fix to run against latest analyzer

lib/src/codegen/reify_coercions.dart

Index: lib/src/codegen/reify_coercions.dart
diff --git a/lib/src/codegen/reify_coercions.dart b/lib/src/codegen/reify_coercions.dart
index 4ed5003fdbf6ab9e0cc53a63cbc53a8a342f273d..f38e039aba799c26b67fdb1bfadab7873455aaed 100644
--- a/lib/src/codegen/reify_coercions.dart
+++ b/lib/src/codegen/reify_coercions.dart
@@ -6,7 +6,10 @@ import 'package:analyzer/analyzer.dart' as analyzer;
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
+import 'package:analyzer/src/dart/ast/ast.dart' show FunctionBodyImpl;
 import 'package:analyzer/src/dart/ast/utilities.dart' show NodeReplacer;
+import 'package:analyzer/src/dart/element/type.dart' show DynamicTypeImpl;
+import 'package:analyzer/src/generated/parser.dart' show ResolutionCopier;
 import 'package:analyzer/src/task/strong/info.dart';
 import 'package:logging/logging.dart' as logger;
 
@@ -30,41 +33,71 @@ class NewTypeIdDesc {
 // This class implements a pass which modifies (in place) the ast replacing
 // abstract coercion nodes with their dart implementations.
 class CoercionReifier extends analyzer.GeneralizingAstVisitor<Object> {
+  final cloner = new _TreeCloner();
 
-  CoercionReifier();
-
-  /// This should be the entry point for this class.
+  /// Makes coercions explicit in the resolved AST, and returns the new AST.
   ///
-  /// Entering via the visit functions directly may not do the right
-  /// thing with respect to discharging the collected definitions.
+  /// This should be the entry point for this class.
+  /// Entering via the visit functions directly will incorrectly mutate the AST.
   ///
-  /// Returns the set of new type identifiers added by the reifier
-  void reify(List<CompilationUnit> units) {
+  /// Returns the new compilation units.
+  List<CompilationUnit> reify(List<CompilationUnit> units) {
+    // Copy the AST before modifying it.
+    units = units.map(_clone).toList();
+    // Visit the AST and make coercions explicit.
     units.forEach(visitCompilationUnit);
+    return units;
   }
 
   @override
-  Object visitExpression(Expression node) {
-    var info = CoercionInfo.get(node);
-    if (info is DownCast) {
-      return _visitDownCast(info, node);
+  visitExpression(Expression node) {
+    var coercion = CoercionInfo.get(node);
+    if (coercion is DownCast) {
+      return _visitDownCast(coercion, node);
     }
     return super.visitExpression(node);
   }
 
-  ///////////////// Private //////////////////////////////////
+  @override
+  visitForEachStatement(ForEachStatement node) {
+    // Visit other children.
+    node.iterable.accept(this);
+    node.body.accept(this);
+
+    // If needed, assert a cast inside the body before the variable is read.
+    var variable = node.identifier ?? node.loopVariable.identifier;
+    var coercion = CoercionInfo.get(variable);
+    if (coercion is DownCast) {
+      // Build the cast. We will place this cast in the body, so need to clone
+      // the variable's AST node and clear out its static type (otherwise we
+      // will optimize away the cast).
+      var cast = _castExpression(
+          _clone(variable)..staticType = DynamicTypeImpl.instance,
+          coercion.convertedType);
+
+      var body = node.body;
+      var blockBody = <Statement>[RawAstBuilder.expressionStatement(cast)];
+      if (body is Block) {
+        blockBody.addAll(body.statements);
+      } else {
+        blockBody.add(body);
+      }
+      _replaceNode(node, body, RawAstBuilder.block(blockBody));
+    }
+  }
 
-  Object _visitDownCast(DownCast node, Expression expr) {
-    var parent = expr.parent;
+  void _visitDownCast(DownCast node, Expression expr) {
     expr.visitChildren(this);
-    Expression newE = coerceExpression(expr, node);
-    if (!identical(expr, newE)) {
-      var replaced = parent.accept(new NodeReplacer(expr, newE));
+    _replaceNode(expr.parent, expr, coerceExpression(expr, node));
+  }
+
+  void _replaceNode(AstNode parent, AstNode oldNode, AstNode newNode) {
+    if (!identical(oldNode, newNode)) {
+      var replaced = parent.accept(new NodeReplacer(oldNode, newNode));
       // It looks like NodeReplacer will always return true.
       // It does throw IllegalArgumentException though, if child is not found.
       assert(replaced);
     }
-    return null;
   }
 
   /// Coerce [e] using [c], returning a new expression.
@@ -76,8 +109,6 @@ class CoercionReifier extends analyzer.GeneralizingAstVisitor<Object> {
     return _castExpression(e, node.convertedType);
   }
 
-  ///////////////// Private //////////////////////////////////
-
   Expression _castExpression(Expression e, DartType toType) {
     // We use an empty name in the AST, because the JS code generator only cares
     // about the target type. It does not look at the AST name.
@@ -87,4 +118,53 @@ class CoercionReifier extends analyzer.GeneralizingAstVisitor<Object> {
     cast.staticType = toType;
     return cast;
   }
+
+  /*=T*/ _clone/*<T extends AstNode>*/(/*=T*/ node) {
+    var copy = node.accept(cloner);
+    ResolutionCopier.copyResolutionData(node, copy);
+    return copy;
+  }
+}
+
+class _TreeCloner extends analyzer.AstCloner {
+  void _cloneProperties(AstNode clone, AstNode node) {
+    if (clone != null) {
+      CoercionInfo.set(clone, CoercionInfo.get(node));
+      DynamicInvoke.set(clone, DynamicInvoke.get(node));
+    }
+  }
+
+  @override
+  AstNode cloneNode(AstNode node) {
+    var clone = super.cloneNode(node);
+    _cloneProperties(clone, node);
+    return clone;
+  }
+
+  @override
+  List cloneNodeList(List list) {
+    var clone = super.cloneNodeList(list);
+    for (int i = 0, len = list.length; i < len; i++) {
+      _cloneProperties(clone[i], list[i]);
+    }
+    return clone;
+  }
+
+  // TODO(jmesserly): ResolutionCopier is not copying this yet.
+  @override
+  BlockFunctionBody visitBlockFunctionBody(BlockFunctionBody node) {
+    var clone = super.visitBlockFunctionBody(node);
+    (clone as FunctionBodyImpl).localVariableInfo =
+        (node as FunctionBodyImpl).localVariableInfo;
+    return clone;
+  }
+
+  @override
+  ExpressionFunctionBody visitExpressionFunctionBody(
+      ExpressionFunctionBody node) {
+    var clone = super.visitExpressionFunctionBody(node);
+    (clone as FunctionBodyImpl).localVariableInfo =
+        (node as FunctionBodyImpl).localVariableInfo;
+    return clone;
+  }
 }