Implement KernelNoSuchMethodResolver.

pkg/compiler/lib/src/resolution/no_such_method_resolver.dart

+// Copyright (c) 2017, 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.
+
+import '../common/names.dart' show Identifiers, Names;
+import '../elements/elements.dart';
+import '../js_backend/no_such_method_registry.dart';
+import '../tree/tree.dart';
+
+/// AST-based implementation of [NoSuchMethodResolver].
+class ResolutionNoSuchMethodResolver implements NoSuchMethodResolver {
+  bool hasForwardingSyntax(MethodElement element) {
+    // At this point we know that this is signature-compatible with
+    // Object.noSuchMethod, but it may have more than one argument as long as
+    // it only has one required argument.
+    if (!element.hasResolvedAst) {
+      // TODO(johnniwinther): Why do we see unresolved elements here?
+      return false;
+    }
+    ResolvedAst resolvedAst = element.resolvedAst;
+    if (resolvedAst.kind != ResolvedAstKind.PARSED) {
+      return false;
+    }
+    String param = element.parameters.first.name;
+    Statement body = resolvedAst.body;
+    Expression expr;
+    if (body is Return && body.isArrowBody) {
+      expr = body.expression;
+    } else if (body is Block &&
+        !body.statements.isEmpty &&
+        body.statements.nodes.tail.isEmpty) {
+      Statement stmt = body.statements.nodes.head;
+      if (stmt is Return && stmt.hasExpression) {
+        expr = stmt.expression;
+      }
+    }
+    if (expr is Send && expr.isTypeCast) {
+      Send sendExpr = expr;
+      var typeAnnotation = sendExpr.typeAnnotationFromIsCheckOrCast;
+      var typeName = typeAnnotation.asNominalTypeAnnotation()?.typeName;
+      if (typeName is Identifier && typeName.source == "dynamic") {
+        expr = sendExpr.receiver;
+      }
+    }
+    if (expr is Send &&
+        expr.isSuperCall &&
+        expr.selector is Identifier &&
+        (expr.selector as Identifier).source == Identifiers.noSuchMethod_) {
+      var arg = expr.arguments.head;
+      if (expr.arguments.tail.isEmpty &&
+          arg is Send &&
+          arg.argumentsNode == null &&
+          arg.receiver == null &&
+          arg.selector is Identifier &&
+          arg.selector.source == param) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  bool hasThrowingSyntax(MethodElement element) {
+    if (!element.hasResolvedAst) {
+      // TODO(johnniwinther): Why do we see unresolved elements here?
+      return false;
+    }
+    ResolvedAst resolvedAst = element.resolvedAst;
+    if (resolvedAst.kind != ResolvedAstKind.PARSED) {
+      return false;
+    }
+    Statement body = resolvedAst.body;
+    if (body is Return && body.isArrowBody) {
+      if (body.expression is Throw) {
+        return true;
+      }
+    } else if (body is Block &&
+        !body.statements.isEmpty &&
+        body.statements.nodes.tail.isEmpty) {
+      if (body.statements.nodes.head is ExpressionStatement) {
+        ExpressionStatement stmt = body.statements.nodes.head;
+        return stmt.expression is Throw;
+      }
+    }
+    return false;
+  }
+
+  MethodElement getSuperNoSuchMethod(MethodElement method) {
+    return method.enclosingClass.lookupSuperByName(Names.noSuchMethod_);
+  }
+}