[cfe] Skip addSuperParameterDefaultValueCloners when the constructor has no super initializing formals

Initializers are created for outlines for const constructors and for constructors with super initializing formals. This led the addSuperParameterDefaultValueCloners method to process the initializers even when the constructor has no super initializing formals; crashing in the case of const redirecting generative constructors. The addSuperParameterDefaultValueCloners method now stops early if the constructor has no super initializing formals.

Change-Id: I2d640b20ac3fb281705b61362157e1fd09eed3f8
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/490081
Reviewed-by: Chloe Stefantsova <cstefantsova@google.com>
Commit-Queue: Johnni Winther <johnniwinther@google.com>

Author: johnniwinther

pkg/front_end/lib/src/fragment/constructor/declaration.dart

@@ -475,6 +475,7 @@ mixin _ConstructorDeclarationMixin
     } else if (lastInitializer is InternalSuperInitializer) {
       superTarget = lastInitializer.target;
     } else if (lastInitializer is InvalidInitializer &&
+        // Coverage-ignore(suite): Not run.
         lastInitializer.isSuperInitializer) {
       // Erroneous super initializer.
       return null;
@@ -529,6 +530,8 @@ mixin _ConstructorDeclarationMixin
     DeclarationBuilder declarationBuilder,
     List<DelayedDefaultValueCloner> delayedDefaultValueCloners,
   ) {
+    if (!_hasSuperInitializingFormals) return;
+
     if (_beginInitializers != null && initializers.isNotEmpty) {
       // If the initializers aren't built yet, we can't compute the super
       // target. The synthetic initializers should be excluded, since they can

pkg/front_end/testcases/general/const_redirecting.dart

@@ -0,0 +1,13 @@
+// Copyright (c) 2026, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+class A {
+  const A.named();
+}
+
+class B extends A {
+  const B() : super.named();
+
+  const B.named() : this();
+}

pkg/front_end/testcases/general/const_redirecting.dart.strong.expect

@@ -0,0 +1,17 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor named() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends self::A /*hasConstConstructor*/  {
+  const constructor •() → self::B
+    : super self::A::named()
+    ;
+  const constructor named() → self::B
+    : this self::B::•()
+    ;
+}

pkg/front_end/testcases/general/const_redirecting.dart.strong.modular.expect

@@ -0,0 +1,17 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor named() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends self::A /*hasConstConstructor*/  {
+  const constructor •() → self::B
+    : super self::A::named()
+    ;
+  const constructor named() → self::B
+    : this self::B::•()
+    ;
+}

pkg/front_end/testcases/general/const_redirecting.dart.strong.outline.expect

@@ -0,0 +1,17 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor named() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends self::A /*hasConstConstructor*/  {
+  const constructor •() → self::B
+    : super self::A::named()
+    ;
+  const constructor named() → self::B
+    : this self::B::•()
+    ;
+}

pkg/front_end/testcases/general/const_redirecting.dart.strong.transformed.expect

@@ -0,0 +1,17 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor named() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends self::A /*hasConstConstructor*/  {
+  const constructor •() → self::B
+    : super self::A::named()
+    ;
+  const constructor named() → self::B
+    : this self::B::•()
+    ;
+}

pkg/front_end/testcases/general/const_redirecting.dart.textual_outline.expect

@@ -0,0 +1,8 @@
+class A {
+  const A.named();
+}
+
+class B extends A {
+  const B() : super.named();
+  const B.named() : this();
+}

pkg/front_end/testcases/general/const_redirecting.dart.textual_outline_modelled.expect

@@ -0,0 +1,8 @@
+class A {
+  const A.named();
+}
+
+class B extends A {
+  const B() : super.named();
+  const B.named() : this();
+}