Add Horizontal Padding to Constrained Chip Label Calculations (#31861)

* Add horizontal padding and properly constrain chip label calculations

* Added regression test for avatar, label and delete icon constraint

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

@@ -2188,29 +2188,40 @@ class _RenderChip extends RenderBox {
     // Now that we know the label height and the width of the icons, we can
     // determine how much to shrink the width constraints for the "real" layout.
     if (constraints.maxWidth.isFinite) {
+      final double maxWidth = math.max(
+        0.0,
+        constraints.maxWidth
+        - iconSizes
+        - theme.labelPadding.horizontal
+        - theme.padding.horizontal,
+      );
       label.layout(
         constraints.copyWith(
           minWidth: 0.0,
-          maxWidth: math.max(
-            0.0,
-            constraints.maxWidth - iconSizes - theme.labelPadding.horizontal,
-          ),
+          maxWidth: maxWidth,
           minHeight: rawSize.height,
           maxHeight: size.height,
         ),
         parentUsesSize: true,
       );
-    } else {
-      label.layout(
-        BoxConstraints(
-          minHeight: rawSize.height,
-          maxHeight: size.height,
-          minWidth: 0.0,
-          maxWidth: size.width,
-        ),
-        parentUsesSize: true,
+
+      final Size updatedSize = _boxSize(label);
+      return Size(
+        updatedSize.width + theme.labelPadding.horizontal,
+        updatedSize.height + theme.labelPadding.vertical,
       );
     }
+
+    label.layout(
+      BoxConstraints(
+        minHeight: rawSize.height,
+        maxHeight: size.height,
+        minWidth: 0.0,
+        maxWidth: size.width,
+      ),
+      parentUsesSize: true,
+    );
+
     return Size(
       rawSize.width + theme.labelPadding.horizontal,
       rawSize.height + theme.labelPadding.vertical,

packages/flutter/test/material/chip_test.dart

@@ -248,6 +248,79 @@ void main() {
     );
   });
 
+  testWidgets(
+      'Chip constrains the avatar, label, and delete icons to the bounds of '
+      'the chip when it exceeds the available space', (WidgetTester tester) async {
+    // Regression test for https://github.com/flutter/flutter/issues/11523
+    Widget chipBuilder (String text, {Widget avatar, VoidCallback onDeleted}) {
+      return MaterialApp(
+        home: Scaffold(
+          body: Container(
+            width: 150,
+            child: Column(
+              children: <Widget>[
+                Chip(
+                  avatar: avatar,
+                  label: Text(text),
+                  onDeleted: onDeleted,
+                ),
+              ]
+            ),
+          ),
+        ),
+      );
+    }
+
+    void chipRectContains(Rect chipRect, Rect rect) {
+      expect(chipRect.contains(rect.topLeft), true);
+      expect(chipRect.contains(rect.topRight), true);
+      expect(chipRect.contains(rect.bottomLeft), true);
+      expect(chipRect.contains(rect.bottomRight), true);
+    }
+
+    Rect chipRect;
+    Rect avatarRect;
+    Rect labelRect;
+    Rect deleteIconRect;
+    const String text = 'Very long text that will be clipped';
+
+    await tester.pumpWidget(chipBuilder(text));
+
+    chipRect = tester.getRect(find.byType(Chip));
+    labelRect = tester.getRect(find.text(text));
+    chipRectContains(chipRect, labelRect);
+
+    await tester.pumpWidget(chipBuilder(
+      text,
+      avatar: const CircleAvatar(child: Text('A')),
+    ));
+    await tester.pumpAndSettle();
+
+    chipRect = tester.getRect(find.byType(Chip));
+    avatarRect = tester.getRect(find.byType(CircleAvatar));
+    chipRectContains(chipRect, avatarRect);
+
+    labelRect = tester.getRect(find.text(text));
+    chipRectContains(chipRect, labelRect);
+
+    await tester.pumpWidget(chipBuilder(
+      text,
+      avatar: const CircleAvatar(child: Text('A')),
+      onDeleted: () {},
+    ));
+    await tester.pumpAndSettle();
+
+    chipRect = tester.getRect(find.byType(Chip));
+    avatarRect = tester.getRect(find.byType(CircleAvatar));
+    chipRectContains(chipRect, avatarRect);
+
+    labelRect = tester.getRect(find.text(text));
+    chipRectContains(chipRect, labelRect);
+
+    deleteIconRect = tester.getRect(find.byIcon(Icons.cancel));
+    chipRectContains(chipRect, deleteIconRect);
+  });
+
   testWidgets('Chip in row works ok', (WidgetTester tester) async {
     const TextStyle style = TextStyle(fontFamily: 'Ahem', fontSize: 10.0);
     await tester.pumpWidget(