,
+  })  : _builder = builder,
         _arguments = arguments;
 
   final _DetailPageBuilder _builder;

packages/flutter/lib/src/material/action_chip.dart

@@ -86,10 +86,7 @@ class ActionChip extends StatelessWidget implements ChipAttributes, TappableChip
     this.shadowColor,
     this.surfaceTintColor,
     this.iconTheme,
-  }) : assert(label != null),
-       assert(clipBehavior != null),
-       assert(autofocus != null),
-       assert(pressElevation == null || pressElevation >= 0.0),
+  }) : assert(pressElevation == null || pressElevation >= 0.0),
        assert(elevation == null || elevation >= 0.0);
 
   @override

packages/flutter/lib/src/material/animated_icons/animated_icons.dart

@@ -39,8 +39,7 @@ class AnimatedIcon extends StatelessWidget {
     this.size,
     this.semanticLabel,
     this.textDirection,
-  }) : assert(progress != null),
-       assert(icon != null);
+  });
 
   /// The animation progress for the animated icon.
   ///

packages/flutter/lib/src/material/app.dart

@@ -242,16 +242,7 @@ class MaterialApp extends StatefulWidget {
     this.restorationScopeId,
     this.scrollBehavior,
     this.useInheritedMediaQuery = false,
-  }) : assert(routes != null),
-       assert(navigatorObservers != null),
-       assert(title != null),
-       assert(debugShowMaterialGrid != null),
-       assert(showPerformanceOverlay != null),
-       assert(checkerboardRasterCacheImages != null),
-       assert(checkerboardOffscreenLayers != null),
-       assert(showSemanticsDebugger != null),
-       assert(debugShowCheckedModeBanner != null),
-       routeInformationProvider = null,
+  }) : routeInformationProvider = null,
        routeInformationParser = null,
        routerDelegate = null,
        backButtonDispatcher = null,
@@ -296,13 +287,6 @@ class MaterialApp extends StatefulWidget {
     this.scrollBehavior,
     this.useInheritedMediaQuery = false,
   }) : assert(routerDelegate != null || routerConfig != null),
-       assert(title != null),
-       assert(debugShowMaterialGrid != null),
-       assert(showPerformanceOverlay != null),
-       assert(checkerboardRasterCacheImages != null),
-       assert(checkerboardOffscreenLayers != null),
-       assert(showSemanticsDebugger != null),
-       assert(debugShowCheckedModeBanner != null),
        navigatorObservers = null,
        navigatorKey = null,
        onGenerateRoute = null,

packages/flutter/lib/src/material/app_bar.dart

@@ -223,12 +223,7 @@ class AppBar extends StatefulWidget implements PreferredSizeWidget {
     this.titleTextStyle,
     this.systemOverlayStyle,
     this.forceMaterialTransparency = false,
-  }) : assert(automaticallyImplyLeading != null),
-       assert(elevation == null || elevation >= 0.0),
-       assert(notificationPredicate != null),
-       assert(primary != null),
-       assert(toolbarOpacity != null),
-       assert(bottomOpacity != null),
+  }) : assert(elevation == null || elevation >= 0.0),
        preferredSize = _PreferredAppBarSize(toolbarHeight, bottom?.preferredSize.height);
 
   /// Used by [Scaffold] to compute its [AppBar]'s overall height. The returned value is
@@ -809,7 +804,6 @@ class AppBar extends StatefulWidget implements PreferredSizeWidget {
 
   bool _getEffectiveCenterTitle(ThemeData theme) {
     bool platformCenter() {
-      assert(theme.platform != null);
       switch (theme.platform) {
         case TargetPlatform.android:
         case TargetPlatform.fuchsia:
@@ -1323,10 +1317,6 @@ class _SliverAppBarDelegate extends SliverPersistentHeaderDelegate {
     required this.systemOverlayStyle,
     required this.forceMaterialTransparency,
   }) : assert(primary || topPadding == 0.0),
-       assert(
-         !floating || (snapConfiguration == null && showOnScreenConfiguration == null) || vsync != null,
-         'vsync cannot be null when snapConfiguration or showOnScreenConfiguration is not null, and floating is true',
-       ),
        _bottomHeight = bottom?.preferredSize.height ?? 0.0;
 
   final Widget? leading;
@@ -1627,15 +1617,7 @@ class SliverAppBar extends StatefulWidget {
     this.titleTextStyle,
     this.systemOverlayStyle,
     this.forceMaterialTransparency = false,
-  }) : assert(automaticallyImplyLeading != null),
-       assert(forceElevated != null),
-       assert(primary != null),
-       assert(floating != null),
-       assert(pinned != null),
-       assert(snap != null),
-       assert(stretch != null),
-       assert(toolbarHeight != null),
-       assert(floating || !snap, 'The "snap" argument only makes sense for floating app bars.'),
+  }) : assert(floating || !snap, 'The "snap" argument only makes sense for floating app bars.'),
        assert(stretchTriggerOffset > 0.0),
        assert(collapsedHeight == null || collapsedHeight >= toolbarHeight, 'The "collapsedHeight" argument has to be larger than or equal to [toolbarHeight].');
 
@@ -2241,7 +2223,7 @@ class _SliverAppBarState extends State<SliverAppBar> with TickerProviderStateMix
 // center it within its (NavigationToolbar) parent, and allow the
 // parent to constrain the title's actual height.
 class _AppBarTitleBox extends SingleChildRenderObjectWidget {
-  const _AppBarTitleBox({ required Widget super.child }) : assert(child != null);
+  const _AppBarTitleBox({ required Widget super.child });
 
   @override
   _RenderAppBarTitleBox createRenderObject(BuildContext context) {
@@ -2332,7 +2314,6 @@ class _ScrollUnderFlexibleSpace extends StatelessWidget {
     late final bool centerTitle;
     {
       bool platformCenter() {
-        assert(theme.platform != null);
         switch (theme.platform) {
           case TargetPlatform.android:
           case TargetPlatform.fuchsia:

packages/flutter/lib/src/material/app_bar_theme.dart

@@ -306,7 +306,6 @@ class AppBarTheme with Diagnosticable {
   ///
   /// {@macro dart.ui.shadow.lerp}
   static AppBarTheme lerp(AppBarTheme? a, AppBarTheme? b, double t) {
-    assert(t != null);
     return AppBarTheme(
       brightness: t < 0.5 ? a?.brightness : b?.brightness,
       backgroundColor: Color.lerp(a?.backgroundColor, b?.backgroundColor, t),

packages/flutter/lib/src/material/autocomplete.dart

@@ -43,8 +43,7 @@ class Autocomplete<T extends Object> extends StatelessWidget {
     this.optionsMaxHeight = 200.0,
     this.optionsViewBuilder,
     this.initialValue,
-  }) : assert(displayStringForOption != null),
-       assert(optionsBuilder != null);
+  });
 
   /// {@macro flutter.widgets.RawAutocomplete.displayStringForOption}
   final AutocompleteOptionToString<T> displayStringForOption;

packages/flutter/lib/src/material/badge_theme.dart

@@ -153,7 +153,7 @@ class BadgeTheme extends InheritedTheme {
     super.key,
     required this.data,
     required super.child,
-  }) : assert(data != null);
+  });
 
   /// Specifies the default color and size overrides for descendant [Badge] widgets.
   final BadgeThemeData data;

packages/flutter/lib/src/material/banner.dart

@@ -111,10 +111,7 @@ class MaterialBanner extends StatefulWidget {
     this.overflowAlignment = OverflowBarAlignment.end,
     this.animation,
     this.onVisible,
-  }) : assert(elevation == null || elevation >= 0.0),
-       assert(content != null),
-       assert(actions != null),
-       assert(forceActionsBelow != null);
+  }) : assert(elevation == null || elevation >= 0.0);
 
   /// The content of the [MaterialBanner].
   ///

packages/flutter/lib/src/material/banner_theme.dart

@@ -101,7 +101,6 @@ class MaterialBannerThemeData with Diagnosticable {
   ///
   /// {@macro dart.ui.shadow.lerp}
   static MaterialBannerThemeData lerp(MaterialBannerThemeData? a, MaterialBannerThemeData? b, double t) {
-    assert(t != null);
     return MaterialBannerThemeData(
       backgroundColor: Color.lerp(a?.backgroundColor, b?.backgroundColor, t),
       surfaceTintColor: Color.lerp(a?.surfaceTintColor, b?.surfaceTintColor, t),