Don't crash on deserialized type inference.

pkg/compiler/lib/src/serialization/resolved_ast_serialization.dart

 // Copyright (c) 2016, 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.
 
 library dart2js.serialization.resolved_ast;
 
 import '../common.dart';
 import '../common/resolution.dart';
 import '../constants/expressions.dart';
 import '../dart_types.dart';
@@ skipping 276 matching lines @@
 
   @override
   visitLabel(Label node) {
     visitNode(node);
     LabelDefinition labelDefinition = elements.getLabelDefinition(node);
     if (labelDefinition != null) {
       getNodeDataEncoder(node)
           .setInt(Key.LABEL_DEFINITION, getLabelDefinitionId(labelDefinition));
     }
   }
+
+  @override
+  visitFunctionExpression(FunctionExpression node) {
+    visitExpression(node);
+    Element function = elements.getFunctionDefinition(node);
+    if (function != null && function.isFunction && function.isLocal) {
+      // Mark root nodes of local functions; these need their own ResolvedAst.
+      getNodeDataEncoder(node).setElement(Key.FUNCTION, function);
+    }
+  }
 }
 
 class ResolvedAstDeserializer {
   /// Find the [Token] at [offset] searching through successors of [token].
   static Token findTokenInStream(Token token, int offset) {
     while (token.charOffset <= offset && token.next != token) {
       if (token.charOffset == offset) {
         return token;
       }
       token = token.next;
     }
     return null;
   }
 
-  /// Deserializes the [ResolvedAst] for [element] from [objectDecoder].
+  /// Deserializes the [ResolvedAst]s for [element] and its nested local
+  /// functions from [objectDecoder] and adds these to [resolvedAstMap].
   /// [parsing] and [getBeginToken] are used for parsing the [Node] for
   /// [element] from its source code.
-  static ResolvedAst deserialize(
+  static void deserialize(
       Element element,
       ObjectDecoder objectDecoder,
       ParsingContext parsing,
       Token getBeginToken(Uri uri, int charOffset),
-      DeserializerPlugin nativeDataDeserializer) {
+      DeserializerPlugin nativeDataDeserializer,
+      Map<Element, ResolvedAst> resolvedAstMap) {
     ResolvedAstKind kind =
         objectDecoder.getEnum(Key.KIND, ResolvedAstKind.values);
     switch (kind) {
       case ResolvedAstKind.PARSED:
-        return deserializeParsed(element, objectDecoder, parsing, getBeginToken,
-            nativeDataDeserializer);
+        deserializeParsed(element, objectDecoder, parsing, getBeginToken,
+            nativeDataDeserializer, resolvedAstMap);
+        break;
       case ResolvedAstKind.DEFAULT_CONSTRUCTOR:
       case ResolvedAstKind.FORWARDING_CONSTRUCTOR:
-        return new SynthesizedResolvedAst(element, kind);
+        resolvedAstMap[element] = new SynthesizedResolvedAst(element, kind);
+        break;
     }
   }
 
   /// Deserialize a [ResolvedAst] that is defined in terms of an AST together
   /// with [TreeElements].

[Siggi Cherem (dart-lang), 2016/05/02 16:21:43]

let's update the comment to say that this deserializes the resolved AST of an
element and it's nested elements (maybe clarify also that the outer element is a
function/procedure, and that nested elements are closures)?

[Johnni Winther, 2016/05/04 09:56:25]

Done.

-  static ResolvedAst deserializeParsed(
+  static void deserializeParsed(
       Element element,
       ObjectDecoder objectDecoder,
       ParsingContext parsing,
       Token getBeginToken(Uri uri, int charOffset),
-      DeserializerPlugin nativeDataDeserializer) {
+      DeserializerPlugin nativeDataDeserializer,
+      Map<Element, ResolvedAst> resolvedAstMap) {
     CompilationUnitElement compilationUnit = element.compilationUnit;
     DiagnosticReporter reporter = parsing.reporter;
 
     /// Returns the first [Token] for parsing the [Node] for [element].
     Token readBeginToken() {
       Uri uri = objectDecoder.getUri(Key.URI);
       int charOffset = objectDecoder.getInt(Key.OFFSET);
       Token beginToken = getBeginToken(uri, charOffset);
       if (beginToken == null) {
         reporter.internalError(
@@ skipping 195 matching lines @@
     jumpTargetLabels.forEach((JumpTargetX jumpTarget, List<int> labelIds) {
       if (labelIds.isEmpty) return;
       LinkBuilder<LabelDefinition> linkBuilder =
           new LinkBuilder<LabelDefinition>();
       for (int labelId in labelIds) {
         linkBuilder.addLast(labelDefinitions[labelId]);
       }
       jumpTarget.labels = linkBuilder.toLink();
     });
 
-    ListDecoder dataDecoder = objectDecoder.getList(Key.DATA);
+    ListDecoder dataDecoder = objectDecoder.getList(Key.DATA, isOptional: true);
     if (dataDecoder != null) {
       for (int i = 0; i < dataDecoder.length; i++) {
         ObjectDecoder objectDecoder = dataDecoder.getObject(i);
         int id = objectDecoder.getInt(Key.ID);
         Node node = nodeList[id];
         Element nodeElement = deserializeElementReference(
             element, Key.ELEMENT, Key.NAME, objectDecoder,
             isOptional: true);
         if (nodeElement != null) {
           elements[node] = nodeElement;
@@ skipping 50 matching lines @@
           elements.registerTargetLabel(node, labelDefinitions[targetLabelId]);
         }
         ObjectDecoder nativeDataDecoder =
             objectDecoder.getObject(Key.NATIVE, isOptional: true);
         if (nativeDataDecoder != null) {
           var nativeData = nativeDataDeserializer.onData(nativeDataDecoder);
           if (nativeData != null) {
             elements.registerNativeData(node, nativeData);
           }
         }
+        FunctionElement function =
+            objectDecoder.getElement(Key.FUNCTION, isOptional: true);
+        if (function != null) {
+          FunctionExpression functionExpression = node;
+          resolvedAstMap[function] = new ParsedResolvedAst(

[Siggi Cherem (dart-lang), 2016/05/02 16:21:43]

do we need to assert that the key doesn't exist already? (seems like an
invariant in how we are using this from serialization_helper.)

Alternatively, instead of passing in the output-map, we could return a fresh map
each time you call this function. It's more wasted memory, but that might be
fine, then here we don't need to care about any invariants about the map.

[Johnni Winther, 2016/05/04 09:56:25]

Invariant test added!

+              function, functionExpression, functionExpression.body, elements);
+        }
       }
     }
-    return new ParsedResolvedAst(element, root, body, elements);
+    resolvedAstMap[element] =
+        new ParsedResolvedAst(element, root, body, elements);
   }
 }