From 92e2915b51d91c934398506b7eb1c4812e4221a8 Mon Sep 17 00:00:00 2001
From: Paul Berry <paulberry@google.com>
Date: Fri, 6 Sep 2024 15:24:36 -0700
Subject: [PATCH] [multiple] Avoid new `unreachable_switch_default` warning.
 (flutter/engine#54996)

The Dart analyzer will soon be changed so that if the `default` clause
of a `switch` statement is determined to be unreachable by the
exhaustiveness checker, a new warning of type
`unreachable_switch_default` will be issued. This parallels the behavior
of the existing `unreachable_switch_case` warning, which is issued
whenever a `case` clause of a `switch` statement is determined to be
unreachable.

Before adding the new warning to the analyzer, code in the engine needs
to first be updated to eliminate these unreachable `default` clauses, so
that the warning won't cause builds to break.

For more information, see
https://github.com/dart-lang/sdk/issues/54575.
---
 .../lib/web_ui/lib/src/engine/canvaskit/color_filter.dart       | 2 --
 .../lib/web_ui/lib/src/engine/canvaskit/embedded_views.dart     | 2 --
 .../flutter/lib/web_ui/lib/src/engine/html/bitmap_canvas.dart   | 2 --
 .../flutter/lib/web_ui/lib/src/engine/html/shaders/shader.dart  | 2 --
 .../src/flutter/lib/web_ui/lib/src/engine/text/paragraph.dart   | 2 --
 .../web_ui/lib/src/engine/text_editing/text_capitalization.dart | 1 -
 6 files changed, 11 deletions(-)

diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/color_filter.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/color_filter.dart
index dea9b30130..71c4123b45 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/color_filter.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/color_filter.dart
@@ -266,7 +266,5 @@ CkColorFilter? createCkColorFilter(EngineColorFilter colorFilter) {
         return const CkLinearToSrgbGammaColorFilter();
       case ColorFilterType.srgbToLinearGamma:
         return const CkSrgbToLinearGammaColorFilter();
-      default:
-        throw StateError('Unknown mode $colorFilter.type for ColorFilter.');
     }
 }
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/embedded_views.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/embedded_views.dart
index a2d7ab4bd8..a99216b763 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/embedded_views.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/canvaskit/embedded_views.dart
@@ -844,8 +844,6 @@ class Mutator {
         return matrix == typedOther.matrix;
       case MutatorType.opacity:
         return alpha == typedOther.alpha;
-      default:
-        return false;
     }
   }
 
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/html/bitmap_canvas.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/html/bitmap_canvas.dart
index 0dcd004bd5..5d21eed1cf 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/html/bitmap_canvas.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/html/bitmap_canvas.dart
@@ -1337,7 +1337,6 @@ String? stringForStrokeCap(ui.StrokeCap? strokeCap) {
     case ui.StrokeCap.round:
       return 'round';
     case ui.StrokeCap.square:
-    default:
       return 'square';
   }
 }
@@ -1349,7 +1348,6 @@ String stringForStrokeJoin(ui.StrokeJoin strokeJoin) {
     case ui.StrokeJoin.bevel:
       return 'bevel';
     case ui.StrokeJoin.miter:
-    default:
       return 'miter';
   }
 }
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/html/shaders/shader.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/html/shaders/shader.dart
index 826d3cace3..126c14770d 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/html/shaders/shader.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/html/shaders/shader.dart
@@ -914,7 +914,5 @@ EngineHtmlColorFilter? createHtmlColorFilter(EngineColorFilter? colorFilter) {
         throw UnimplementedError('ColorFilter.linearToSrgbGamma not implemented for HTML renderer');
       case ColorFilterType.srgbToLinearGamma:
         throw UnimplementedError('ColorFilter.srgbToLinearGamma not implemented for HTML renderer.');
-      default:
-        throw StateError('Unknown mode $colorFilter.type for ColorFilter.');
     }
 }
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/text/paragraph.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/text/paragraph.dart
index a042c67b72..dbb88918dd 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/text/paragraph.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/text/paragraph.dart
@@ -1118,8 +1118,6 @@ String? _decorationStyleToCssString(ui.TextDecorationStyle decorationStyle) {
       return 'solid';
     case ui.TextDecorationStyle.wavy:
       return 'wavy';
-    default:
-      return null;
   }
 }
 
diff --git a/engine/src/flutter/lib/web_ui/lib/src/engine/text_editing/text_capitalization.dart b/engine/src/flutter/lib/web_ui/lib/src/engine/text_editing/text_capitalization.dart
index 8a81829c3c..b230fcfaa4 100644
--- a/engine/src/flutter/lib/web_ui/lib/src/engine/text_editing/text_capitalization.dart
+++ b/engine/src/flutter/lib/web_ui/lib/src/engine/text_editing/text_capitalization.dart
@@ -75,7 +75,6 @@ class TextCapitalizationConfig {
       case TextCapitalization.sentences:
         autocapitalize = 'sentences';
       case TextCapitalization.none:
-      default:
         autocapitalize = 'off';
     }
     if (domInstanceOfString(domElement, 'HTMLInputElement')) {