Add M3 support for iconbuttons in error state in TextFields (#119925)

* add m3 iconbutton override

* changes

* spring cleaning

* whitespace fix

* sneaky whitespaces

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

@@ -12,6 +12,8 @@ import 'package:flutter/widgets.dart';
 import 'color_scheme.dart';
 import 'colors.dart';
 import 'constants.dart';
+import 'icon_button.dart';
+import 'icon_button_theme.dart';
 import 'input_border.dart';
 import 'material.dart';
 import 'material_state.dart';
@@ -2307,19 +2309,27 @@ class _InputDecoratorState extends State<InputDecorator> with TickerProviderStat
           cursor: SystemMouseCursors.basic,
           child: ConstrainedBox(
             constraints: decoration.prefixIconConstraints ??
-                themeData.visualDensity.effectiveConstraints(
-                  const BoxConstraints(
-                    minWidth: kMinInteractiveDimension,
-                    minHeight: kMinInteractiveDimension,
-                  ),
+              themeData.visualDensity.effectiveConstraints(
+                const BoxConstraints(
+                  minWidth: kMinInteractiveDimension,
+                  minHeight: kMinInteractiveDimension,
                 ),
+              ),
             child: IconTheme.merge(
               data: IconThemeData(
                 color: _getPrefixIconColor(themeData, defaults),
                 size: iconSize,
               ),
-              child: Semantics(
-                child: decoration.prefixIcon,
+              child: IconButtonTheme(
+                data: IconButtonThemeData(
+                style: IconButton.styleFrom(
+                  foregroundColor: _getPrefixIconColor(themeData, defaults),
+                  iconSize: iconSize,
+                  ),
+                ),
+                child: Semantics(
+                  child: decoration.prefixIcon,
+                ),
               ),
             ),
           ),
@@ -2334,24 +2344,32 @@ class _InputDecoratorState extends State<InputDecorator> with TickerProviderStat
           cursor: SystemMouseCursors.basic,
           child: ConstrainedBox(
             constraints: decoration.suffixIconConstraints ??
-                themeData.visualDensity.effectiveConstraints(
-                  const BoxConstraints(
-                    minWidth: kMinInteractiveDimension,
-                    minHeight: kMinInteractiveDimension,
-                  ),
+              themeData.visualDensity.effectiveConstraints(
+                const BoxConstraints(
+                  minWidth: kMinInteractiveDimension,
+                  minHeight: kMinInteractiveDimension,
                 ),
-            child: IconTheme.merge(
-              data: IconThemeData(
-                color: _getSuffixIconColor(themeData, defaults),
-                size: iconSize,
               ),
-              child: Semantics(
-                child: decoration.suffixIcon,
+              child: IconTheme.merge(
+                data: IconThemeData(
+                  color: _getSuffixIconColor(themeData, defaults),
+                  size: iconSize,
+                ),
+                child: IconButtonTheme(
+                  data: IconButtonThemeData(
+                  style: IconButton.styleFrom(
+                    foregroundColor: _getSuffixIconColor(themeData, defaults),
+                    iconSize: iconSize,
+                    ),
+                  ),
+                  child: Semantics(
+                    child: decoration.suffixIcon,
+                  ),
+                ),
               ),
             ),
           ),
-        ),
-      );
+        );
 
     final Widget helperError = _HelperError(
       textAlign: textAlign,

packages/flutter/test/material/input_decorator_test.dart

@@ -148,6 +148,13 @@ double getOpacity(WidgetTester tester, String textValue) {
   return opacityWidget.opacity.value;
 }
 
+TextStyle? getIconStyle(WidgetTester tester, IconData icon) {
+  final RichText iconRichText = tester.widget<RichText>(
+    find.descendant(of: find.byIcon(icon), matching: find.byType(RichText)),
+  );
+  return iconRichText.text.style;
+}
+
 void main() {
   for(final bool useMaterial3 in  <bool>[true, false]){
   testWidgets('InputDecorator input/label text layout', (WidgetTester tester) async {
@@ -1732,6 +1739,33 @@ void main() {
     expect(tester.widget<IconTheme>(find.widgetWithIcon(IconTheme,Icons.close).first).data.color, Colors.red);
   });
 
+  testWidgets('InputDecorator suffixIconColor in M3 error state', (WidgetTester tester) async {
+    final ThemeData theme = ThemeData(
+          useMaterial3: true,
+          iconButtonTheme: const IconButtonThemeData(
+            style: ButtonStyle(
+              foregroundColor: MaterialStatePropertyAll<Color>(Colors.blue),
+            ),
+          ),
+        );
+    await tester.pumpWidget(
+       MaterialApp(
+        theme: theme,
+        home: Material(
+          child: TextField(
+            decoration: InputDecoration(
+              suffixIcon: IconButton(icon: const Icon(Icons.close), onPressed: () {}),
+              errorText: 'error state',
+              filled: true,
+            ),
+          ),
+        ),
+      ),
+    );
+
+    expect(getIconStyle(tester, Icons.close)?.color, theme.colorScheme.error);
+  });
+
   testWidgets('InputDecorator prefix/suffix widgets', (WidgetTester tester) async {
     const Key pKey = Key('p');
     const Key sKey = Key('s');