[js_interop] Use stub for dart2js only when method has annotations

In order to support dart2js pragma annotations on external js_interop
methods, add the ability to generate stubs for getters, setters and
methods. Create stubs for dart2js only when the method has annotations.
Methods can only be handled by stubs when there are a fixed number of
positional arguments,

Move from using a `builder` to using a slightly more general
'treatement' that can also replace the Procedure's function body.

Issue: #60746
Change-Id: I7482f09d430448001d712dd4645d23f78910920d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/429203
Reviewed-by: Srujan Gaddam <[email protected]>
Commit-Queue: Stephen Adams <[email protected]>
Reviewed-by: Chloe Stefantsova <[email protected]>

Author: rakudrama

pkg/_js_interop_checks/lib/src/transformations/js_util_optimizer.dart

@@ -44,6 +44,8 @@ extension type B._(A a) {
   external static B get staticProperty;
 
   external static void set staticProperty(B b);
+
+  external B methodWithOptionalArgument([B? b]);
 }
 
 void method(A a) {
@@ -63,4 +65,6 @@ void method(A a) {
   b1 = B.staticGetter;
   B.staticSetter = b2;
   B.staticProperty = B.staticProperty;
-}
+  b2 = b1.methodWithOptionalArgument(b2);
+  b1 = b2.methodWithOptionalArgument();
+}

pkg/front_end/testcases/dart2js/extension_types/external.dart

@@ -37,6 +37,8 @@ extension type B(self::A a) {
   static set staticSetter = set self::B|staticSetter;
   static get staticProperty = get self::B|staticProperty;
   static set staticProperty = set self::B|staticProperty;
+  method methodWithOptionalArgument = self::B|methodWithOptionalArgument;
+  method tearoff methodWithOptionalArgument = self::B|get#methodWithOptionalArgument;
   constructor _ = self::B|constructor#_;
   constructor tearoff _ = self::B|constructor#_#_#tearOff;
   constructor • = self::B|constructor#;
@@ -76,6 +78,9 @@ external static extension-type-member get B|staticGetter() → self::B% /* erasu
 external static extension-type-member set B|staticSetter(self::B% /* erasure=self::A, declared=! */ b) → void;
 external static extension-type-member get B|staticProperty() → self::B% /* erasure=self::A, declared=! */;
 external static extension-type-member set B|staticProperty(self::B% /* erasure=self::A, declared=! */ b) → void;
+external static extension-type-member method B|methodWithOptionalArgument(lowered final self::B% /* erasure=self::A, declared=! */ #this, [self::B? /* erasure=self::A? */ b = #C1]) → self::B% /* erasure=self::A, declared=! */;
+static extension-type-member method B|get#methodWithOptionalArgument(lowered final self::B% /* erasure=self::A, declared=! */ #this) → ([self::B? /* erasure=self::A? */]) → self::B% /* erasure=self::A, declared=! */
+  return ([self::B? /* erasure=self::A? */ b = #C1]) → self::B% /* erasure=self::A, declared=! */ => self::B|methodWithOptionalArgument(#this, b);
 static method method(self::A a) → void {
   self::B% /* erasure=self::A, declared=! */ b1 = self::B|constructor#(a);
   self::B% /* erasure=self::A, declared=! */ b2 = self::B|constructor#named(0);
@@ -93,6 +98,8 @@ static method method(self::A a) → void {
   b1 = self::B|staticGetter;
   self::B|staticSetter = b2;
   self::B|staticProperty = self::B|staticProperty;
+  b2 = self::B|methodWithOptionalArgument(b1, b2);
+  b1 = self::B|methodWithOptionalArgument(b2);
 }
 
 constants  {

pkg/front_end/testcases/dart2js/extension_types/external.dart.strong.expect

@@ -37,6 +37,8 @@ extension type B(self::A a) {
   static set staticSetter = set self::B|staticSetter;
   static get staticProperty = get self::B|staticProperty;
   static set staticProperty = set self::B|staticProperty;
+  method methodWithOptionalArgument = self::B|methodWithOptionalArgument;
+  method tearoff methodWithOptionalArgument = self::B|get#methodWithOptionalArgument;
   constructor _ = self::B|constructor#_;
   constructor tearoff _ = self::B|constructor#_#_#tearOff;
   constructor • = self::B|constructor#;
@@ -76,6 +78,9 @@ external static extension-type-member get B|staticGetter() → self::B% /* erasu
 external static extension-type-member set B|staticSetter(self::B% /* erasure=self::A, declared=! */ b) → void;
 external static extension-type-member get B|staticProperty() → self::B% /* erasure=self::A, declared=! */;
 external static extension-type-member set B|staticProperty(self::B% /* erasure=self::A, declared=! */ b) → void;
+external static extension-type-member method B|methodWithOptionalArgument(lowered final self::B% /* erasure=self::A, declared=! */ #this, [self::B? /* erasure=self::A? */ b = #C1]) → self::B% /* erasure=self::A, declared=! */;
+static extension-type-member method B|get#methodWithOptionalArgument(lowered final self::B% /* erasure=self::A, declared=! */ #this) → ([self::B? /* erasure=self::A? */]) → self::B% /* erasure=self::A, declared=! */
+  return ([self::B? /* erasure=self::A? */ b = #C1]) → self::B% /* erasure=self::A, declared=! */ => self::B|methodWithOptionalArgument(#this, b);
 static method method(self::A a) → void {
   self::B% /* erasure=self::A, declared=! */ b1 = self::B|constructor#(a);
   self::B% /* erasure=self::A, declared=! */ b2 = self::B|constructor#named(0);
@@ -93,6 +98,8 @@ static method method(self::A a) → void {
   b1 = self::B|staticGetter;
   self::B|staticSetter = b2;
   self::B|staticProperty = self::B|staticProperty;
+  b2 = self::B|methodWithOptionalArgument(b1, b2);
+  b1 = self::B|methodWithOptionalArgument(b2);
 }
 
 constants  {

pkg/front_end/testcases/dart2js/extension_types/external.dart.strong.modular.expect

@@ -36,6 +36,8 @@ extension type B(self::A a) {
   static set staticSetter = set self::B|staticSetter;
   static get staticProperty = get self::B|staticProperty;
   static set staticProperty = set self::B|staticProperty;
+  method methodWithOptionalArgument = self::B|methodWithOptionalArgument;
+  method tearoff methodWithOptionalArgument = self::B|get#methodWithOptionalArgument;
   constructor _ = self::B|constructor#_;
   constructor tearoff _ = self::B|constructor#_#_#tearOff;
   constructor • = self::B|constructor#;
@@ -73,6 +75,9 @@ external static extension-type-member get B|staticGetter() → self::B% /* erasu
 external static extension-type-member set B|staticSetter(self::B% /* erasure=self::A, declared=! */ b) → void;
 external static extension-type-member get B|staticProperty() → self::B% /* erasure=self::A, declared=! */;
 external static extension-type-member set B|staticProperty(self::B% /* erasure=self::A, declared=! */ b) → void;
+external static extension-type-member method B|methodWithOptionalArgument(lowered final self::B% /* erasure=self::A, declared=! */ #this, [self::B? /* erasure=self::A? */ b]) → self::B% /* erasure=self::A, declared=! */;
+static extension-type-member method B|get#methodWithOptionalArgument(lowered final self::B% /* erasure=self::A, declared=! */ #this) → ([self::B? /* erasure=self::A? */]) → self::B% /* erasure=self::A, declared=! */
+  return ([self::B? /* erasure=self::A? */ b]) → self::B% /* erasure=self::A, declared=! */ => self::B|methodWithOptionalArgument(#this, b);
 static method method(self::A a) → void
   ;
 
@@ -82,4 +87,4 @@ Evaluated: ConstructorInvocation @ org-dartlang-testcase:///external.dart:5:2 ->
 Evaluated: ConstructorInvocation @ org-dartlang-testcase:///external.dart:10:2 -> InstanceConstant(const JS{JS.name: null})
 Evaluated: StaticGet @ org-dartlang-testcase:///external.dart:11:2 -> InstanceConstant(const _StaticInterop{})
 Evaluated: ConstructorInvocation @ org-dartlang-testcase:///external.dart:14:2 -> InstanceConstant(const JS{JS.name: null})
-Extra constant evaluation: evaluated: 18, effectively constant: 4
+Extra constant evaluation: evaluated: 22, effectively constant: 4

pkg/front_end/testcases/dart2js/extension_types/external.dart.strong.outline.expect

@@ -39,6 +39,8 @@ extension type B(self::A a) {
   static set staticSetter = set self::B|staticSetter;
   static get staticProperty = get self::B|staticProperty;
   static set staticProperty = set self::B|staticProperty;
+  method methodWithOptionalArgument = self::B|methodWithOptionalArgument;
+  method tearoff methodWithOptionalArgument = self::B|get#methodWithOptionalArgument;
   constructor _ = self::B|constructor#_;
   constructor tearoff _ = self::B|constructor#_#_#tearOff;
   constructor • = self::B|constructor#;
@@ -70,17 +72,17 @@ external static extension-type-member method B|get#getter(lowered final self::B%
 external static extension-type-member method B|set#setter(lowered final self::B% /* erasure=self::A, declared=! */ #this, self::B% /* erasure=self::A, declared=! */ b) → void;
 external static extension-type-member method B|get#property(lowered final self::B% /* erasure=self::A, declared=! */ #this) → self::B% /* erasure=self::A, declared=! */;
 external static extension-type-member method B|set#property(lowered final self::B% /* erasure=self::A, declared=! */ #this, self::B% /* erasure=self::A, declared=! */ b) → void;
-static extension-type-member get B|staticField() → self::A
-  return js_2::_getPropertyTrustType<dynamic>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticField") as{TypeError,ForDynamic} self::A;
+external static extension-type-member get B|staticField() → self::A;
 external static extension-type-member set B|staticField(synthesized self::A #externalFieldValue) → void;
 external static extension-type-member method B|staticMethod() → self::A;
 external static extension-type-member method B|staticGenericMethod<T extends self::B% /* erasure=self::A, declared=! */>(self::B|staticGenericMethod::T% t) → self::B|staticGenericMethod::T%;
-static extension-type-member get B|staticGetter() → self::B% /* erasure=self::A, declared=! */
-  return js_2::_getPropertyTrustType<dynamic>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticGetter") as{TypeError,ForDynamic} self::B% /* erasure=self::A, declared=! */;
+external static extension-type-member get B|staticGetter() → self::B% /* erasure=self::A, declared=! */;
 external static extension-type-member set B|staticSetter(self::B% /* erasure=self::A, declared=! */ b) → void;
-static extension-type-member get B|staticProperty() → self::B% /* erasure=self::A, declared=! */
-  return js_2::_getPropertyTrustType<dynamic>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticProperty") as{TypeError,ForDynamic} self::B% /* erasure=self::A, declared=! */;
+external static extension-type-member get B|staticProperty() → self::B% /* erasure=self::A, declared=! */;
 external static extension-type-member set B|staticProperty(self::B% /* erasure=self::A, declared=! */ b) → void;
+external static extension-type-member method B|methodWithOptionalArgument(lowered final self::B% /* erasure=self::A, declared=! */ #this, [self::B? /* erasure=self::A? */ b = #C1]) → self::B% /* erasure=self::A, declared=! */;
+static extension-type-member method B|get#methodWithOptionalArgument(lowered final self::B% /* erasure=self::A, declared=! */ #this) → ([self::B? /* erasure=self::A? */]) → self::B% /* erasure=self::A, declared=! */
+  return ([self::B? /* erasure=self::A? */ b = #C1]) → self::B% /* erasure=self::A, declared=! */ => js_2::_callMethodUnchecked1<self::B% /* erasure=self::A, declared=! */>(#this, "methodWithOptionalArgument", b);
 static method method(self::A a) → void {
   self::B% /* erasure=self::A, declared=! */ b1 = js_2::_callConstructorUnchecked1<self::B% /* erasure=self::A, declared=! */>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), a);
   self::B% /* erasure=self::A, declared=! */ b2 = js_2::_callConstructorUnchecked1<self::B% /* erasure=self::A, declared=! */>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), 0);
@@ -91,13 +93,15 @@ static method method(self::A a) → void {
   b1 = js_2::getProperty<self::B% /* erasure=self::A, declared=! */>(b2, "getter");
   js_2::_setPropertyUnchecked<self::B% /* erasure=self::A, declared=! */>(b1, "setter", b2);
   js_2::_setPropertyUnchecked<self::B% /* erasure=self::A, declared=! */>(b1, "property", js_2::getProperty<self::B% /* erasure=self::A, declared=! */>(b2, "property"));
-  a = self::B|staticField;
+  a = js_2::getProperty<self::A>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticField");
   js_2::_setPropertyUnchecked<self::A>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticField", a);
   a = js_2::_callMethodUnchecked0<self::A>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticMethod");
   b2 = js_2::_callMethodUnchecked1<self::B% /* erasure=self::A, declared=! */>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticGenericMethod", b2);
-  b1 = self::B|staticGetter;
+  b1 = js_2::getProperty<self::B% /* erasure=self::A, declared=! */>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticGetter");
   js_2::_setPropertyUnchecked<self::B% /* erasure=self::A, declared=! */>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticSetter", b2);
-  js_2::_setPropertyUnchecked<self::B% /* erasure=self::A, declared=! */>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticProperty", self::B|staticProperty);
+  js_2::_setPropertyUnchecked<self::B% /* erasure=self::A, declared=! */>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticProperty", js_2::getProperty<self::B% /* erasure=self::A, declared=! */>(js_2::_getPropertyTrustType<core::Object>(_js2::staticInteropGlobalContext, "B"), "staticProperty"));
+  b2 = js_2::_callMethodUnchecked1<self::B% /* erasure=self::A, declared=! */>(b1, "methodWithOptionalArgument", b2);
+  b1 = js_2::_callMethodUnchecked0<self::B% /* erasure=self::A, declared=! */>(b2, "methodWithOptionalArgument");
 }
 
 constants  {

pkg/front_end/testcases/dart2js/extension_types/external.dart.strong.transformed.expect

@@ -26,6 +26,7 @@ extension type B._(A a) {
   external static void set staticSetter(B b);
   external static B get staticProperty;
   external static void set staticProperty(B b);
+  external B methodWithOptionalArgument([B? b]);
 }
 
 void method(A a) {}

pkg/front_end/testcases/dart2js/extension_types/external.dart.textual_outline.expect

@@ -15,6 +15,7 @@ extension type B._(A a) {
   external B.named(int i);
   external B get getter;
   external B get property;
+  external B methodWithOptionalArgument([B? b]);
   external T genericMethod<T extends B>(T t);
   external static A staticField;
   external static A staticMethod();

pkg/front_end/testcases/dart2js/extension_types/external.dart.textual_outline_modelled.expect

@@ -0,0 +1,92 @@
+// 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.
+
+// This test is the same as `external.dart`, except all external members have a
+// `@pragma` annotation.
+
+@JS()
+library static_interop;
+
+import 'dart:js_interop';
+
+@JS()
+@staticInterop
+class A {}
+
+@JS()
+extension type B._(A a) {
+  @annotation
+  external B(A a);
+
+  @annotation
+  external B.named(int i);
+
+  @annotation
+  external A field;
+
+  @annotation
+  external A method();
+
+  @annotation
+  external T genericMethod<T extends B>(T t);
+
+  @annotation
+  external B get getter;
+
+  @annotation
+  external void set setter(B b);
+
+  @annotation
+  external B get property;
+
+  @annotation
+  external void set property(B b);
+
+  @annotation
+  external static A staticField;
+
+  @annotation
+  external static A staticMethod();
+
+  @annotation
+  external static T staticGenericMethod<T extends B>(T t);
+
+  @annotation
+  external static B get staticGetter;
+
+  @annotation
+  external static void set staticSetter(B b);
+
+  @annotation
+  external static B get staticProperty;
+
+  @annotation
+  external static void set staticProperty(B b);
+
+  @annotation
+  external B methodWithOptionalArgument([B? b]);
+}
+
+void method(A a) {
+  B b1 = new B(a);
+  B b2 = new B.named(0);
+  a = b1.field;
+  b1.field = a;
+  a = b1.method();
+  b2 = b2.genericMethod(b2);
+  b1 = b2.getter;
+  b1.setter = b2;
+  b1.property = b2.property;
+  a = B.staticField;
+  B.staticField = a;
+  a = B.staticMethod();
+  b2 = B.staticGenericMethod(b2);
+  b1 = B.staticGetter;
+  B.staticSetter = b2;
+  B.staticProperty = B.staticProperty;
+  b2 = b1.methodWithOptionalArgument(b2);
+  b1 = b2.methodWithOptionalArgument();
+}
+
+const annotation = pragma('a pragma');