[analyzer] Dot shorthands: Selector chains, add mixin to PropertyAccess and MethodInvocation.

For supporting selector chains, I've added the DotShorthandMixin to PropertyAccess and MethodInvocation, and marked the `isDotShorthand` flag when it's the outer most selector whose context type we care about saving.

Multiple language tests passing + added some unit tests for some simple selector chain cases.

Bug: #59835
Change-Id: I7571eb22b4213be895a756b89ecf74f65c4cced5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/423382
Commit-Queue: Kallen Tu <[email protected]>
Reviewed-by: Paul Berry <[email protected]>
Reviewed-by: Chloe Stefantsova <[email protected]>

Author: kallentu

pkg/analyzer/lib/src/dart/ast/ast.dart

@@ -12051,7 +12051,7 @@ abstract final class MethodInvocation
 }
 
 final class MethodInvocationImpl extends InvocationExpressionImpl
-    with NullShortableExpressionImpl
+    with NullShortableExpressionImpl, DotShorthandMixin
     implements MethodInvocation {
   ExpressionImpl? _target;
 
@@ -14471,7 +14471,7 @@ abstract final class PropertyAccess
 }
 
 final class PropertyAccessImpl extends CommentReferableExpressionImpl
-    with NullShortableExpressionImpl
+    with NullShortableExpressionImpl, DotShorthandMixin
     implements PropertyAccess {
   ExpressionImpl? _target;
 

pkg/analyzer/lib/src/generated/resolver.dart

@@ -3323,6 +3323,12 @@ class ResolverVisitor extends ThrowingAstVisitor<void>
     TypeImpl contextType = UnknownInferredType.instance,
   }) {
     inferenceLogWriter?.enterExpression(node, contextType);
+
+    // If [isDotShorthand] is set, cache the context type for resolution.
+    if (isDotShorthand(node)) {
+      pushDotShorthandContext(node, SharedTypeSchemaView(contextType));
+    }
+
     checkUnreachableNode(node);
     var whyNotPromotedArguments =
         <Map<SharedTypeView, NonPromotionReason> Function()>[];
@@ -3362,6 +3368,11 @@ class ResolverVisitor extends ThrowingAstVisitor<void>
     );
     _insertImplicitCallReference(replacement, contextType: contextType);
     nullSafetyDeadCodeVerifier.verifyMethodInvocation(node);
+
+    if (isDotShorthand(node)) {
+      popDotShorthandContext();
+    }
+
     inferenceLogWriter?.exitExpression(node);
   }
 
@@ -3627,6 +3638,12 @@ class ResolverVisitor extends ThrowingAstVisitor<void>
     TypeImpl contextType = UnknownInferredType.instance,
   }) {
     inferenceLogWriter?.enterExpression(node, contextType);
+
+    // If [isDotShorthand] is set, cache the context type for resolution.
+    if (isDotShorthand(node)) {
+      pushDotShorthandContext(node, SharedTypeSchemaView(contextType));
+    }
+
     checkUnreachableNode(node);
 
     var target = node.target;
@@ -3640,6 +3657,11 @@ class ResolverVisitor extends ThrowingAstVisitor<void>
 
     checkUnreachableNode(node.propertyName);
     _resolvePropertyAccessRhs(node, contextType);
+
+    if (isDotShorthand(node)) {
+      popDotShorthandContext();
+    }
+
     inferenceLogWriter?.exitExpression(node);
   }
 

pkg/analyzer/test/src/dart/resolution/dot_shorthand_constructor_invocation_test.dart

@@ -17,6 +17,74 @@ main() {
 @reflectiveTest
 class DotShorthandConstructorInvocationResolutionTest
     extends PubPackageResolutionTest {
+  test_chain_method() async {
+    await assertNoErrorsInCode(r'''
+class C {
+  int x;
+  C(this.x);
+  C method() => C(1);
+}
+
+void main() {
+  C c = .new(1).method();
+  print(c);
+}
+''');
+
+    var identifier = findNode.singleDotShorthandConstructorInvocation;
+    assertResolvedNodeText(identifier, r'''
+DotShorthandConstructorInvocation
+  period: .
+  constructorName: SimpleIdentifier
+    token: new
+    element: <testLibraryFragment>::@class::C::@constructor::new#element
+    staticType: null
+  argumentList: ArgumentList
+    leftParenthesis: (
+    arguments
+      IntegerLiteral
+        literal: 1
+        correspondingParameter: <testLibraryFragment>::@class::C::@constructor::new::@parameter::x#element
+        staticType: int
+    rightParenthesis: )
+  staticType: C
+''');
+  }
+
+  test_chain_property() async {
+    await assertNoErrorsInCode(r'''
+class C {
+  int x;
+  C(this.x);
+  C get property => C(1);
+}
+
+void main() {
+  C c = .new(1).property;
+  print(c);
+}
+''');
+
+    var identifier = findNode.singleDotShorthandConstructorInvocation;
+    assertResolvedNodeText(identifier, r'''
+DotShorthandConstructorInvocation
+  period: .
+  constructorName: SimpleIdentifier
+    token: new
+    element: <testLibraryFragment>::@class::C::@constructor::new#element
+    staticType: null
+  argumentList: ArgumentList
+    leftParenthesis: (
+    arguments
+      IntegerLiteral
+        literal: 1
+        correspondingParameter: <testLibraryFragment>::@class::C::@constructor::new::@parameter::x#element
+        staticType: int
+    rightParenthesis: )
+  staticType: C
+''');
+  }
+
   test_constructor_named() async {
     await assertNoErrorsInCode(r'''
 class C {

pkg/analyzer/test/src/dart/resolution/dot_shorthand_invocation_test.dart

@@ -222,6 +222,68 @@ FunctionExpressionInvocation
 ''');
   }
 
+  test_chain_method() async {
+    await assertNoErrorsInCode(r'''
+class C {
+  static C member() => C(1);
+  int x;
+  C(this.x);
+  C method() => C(1);
+}
+
+void main() {
+  C c = .member().method();
+  print(c);
+}
+''');
+
+    var identifier = findNode.singleDotShorthandInvocation;
+    assertResolvedNodeText(identifier, r'''
+DotShorthandInvocation
+  period: .
+  memberName: SimpleIdentifier
+    token: member
+    element: <testLibraryFragment>::@class::C::@method::member#element
+    staticType: C Function()
+  argumentList: ArgumentList
+    leftParenthesis: (
+    rightParenthesis: )
+  staticInvokeType: C Function()
+  staticType: C
+''');
+  }
+
+  test_chain_property() async {
+    await assertNoErrorsInCode(r'''
+class C {
+  static C member() => C(1);
+  int x;
+  C(this.x);
+  C get property => C(1);
+}
+
+void main() {
+  C c = .member().property;
+  print(c);
+}
+''');
+
+    var identifier = findNode.singleDotShorthandInvocation;
+    assertResolvedNodeText(identifier, r'''
+DotShorthandInvocation
+  period: .
+  memberName: SimpleIdentifier
+    token: member
+    element: <testLibraryFragment>::@class::C::@method::member#element
+    staticType: C Function()
+  argumentList: ArgumentList
+    leftParenthesis: (
+    rightParenthesis: )
+  staticInvokeType: C Function()
+  staticType: C
+''');
+  }
+
   test_equality() async {
     await assertNoErrorsInCode('''
 class C {

pkg/analyzer/test/src/dart/resolution/dot_shorthand_property_access_test.dart

@@ -17,6 +17,60 @@ main() {
 @reflectiveTest
 class DotShorthandPropertyAccessResolutionTest
     extends PubPackageResolutionTest {
+  test_chain_method() async {
+    await assertNoErrorsInCode(r'''
+class C {
+  static C get member => C(1);
+  int x;
+  C(this.x);
+  C method() => C(1);
+}
+
+void main() {
+  C c = .member.method();
+  print(c);
+}
+''');
+
+    var identifier = findNode.singleDotShorthandPropertyAccess;
+    assertResolvedNodeText(identifier, r'''
+DotShorthandPropertyAccess
+  period: .
+  propertyName: SimpleIdentifier
+    token: member
+    element: <testLibraryFragment>::@class::C::@getter::member#element
+    staticType: C
+  staticType: C
+''');
+  }
+
+  test_chain_property() async {
+    await assertNoErrorsInCode(r'''
+class C {
+  static C get member => C(1);
+  int x;
+  C(this.x);
+  C get property => C(1);
+}
+
+void main() {
+  C c = .member.property;
+  print(c);
+}
+''');
+
+    var identifier = findNode.singleDotShorthandPropertyAccess;
+    assertResolvedNodeText(identifier, r'''
+DotShorthandPropertyAccess
+  period: .
+  propertyName: SimpleIdentifier
+    token: member
+    element: <testLibraryFragment>::@class::C::@getter::member#element
+    staticType: C
+  staticType: C
+''');
+  }
+
   test_class_basic() async {
     await assertNoErrorsInCode('''
 class C {