[CFE] Expression compilation overwrites types to static types if from "dart:"

jensjoha · Commit Queue · commit c9ebb0e31166 · 2025-11-09T23:33:10.000-08:00
When the VM has an `int` it often represents it as a `_Smi` (which extends `_IntegerImplementation` which implements `int`), but the interface member for e.g. `+` on `_Smi` is `_IntegerImplementation.+` and `_IntegerImplementation` is not special-cased in `isSpecialCasedBinaryOperator` (but `int` and `num` is, so using `int` having the interface member `num.+` makes `isSpecialCasedBinaryOperator` return true if the type is `int` but false if the type is `_Smi`). Not knowing which specialized types the VM could send for more general types that are then specialized in the compiler this CL fixes the issue (linked below) by using the static types of definitions from `dart:`. Fixes #61894 Change-Id: I66cb2d44d5762719b14b51cb139fa0df6b00468f Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/459420 Reviewed-by: Ben Konyi <bkonyi@google.com> Commit-Queue: Jens Johansen <jensj@google.com> Reviewed-by: Johnni Winther <johnniwinther@google.com>
diff --git a/pkg/front_end/lib/src/base/incremental_compiler.dart b/pkg/front_end/lib/src/base/incremental_compiler.dart
@@ -35,6 +35,7 @@ import 'package:kernel/kernel.dart'
         DynamicType,
         Expression,
         ExtensionType,
+        Field,
         FunctionNode,
         InterfaceType,
         Library,
@@ -43,6 +44,7 @@ import 'package:kernel/kernel.dart'
         Name,
         NamedNode,
         Node,
+        Nullability,
         Procedure,
         ProcedureKind,
         Reference,
@@ -51,13 +53,12 @@ import 'package:kernel/kernel.dart'
         Supertype,
         TreeNode,
         TypeParameter,
+        TypeParameterType,
         VariableDeclaration,
         VariableGet,
         VariableSet,
         VisitorDefault,
-        VisitorVoidMixin,
-        TypeParameterType,
-        Field;
+        VisitorVoidMixin;
 import 'package:kernel/kernel.dart' as kernel show Combinator;
 import 'package:kernel/reference_from_index.dart';
 import 'package:kernel/target/changed_structure_notifier.dart'
@@ -1947,6 +1948,22 @@ class IncrementalCompiler implements IncrementalKernelGenerator {
               usedDefinitions[def.key] = substitution.substituteType(
                 def.value.type,
               );
+            } else if (existingType is InterfaceType &&
+                existingType.classNode.enclosingLibrary.importUri.isScheme(
+                  "dart",
+                )) {
+              // The VM tells us about a type from the platform.
+              // We use the static type instead because the compiler for
+              // instance special case int in certain places which is - by the
+              // VM - often described as _Smi.
+              DartType usedType = substitution.substituteType(def.value.type);
+              if (existingType.nullability == Nullability.nonNullable &&
+                  usedType.nullability == Nullability.nullable) {
+                // If a statically nullable type is known to be non-null,
+                // we keep that information though.
+                usedType = usedType.toNonNull();
+              }
+              usedDefinitions[def.key] = usedType;
             }
           }
         }
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_01.expression.yaml.expect b/pkg/front_end/testcases/expression/beyond_dart_semantics_01.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<#lib1::A> list) → dynamic
-  return list.{dart.core::_GrowableList::first}{#lib1::A}{dynamic}.value;
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<#lib1::A> list) → dynamic
+  return list.{dart.core::Iterable::first}{#lib1::A}{dynamic}.value;
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_02.expression.yaml.expect b/pkg/front_end/testcases/expression/beyond_dart_semantics_02.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<#lib1::A> list) → dynamic
-  return list.{dart.core::_GrowableList::first}{#lib1::A}{dynamic}._value;
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<#lib1::A> list) → dynamic
+  return list.{dart.core::Iterable::first}{#lib1::A}{dynamic}._value;
diff --git a/pkg/front_end/testcases/expression/evaluate_const_local_01.expression.yaml.expect b/pkg/front_end/testcases/expression/evaluate_const_local_01.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_OneByteString foo, dart.core::_GrowableList<dart.core::String> list) → dynamic
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::String foo, dart.core::List<dart.core::String> list) → dynamic
   return foo;
diff --git a/pkg/front_end/testcases/expression/evaluate_const_local_02.expression.yaml.expect b/pkg/front_end/testcases/expression/evaluate_const_local_02.expression.yaml.expect
@@ -1,6 +1,6 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<dart.core::String> list, dart.core::_OneByteString input) → dynamic
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<dart.core::String> list, dart.core::String input) → dynamic
   return #C1;
 constants  {
   #C1 = "hello from foo"
diff --git a/pkg/front_end/testcases/expression/extension_with_inner_function_declaration.expression.yaml.expect b/pkg/front_end/testcases/expression/extension_with_inner_function_declaration.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(lowered dart.core::_Smi #this) → dynamic
+method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(lowered dart.core::int #this) → dynamic
   return #this;
diff --git a/pkg/front_end/testcases/expression/extension_with_inner_function_declaration_vm_sending_in_weird_order.expression.yaml.expect b/pkg/front_end/testcases/expression/extension_with_inner_function_declaration_vm_sending_in_weird_order.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_Smi offset, lowered dart.core::_OneByteString #this) → dynamic
-  return offset.{dart.core::_IntegerImplementation::+}(#this.{dart.core::_StringBase::length}{dart.core::int}){(dart.core::num) → dart.core::num};
+method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::int offset, lowered dart.core::String #this) → dynamic
+  return offset.{dart.core::num::+}(#this.{dart.core::String::length}{dart.core::int}){(dart.core::num) → dart.core::int};
diff --git a/pkg/front_end/testcases/expression/extension_with_inner_function_expression.expression.yaml.expect b/pkg/front_end/testcases/expression/extension_with_inner_function_expression.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(lowered dart.core::_Smi #this) → dynamic
+method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(lowered dart.core::int #this) → dynamic
   return #this;
diff --git a/pkg/front_end/testcases/expression/issue_57040_01.expression.yaml.expect b/pkg/front_end/testcases/expression/issue_57040_01.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_OneByteString str) → dynamic
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::String str) → dynamic
   return #lib1::_extension#0|get#isNullOrEmpty(str);
diff --git a/pkg/front_end/testcases/expression/issue_61294_01.expression.yaml.expect b/pkg/front_end/testcases/expression/issue_61294_01.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(lowered dart.core::_OneByteString #this, dart.core::_OneByteString str) → dynamic
+method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(lowered dart.core::String #this, dart.core::String str) → dynamic
   return str;
diff --git a/pkg/front_end/testcases/expression/issue_61294_02.expression.yaml.expect b/pkg/front_end/testcases/expression/issue_61294_02.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(lowered dart.core::_OneByteString #this, dart.core::_OneByteString str) → dynamic
+method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(lowered dart.core::String #this, dart.core::String str) → dynamic
   return str;
diff --git a/pkg/front_end/testcases/expression/issue_61894.expression.yaml b/pkg/front_end/testcases/expression/issue_61894.expression.yaml
@@ -0,0 +1,31 @@
+# Copyright (c) 2025, 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.
+
+# https://github.com/dart-lang/sdk/issues/61894
+
+sources:
+  main.dart: |
+    import "dart:developer";
+
+    void main() {
+      foo(0);
+    }
+
+    void foo(int a) {
+      if (a > 2) return;
+      debugger();
+      foo(a + 1);
+    }
+
+definitions: ["a"]
+definition_types: ["dart:core", "_Smi", "1", "0"]
+type_definitions: []
+type_bounds: []
+type_defaults: []
+method: "foo"
+static: true
+offset: 102
+scriptUri: main.dart
+expression: |
+  foo(a + 1)
diff --git a/pkg/front_end/testcases/expression/issue_61894.expression.yaml.expect b/pkg/front_end/testcases/expression/issue_61894.expression.yaml.expect
@@ -0,0 +1,4 @@
+Errors: {
+}
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::int a) → dynamic
+  return #lib1::foo(a.{dart.core::num::+}(1){(dart.core::num) → dart.core::int});
diff --git a/pkg/front_end/testcases/expression/list_type_arguments_1.expression.yaml b/pkg/front_end/testcases/expression/list_type_arguments_1.expression.yaml
@@ -0,0 +1,46 @@
+# Copyright (c) 2025, 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.
+
+# Copy of (parts of) pkg/vm_service/test/evaluate_type_arguments_test.dart.
+
+sources:
+  main.dart: |
+    import "dart:developer";
+
+    void testFunction2<E extends String>(List<E> x) {
+      debugger();
+      print('x = $x');
+      () {
+        List<E> y = List<E>.from(["hello"]);
+        x.addAll(y);
+        return x.last;
+      }();
+      print('x = $x');
+      () {
+        List<E> y = [];
+        y.addAll(x);
+        return y.last;
+      }();
+      print('x = $x');
+    }
+
+    void main() {
+      testFunction2<String>(<String>['a', 'b', 'c']);
+    }
+
+definitions: ["x"]
+definition_types: ["dart:core", "_GrowableList", "1", "1", "dart:core", "String", "1", "0"]
+type_definitions: ["E"]
+type_bounds: ["dart:core", "String", "1", "0"]
+type_defaults: ["dart:core", "String", "1", "0"]
+method: "testFunction2"
+static: true
+offset: 78
+scriptUri: main.dart
+expression: |
+  () {
+    List<E> y = List<E>.from(["hello"]);
+    x.addAll(y);
+    return x.last;
+  }()
diff --git a/pkg/front_end/testcases/expression/list_type_arguments_1.expression.yaml.expect b/pkg/front_end/testcases/expression/list_type_arguments_1.expression.yaml.expect
@@ -0,0 +1,8 @@
+Errors: {
+}
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr<E extends dart.core::String>(dart.core::List<#lib1::debugExpr::E> x) → dynamic
+  return (() → #lib1::debugExpr::E {
+    dart.core::List<#lib1::debugExpr::E> y = dart.core::List::from<#lib1::debugExpr::E>(dart.core::_GrowableList::_literal1<dynamic>("hello"));
+    x.{dart.core::List::addAll}(y){(dart.core::Iterable<#lib1::debugExpr::E>) → void};
+    return x.{dart.core::Iterable::last}{#lib1::debugExpr::E};
+  })(){() → #lib1::debugExpr::E};
diff --git a/pkg/front_end/testcases/expression/list_type_arguments_2.expression.yaml b/pkg/front_end/testcases/expression/list_type_arguments_2.expression.yaml
@@ -0,0 +1,46 @@
+# Copyright (c) 2025, 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.
+
+# Copy of (parts of) pkg/vm_service/test/evaluate_type_arguments_test.dart.
+
+sources:
+  main.dart: |
+    import "dart:developer";
+
+    void testFunction2<E extends String>(List<E> x) {
+      debugger();
+      print('x = $x');
+      () {
+        List<E> y = List<E>.from(["hello"]);
+        x.addAll(y);
+        return x.last;
+      }();
+      print('x = $x');
+      () {
+        List<E> y = [];
+        y.addAll(x);
+        return y.last;
+      }();
+      print('x = $x');
+    }
+
+    void main() {
+      testFunction2<String>(<String>['a', 'b', 'c']);
+    }
+
+definitions: ["x"]
+definition_types: ["dart:core", "_GrowableList", "1", "1", "dart:core", "String", "1", "0"]
+type_definitions: ["E"]
+type_bounds: ["dart:core", "String", "1", "0"]
+type_defaults: ["dart:core", "String", "1", "0"]
+method: "testFunction2"
+static: true
+offset: 78
+scriptUri: main.dart
+expression: |
+  () {
+    List<E> y = [];
+    y.addAll(x);
+    return y.last;
+  }()
diff --git a/pkg/front_end/testcases/expression/list_type_arguments_2.expression.yaml.expect b/pkg/front_end/testcases/expression/list_type_arguments_2.expression.yaml.expect
@@ -0,0 +1,8 @@
+Errors: {
+}
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr<E extends dart.core::String>(dart.core::List<#lib1::debugExpr::E> x) → dynamic
+  return (() → #lib1::debugExpr::E {
+    dart.core::List<#lib1::debugExpr::E> y = dart.core::_GrowableList::•<#lib1::debugExpr::E>(0);
+    y.{dart.core::List::addAll}(x){(dart.core::Iterable<#lib1::debugExpr::E>) → void};
+    return y.{dart.core::Iterable::last}{#lib1::debugExpr::E};
+  })(){() → #lib1::debugExpr::E};
diff --git a/pkg/vm_service/test/evaluate_type_arguments_test.dart b/pkg/vm_service/test/evaluate_type_arguments_test.dart
@@ -5,7 +5,6 @@
 import 'dart:collection';
 import 'dart:developer';
 
-import 'package:test/test.dart';
 import 'package:vm_service/vm_service.dart';
 
 import 'common/service_test_common.dart';
@@ -17,9 +16,9 @@ import 'common/test_helper.dart';
 //
 // dart pkg/vm_service/test/update_line_numbers.dart pkg/vm_service/test/evaluate_type_arguments_test.dart
 //
-const LINE_A = 39;
-const LINE_B = 44;
-const LINE_C = 50;
+const LINE_A = 38;
+const LINE_B = 43;
+const LINE_C = 49;
 // AUTOGENERATED END
 
 class A {}
@@ -87,20 +86,16 @@ final tests = <IsolateTest>[
         return y.last;
       }()
       ''';
-      // Can't add List<String> to List<E extends String> directly.
-      try {
-        await service.evaluateInFrame(isolateId, 0, expression);
-        fail("Can't add List<String> to List<E extends String> directly.");
-      } on RPCError catch (e) {
-        expect(e.code, RPCErrorKind.kExpressionCompilationError.code);
-        expect(
-          e.details,
-          contains(
-            "The argument type '_GrowableList<String>' can't be assigned "
-            "to the parameter type 'Iterable<E>'",
-          ),
-        );
-      }
+      // We wouldnt be able to add List<String> to List<E extends String>,
+      // but the CFE now uses static types for "dart:" definitions, making this
+      // adding List<E extends String> to List<E extends String>.
+      await evaluateInFrameAndExpect(
+        service,
+        isolateId,
+        expression,
+        'hello',
+        kind: InstanceKind.kString,
+      );
     }
     {
       // Can add List<String> to List<E extends String> via cast.

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`	`1`	`Errors: {`
`2`	`2`	`}`
`3`		`-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<#lib1::A> list) → dynamic`
`4`		`- return list.{dart.core::_GrowableList::first}{#lib1::A}{dynamic}.value;`
	`3`	`+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<#lib1::A> list) → dynamic`
	`4`	`+ return list.{dart.core::Iterable::first}{#lib1::A}{dynamic}.value;`
Original file line number	Diff line number	Diff line change
`@@ -1,6 +1,6 @@`
`1`	`1`	`Errors: {`
`2`	`2`	`}`
`3`		`-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<dart.core::String> list, dart.core::_OneByteString input) → dynamic`
	`3`	`+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<dart.core::String> list, dart.core::String input) → dynamic`
`4`	`4`	`return #C1;`
`5`	`5`	`constants {`
`6`	`6`	`#C1 = "hello from foo"`
Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`	`1`	`Errors: {`
`2`	`2`	`}`
`3`		`-method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(lowered dart.core::_Smi #this) → dynamic`
	`3`	`+method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(lowered dart.core::int #this) → dynamic`
`4`	`4`	`return #this;`