Resolve ordering issues.

pkg/analyzer/lib/src/task/dart.dart

 // Copyright (c) 2015, 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 analyzer.src.task.dart;
 
 import 'dart:collection';
 
 import 'package:analyzer/src/context/cache.dart';
 import 'package:analyzer/src/generated/ast.dart';
@@ skipping 135 matching lines @@
 /**
  * The sources representing the combined import/export closure of a library.
  * The [Source]s include only library sources, not their units.
  *
  * The result is only available for [Source]s representing a library.
  */
 final ListResultDescriptor<Source> IMPORT_EXPORT_SOURCE_CLOSURE =
     new ListResultDescriptor<Source>('IMPORT_EXPORT_SOURCE_CLOSURE', null);
 
 /**
- * The errors produced while inferring the type of a static variable.
+ * A list of the [LibraryElement]s that make up the strongly connected
+ * component in the import/export graph in which the target resides.
  *
- * The list will be empty if there were no errors, but will not be `null`.
+ * Only non-empty in strongMode
  *
- * The result is only available for [VariableElement]s, and only when strong
- * mode is enabled.
  */
-final ListResultDescriptor<AnalysisError> INFER_STATIC_VARIABLE_ERRORS =
-    new ListResultDescriptor<AnalysisError>(
-        'INFER_STATIC_VARIABLE_ERRORS', AnalysisError.NO_ERRORS);
+final ListResultDescriptor<LibraryElement> LIBRARY_CYCLE =
+    new ListResultDescriptor<LibraryElement>('LIBRARY_CYCLE', null);
 
 /**
- * The errors produced while inferring the types of all of the static variables
- * in a compilation unit.
+ * A list of the [CompilationUnitElement]s (including all parts) that make up
+ * the strongly connected component in the import/export graph in which the
+ * target resides.
  *
- * The list will be empty if there were no errors, but will not be `null`.
+ * Only non-empty in strongMode
  *
- * The result is only available for [LibrarySpecificUnit]s.
  */
-final ListResultDescriptor<AnalysisError> INFER_STATIC_VARIABLE_TYPES_ERRORS =
-    new ListResultDescriptor<AnalysisError>(
-        'INFER_STATIC_VARIABLE_TYPES_ERRORS', AnalysisError.NO_ERRORS);
+final ListResultDescriptor<CompilationUnitElement> LIBRARY_CYCLE_UNITS =
+    new ListResultDescriptor<CompilationUnitElement>(
+        'LIBRARY_CYCLE_UNITS', null);
+
+/**
+ * A list of the [CompilationUnitElement]s that comprise all of the parts and
+ * libraries in the direct import/export dependencies of the library cycle
+ * of the target, with the intra-component dependencies excluded.
+ *
+ * Only non-empty in strongMode
+ *
+ */
+final ListResultDescriptor<CompilationUnitElement> LIBRARY_CYCLE_DEPENDENCIES =
+    new ListResultDescriptor<CompilationUnitElement>(
+        'LIBRARY_CYCLE_DEPENDENCIES', null);
 
 /**
  * A list of the [VariableElement]s whose type should be inferred that another
  * inferable static variable (the target) depends on.
  *
  * The result is only available for [VariableElement]s, and only when strong
  * mode is enabled.
  */
 final ListResultDescriptor<
         VariableElement> INFERABLE_STATIC_VARIABLE_DEPENDENCIES =
@@ skipping 107 matching lines @@
  *
  * The list will be empty if there were no errors, but will not be `null`.
  *
  * The result is only available for [Source]s representing a compilation unit.
  */
 final ListResultDescriptor<AnalysisError> PARSE_ERRORS =
     new ListResultDescriptor<AnalysisError>(
         'PARSE_ERRORS', AnalysisError.NO_ERRORS);
 
 /**
- * The errors produced while resolving references outside of function bodies.
- *
- * The list will be empty if there were no errors, but will not be `null`.
- *
- * The result is only available for [LibrarySpecificUnit]s.
- */
-final ListResultDescriptor<AnalysisError> PARTIALLY_RESOLVE_REFERENCES_ERRORS =
-    new ListResultDescriptor<AnalysisError>(
-        'PARTIALLY_RESOLVE_REFERENCES_ERRORS', AnalysisError.NO_ERRORS);
-
-/**
  * The names (resolved and not) referenced by a unit.
  *
  * The result is only available for [Source]s representing a compilation unit.
  */
 final ResultDescriptor<ReferencedNames> REFERENCED_NAMES =
     new ResultDescriptor<ReferencedNames>('REFERENCED_NAMES', null);
 
 /**
- * The errors produced while resolving the function bodies within a compilation
- * unit.
+ * The errors produced while resolving a full compilation unit. 
  *
  * The list will be empty if there were no errors, but will not be `null`.
  *
  * The result is only available for [LibrarySpecificUnit]s.
  */
-final ListResultDescriptor<AnalysisError> RESOLVE_FUNCTION_BODIES_ERRORS =
+final ListResultDescriptor<AnalysisError> RESOLVE_UNIT_ERRORS =
     new ListResultDescriptor<AnalysisError>(
-        'RESOLVE_FUNCTION_BODIES_ERRORS', AnalysisError.NO_ERRORS);
+        'RESOLVE_UNIT_ERRORS', AnalysisError.NO_ERRORS);
 
 /**
  * The errors produced while resolving type names.
  *
  * The list will be empty if there were no errors, but will not be `null`.
  *
  * The result is only available for [LibrarySpecificUnit]s.
  */
 final ListResultDescriptor<AnalysisError> RESOLVE_TYPE_NAMES_ERRORS =
     new ListResultDescriptor<AnalysisError>(
@@ skipping 60 matching lines @@
  * that is true of a [RESOLVED_UNIT5].
  *
  * The result is only available for [LibrarySpecificUnit]s.
  */
 final ResultDescriptor<CompilationUnit> RESOLVED_UNIT6 =
     new ResultDescriptor<CompilationUnit>('RESOLVED_UNIT6', null,
         cachingPolicy: AST_CACHING_POLICY);
 
 /**
  * The resolved [CompilationUnit] associated with a compilation unit in which
- * the types of class members have been inferred in addition to everything that
- * is true of a [RESOLVED_UNIT7].
+ * the right hand sides of instance variables have been re-resolved in addition
+ * to everything that is true of a [RESOLVED_UNIT6].
  *
  * The result is only available for [LibrarySpecificUnit]s.
  */
+// TODO(leafp): Rename and renumber if this persists
 final ResultDescriptor<CompilationUnit> RESOLVED_UNIT7 =
     new ResultDescriptor<CompilationUnit>('RESOLVED_UNIT7', null,
         cachingPolicy: AST_CACHING_POLICY);
 
 /**
- * The resolved [CompilationUnit] associated with a compilation unit, with
- * constants not yet resolved.
+ * The resolved [CompilationUnit] associated with a compilation unit in which
+ * the types of class members have been inferred in addition to everything that
+ * is true of a [RESOLVED_UNIT8].
  *
  * The result is only available for [LibrarySpecificUnit]s.
  */
 final ResultDescriptor<CompilationUnit> RESOLVED_UNIT8 =
     new ResultDescriptor<CompilationUnit>('RESOLVED_UNIT8', null,
         cachingPolicy: AST_CACHING_POLICY);
 
 /**
+ * The resolved [CompilationUnit] associated with a compilation unit, with
+ * constants not yet resolved.
+ *
+ * The result is only available for [LibrarySpecificUnit]s.
+ */
+final ResultDescriptor<CompilationUnit> RESOLVED_UNIT9 =
+    new ResultDescriptor<CompilationUnit>('RESOLVED_UNIT9', null,
+        cachingPolicy: AST_CACHING_POLICY);
+
+/**
  * The errors produced while scanning a compilation unit.
  *
  * The list will be empty if there were no errors, but will not be `null`.
  *
  * The result is only available for [Source]s representing a compilation unit.
  */
 final ListResultDescriptor<AnalysisError> SCAN_ERRORS =
     new ListResultDescriptor<AnalysisError>(
         'SCAN_ERRORS', AnalysisError.NO_ERRORS);
 
@@ skipping 1031 matching lines @@
       AnalysisContext context, AnalysisTarget target) {
     return new BuildTypeProviderTask(context, target);
   }
 }
 
 /**
  * A task that computes [CONSTANT_DEPENDENCIES] for a constant.
  */
 class ComputeConstantDependenciesTask extends ConstantEvaluationAnalysisTask {
   /**
-   * The name of the [RESOLVED_UNIT8] input.
+   * The name of the [RESOLVED_UNIT9] input.
    */
   static const String UNIT_INPUT = 'UNIT_INPUT';
 
   /**
    * The name of the [TYPE_PROVIDER] input.
    */
   static const String TYPE_PROVIDER_INPUT = 'TYPE_PROVIDER_INPUT';
 
   static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
       'ComputeConstantDependenciesTask',
@@ skipping 35 matching lines @@
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the
    * given [target].
    */
   static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
     if (target is Element) {
       CompilationUnitElementImpl unit = target
           .getAncestor((Element element) => element is CompilationUnitElement);
       return <String, TaskInput>{
-        UNIT_INPUT: RESOLVED_UNIT8
+        UNIT_INPUT: RESOLVED_UNIT9
             .of(new LibrarySpecificUnit(unit.librarySource, target.source)),
         TYPE_PROVIDER_INPUT: TYPE_PROVIDER.of(AnalysisContextTarget.request)
       };
     } else if (target is ConstantEvaluationTarget_Annotation) {
       return <String, TaskInput>{
-        UNIT_INPUT: RESOLVED_UNIT8
+        UNIT_INPUT: RESOLVED_UNIT9
             .of(new LibrarySpecificUnit(target.librarySource, target.source)),
         TYPE_PROVIDER_INPUT: TYPE_PROVIDER.of(AnalysisContextTarget.request)
       };
     }
     throw new AnalysisException(
         'Cannot build inputs for a ${target.runtimeType}');
   }
 
   /**
    * Create a [ComputeConstantDependenciesTask] based on the given [target] in
@@ skipping 178 matching lines @@
    * Create a [ComputeInferableStaticVariableDependenciesTask] based on the
    * given [target] in the given [context].
    */
   static ComputeInferableStaticVariableDependenciesTask createTask(
       AnalysisContext context, AnalysisTarget target) {
     return new ComputeInferableStaticVariableDependenciesTask(context, target);
   }
 }
 
 /**
+ * A task that computes the [LIBRARY_CYCLE_DEPENDENCIES] for a
+ * compilation unit
+ */
+class ComputeLibraryCycleDependenciesTask extends SourceBasedAnalysisTask {
+  /**
+   * The name of the [LIBRARY_CYCLE] input.
+   */
+  static const String LIBRARY_CYCLE_INPUT = 'LIBRARY_CYCLE_INPUT';
+
+  static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
+      'ComputeLibraryCycleDependenciesTask',
+      createTask,
+      buildInputs,
+      <ResultDescriptor>[LIBRARY_CYCLE_DEPENDENCIES]);
+
+  ComputeLibraryCycleDependenciesTask(
+      InternalAnalysisContext context, AnalysisTarget target)
+      : super(context, target);
+
+  @override
+  TaskDescriptor get descriptor => DESCRIPTOR;
+
+  @override
+  void internalPerform() {
+    if (context.analysisOptions.strongMode) {
+      //
+      // Prepare inputs.
+      //
+      List<LibraryElement> scc = getRequiredInput(LIBRARY_CYCLE_INPUT);
+
+      Set<LibraryElement> filter = new Set<LibraryElement>.from(scc);
+      Set<CompilationUnitElement> deps = new Set<CompilationUnitElement>();
+      void addLibrary(l) {
+        if (!filter.contains(l)) {
+          deps.addAll(l.units);
+        }
+      }
+      for (LibraryElement l in scc) {
+        l.importedLibraries.forEach(addLibrary);
+        l.exportedLibraries.forEach(addLibrary);
+      }
+      outputs[LIBRARY_CYCLE_DEPENDENCIES] = deps.toList();
+    } else {
+      outputs[LIBRARY_CYCLE_DEPENDENCIES] = [];
+    }
+  }
+
+  /**
+   * Return a map from the names of the inputs of this kind of task to the task
+   * input descriptors describing those inputs for a task with the
+   * given [target].
+   */
+  static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
+    LibrarySpecificUnit unit = target;
+    return <String, TaskInput>{LIBRARY_CYCLE_INPUT: LIBRARY_CYCLE.of(unit)};
+  }
+
+  /**
+   * Create a [ComputeLibraryCycleDependenciesTask] based on the
+   * given [target] in the given [context].
+   */
+  static ComputeLibraryCycleDependenciesTask createTask(
+      AnalysisContext context, AnalysisTarget target) {
+    return new ComputeLibraryCycleDependenciesTask(context, target);
+  }
+}
+
+/**
+ * A task that computes the [LIBRARY_CYCLE] for a
+ * library element.  Also computes the [LIBRARY_CYCLE_UNITS]
+ */
+class ComputeLibraryCycleTask extends SourceBasedAnalysisTask {
+  /**
+   * The name of the [LIBRARY_ELEMENT2] input.
+   */
+  static const String UNIT_INPUT = 'UNIT_INPUT';
+
+  static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
+      'ComputeLibraryCycleForUnitTask',
+      createTask,
+      buildInputs,
+      <ResultDescriptor>[LIBRARY_CYCLE, LIBRARY_CYCLE_UNITS]);
+
+  ComputeLibraryCycleTask(
+      InternalAnalysisContext context, AnalysisTarget target)
+      : super(context, target);
+
+  @override
+  TaskDescriptor get descriptor => DESCRIPTOR;
+
+  @override
+  void internalPerform() {
+    //
+    // Record outputs.
+    //
+    if (context.analysisOptions.strongMode) {
+      LibraryElementImpl library = getRequiredInput(UNIT_INPUT);
+      List<LibraryElement> component = library.libraryCycle;
+      outputs[LIBRARY_CYCLE] = component;
+      outputs[LIBRARY_CYCLE_UNITS] = component.expand((l) => l.units).toList();
+    } else {
+      outputs[LIBRARY_CYCLE] = [];
+      outputs[LIBRARY_CYCLE_UNITS] = [];
+    }
+  }
+
+  /**
+   * Return a map from the names of the inputs of this kind of task to the task
+   * input descriptors describing those inputs for a task with the
+   * given [target].
+   */
+  static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
+    LibrarySpecificUnit unit = target;
+    return <String, TaskInput>{
+      'resolveReachableLibraries': new _ImportExportSourceClosureTaskInput(

[Leaf, 2015/10/06 00:14:58]

For the most part, this avoids adding additional dependencies over non-strong
mode, but I don't know how to avoid these ones.  The task will return an empty
list in non-strong mode, but by virtue of its input dependencies it will have
forced additional work.  But since I don't access to the context here, I don't
know how to filter these out.  This is responsible for the failing test in
context_test.dart.  Suggestions?

[Brian Wilkerson, 2015/10/06 19:04:46]

Without being able to access the context so that we can determine whether we're
running strong mode: no, I can't think of a good way. I think we'll just have to
see what the performance hit is and decide whether it's worth the effort to fix
it.
It seems like the extra tasks must be doing something differently in the
non-strong-mode case in order to cause different behavior, so that seems like a
bug we need to fix before committing.

Also, would it work to use "IMPORT_EXPORT_SOURCE_CLOSURE.of(unit.library)"
instead of creating the _ImportExportSourceClosureTaskInput directly? This input
will force the closure to be computed even if it has already been computed and
cached.

[Leaf, 2015/10/07 18:53:55]

Replaced with IMPORT_EXPORT_SOURCE_CLOSURE

+          unit.library, LIBRARY_ELEMENT2),
+      UNIT_INPUT: LIBRARY_ELEMENT2.of(unit.library)
+    };
+  }
+
+  /**
+   * Create a [ComputeLibraryCycleTask] based on the
+   * given [target] in the given [context].
+   */
+  static ComputeLibraryCycleTask createTask(
+      AnalysisContext context, AnalysisTarget target) {
+    return new ComputeLibraryCycleTask(context, target);
+  }
+}
+
+/**
  * A base class for analysis tasks whose target is expected to be a
  * [ConstantEvaluationTarget].
  */
 abstract class ConstantEvaluationAnalysisTask extends AnalysisTask {
   /**
    * Initialize a newly created task to perform analysis within the given
    * [context] in order to produce results for the given [constant].
    */
   ConstantEvaluationAnalysisTask(
       AnalysisContext context, ConstantEvaluationTarget constant)
@@ skipping 238 matching lines @@
       AnalysisContext context, AnalysisTarget target) {
     return new DartErrorsTask(context, target);
   }
 }
 
 /**
  * A task that builds [RESOLVED_UNIT] for a unit.
  */
 class EvaluateUnitConstantsTask extends SourceBasedAnalysisTask {
   /**
-   * The name of the [RESOLVED_UNIT8] input.
+   * The name of the [RESOLVED_UNIT9] input.
    */
   static const String UNIT_INPUT = 'UNIT_INPUT';
 
   /**
    * The name of the [CONSTANT_VALUE] input.
    */
   static const String CONSTANT_VALUES = 'CONSTANT_VALUES';
 
   /**
    * The task descriptor describing this kind of task.
@@ skipping 20 matching lines @@
 
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the
    * given [target].
    */
   static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
     LibrarySpecificUnit unit = target;
     return <String, TaskInput>{
       'libraryElement': LIBRARY_ELEMENT.of(unit.library),
-      UNIT_INPUT: RESOLVED_UNIT8.of(unit),
+      UNIT_INPUT: RESOLVED_UNIT9.of(unit),
       CONSTANT_VALUES:
           COMPILATION_UNIT_CONSTANTS.of(unit).toListOf(CONSTANT_VALUE)
     };
   }
 
   /**
    * Create an [EvaluateUnitConstantsTask] based on the given [target] in
    * the given [context].
    */
   static EvaluateUnitConstantsTask createTask(
@@ skipping 103 matching lines @@
     }
     return newNames;
   }
 }
 
 /**
  * A task that builds [USED_IMPORTED_ELEMENTS] for a unit.
  */
 class GatherUsedImportedElementsTask extends SourceBasedAnalysisTask {
   /**
-   * The name of the [RESOLVED_UNIT8] input.
+   * The name of the [RESOLVED_UNIT9] input.
    */
   static const String UNIT_INPUT = 'UNIT_INPUT';
 
   /**
    * The task descriptor describing this kind of task.
    */
   static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
       'GatherUsedImportedElementsTask',
       createTask,
       buildInputs,
@@ skipping 23 matching lines @@
     outputs[USED_IMPORTED_ELEMENTS] = visitor.usedElements;
   }
 
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the
    * given [target].
    */
   static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
     LibrarySpecificUnit unit = target;
-    return <String, TaskInput>{UNIT_INPUT: RESOLVED_UNIT8.of(unit)};
+    return <String, TaskInput>{UNIT_INPUT: RESOLVED_UNIT9.of(unit)};
   }
 
   /**
    * Create a [GatherUsedImportedElementsTask] based on the given [target] in
    * the given [context].
    */
   static GatherUsedImportedElementsTask createTask(
       AnalysisContext context, AnalysisTarget target) {
     return new GatherUsedImportedElementsTask(context, target);
   }
 }
 
 /**
  * A task that builds [USED_LOCAL_ELEMENTS] for a unit.
  */
 class GatherUsedLocalElementsTask extends SourceBasedAnalysisTask {
   /**
-   * The name of the [RESOLVED_UNIT8] input.
+   * The name of the [RESOLVED_UNIT9] input.
    */
   static const String UNIT_INPUT = 'UNIT_INPUT';
 
   /**
    * The task descriptor describing this kind of task.
    */
   static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
       'GatherUsedLocalElementsTask',
       createTask,
       buildInputs,
@@ skipping 23 matching lines @@
     outputs[USED_LOCAL_ELEMENTS] = visitor.usedElements;
   }
 
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the
    * given [target].
    */
   static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
     LibrarySpecificUnit unit = target;
-    return <String, TaskInput>{UNIT_INPUT: RESOLVED_UNIT8.of(unit)};
+    return <String, TaskInput>{UNIT_INPUT: RESOLVED_UNIT9.of(unit)};
   }
 
   /**
    * Create a [GatherUsedLocalElementsTask] based on the given [target] in
    * the given [context].
    */
   static GatherUsedLocalElementsTask createTask(
       AnalysisContext context, AnalysisTarget target) {
     return new GatherUsedLocalElementsTask(context, target);
   }
 }
 
 /**
  * A task that generates [HINTS] for a unit.
  */
 class GenerateHintsTask extends SourceBasedAnalysisTask {
   /**
-   * The name of the [RESOLVED_UNIT8] input.
+   * The name of the [RESOLVED_UNIT9] input.
    */
   static const String RESOLVED_UNIT_INPUT = 'RESOLVED_UNIT';
 
   /**
    * The name of a list of [USED_LOCAL_ELEMENTS] for each library unit input.
    */
   static const String USED_LOCAL_ELEMENTS_INPUT = 'USED_LOCAL_ELEMENTS';
 
   /**
    * The name of a list of [USED_IMPORTED_ELEMENTS] for each library unit input.
@@ skipping 130 matching lines @@
    */
   static const String UNIT_INPUT = 'UNIT_INPUT';
 
   /**
    * The task descriptor describing this kind of task.
    */
   static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
       'InferInstanceMembersInUnitTask',
       createTask,
       buildInputs,
-      <ResultDescriptor>[RESOLVED_UNIT7]);
+      <ResultDescriptor>[RESOLVED_UNIT8]);
 
   /**
    * Initialize a newly created task to build a library element for the given
    * [unit] in the given [context].
    */
   InferInstanceMembersInUnitTask(
       InternalAnalysisContext context, LibrarySpecificUnit unit)
       : super(context, unit);
 
   @override
@@ skipping 10 matching lines @@
     // Infer instance members.
     //
     if (context.analysisOptions.strongMode) {
       InstanceMemberInferrer inferrer = new InstanceMemberInferrer(typeProvider,
           typeSystem: context.typeSystem);
       inferrer.inferCompilationUnit(unit.element);
     }
     //
     // Record outputs.
     //
-    outputs[RESOLVED_UNIT7] = unit;
+    outputs[RESOLVED_UNIT8] = unit;
   }
 
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the given
    * [libSource].
    */
   static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
     LibrarySpecificUnit unit = target;
     return <String, TaskInput>{
-      UNIT_INPUT: RESOLVED_UNIT6.of(unit),
-      TYPE_PROVIDER_INPUT: TYPE_PROVIDER.of(AnalysisContextTarget.request)
+      UNIT_INPUT: RESOLVED_UNIT7.of(unit),
+      TYPE_PROVIDER_INPUT: TYPE_PROVIDER.of(AnalysisContextTarget.request),
+      // In strong mode, add additional dependencies to enforce inference
+      // ordering.
+
+      // Require that field re-resolution be complete for all units in the
+      // current library cycle.
+      'orderLibraryCycleTasks': LIBRARY_CYCLE_UNITS.of(unit).toList(
+          (CompilationUnitElementImpl unit) => RESOLVED_UNIT7
+              .of(new LibrarySpecificUnit(unit.librarySource, unit.source))),
+      // Require that full inference be complete for all dependencies of the
+      // current library cycle.
+      'orderLibraryCycles': LIBRARY_CYCLE_DEPENDENCIES.of(unit).toList(

[Leaf, 2015/10/06 00:14:58]

This dependency is actually always satisfied since RESOLVED_UNIT7.of(unit)
transitively requires the same dependency.  Is it considered "good style" in the
task model to rely on these implicit transitive dependencies, or better to make
them explicit?

[Brian Wilkerson, 2015/10/06 19:04:46]

I think it's better to make the dependencies explicit. That way if the
computation of a RESOLVED_UNIT7 can be optimized and that dependency removed we
don't end up breaking this task.

[Leaf, 2015/10/07 18:53:55]

Acknowledged.

+          (CompilationUnitElementImpl unit) => RESOLVED_UNIT8
+              .of(new LibrarySpecificUnit(unit.librarySource, unit.source)))
     };
   }
 
   /**
    * Create a [InferInstanceMembersInUnitTask] based on the given [target] in
    * the given [context].
    */
   static InferInstanceMembersInUnitTask createTask(
       AnalysisContext context, AnalysisTarget target) {
     return new InferInstanceMembersInUnitTask(context, target);
   }
 }
 
 /**
+ * A task that ensures that all of the inferrable instance members in a
+ * compilation unit have had their right hand sides re-resolved
+ */
+class ResolveInstanceFieldsInUnitTask extends SourceBasedAnalysisTask {
+  /**
+   * The name of the [TYPE_PROVIDER] input.
+   */
+  static const String TYPE_PROVIDER_INPUT = 'TYPE_PROVIDER_INPUT';
+
+  /**
+   * The name of the input whose value is the [RESOLVED_UNIT6] for the
+   * compilation unit.
+   */
+  static const String UNIT_INPUT = 'UNIT_INPUT';
+
+  /**
+   * The task descriptor describing this kind of task.
+   */
+  static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
+      'ResolveInstanceFieldsInUnitTask',
+      createTask,
+      buildInputs,
+      <ResultDescriptor>[RESOLVED_UNIT7]);
+
+  /**
+   * Initialize a newly created task to build a library element for the given
+   * [unit] in the given [context].
+   */
+  ResolveInstanceFieldsInUnitTask(
+      InternalAnalysisContext context, LibrarySpecificUnit unit)
+      : super(context, unit);
+
+  @override
+  TaskDescriptor get descriptor => DESCRIPTOR;
+
+  @override
+  void internalPerform() {
+    //
+    // Prepare inputs.
+    //
+    CompilationUnit unit = getRequiredInput(UNIT_INPUT);
+    TypeProvider typeProvider = getRequiredInput(TYPE_PROVIDER_INPUT);
+    if (context.analysisOptions.strongMode) {
+      //
+      // Resolve instance fields.
+      //
+      CompilationUnitElement unitElement = unit.element;
+      RecordingErrorListener errorListener = new RecordingErrorListener();
+      for (CompilationUnitMember unitMember in unit.declarations) {
+        if (unitMember is ClassDeclaration) {
+          for (ClassMember member in unitMember.members) {
+            if (member is FieldDeclaration &&
+                !(member.fields.isConst || member.isStatic)) {
+              member.fields.variables.forEach((v) => _resolveVariable(
+                  v, unitElement, typeProvider, errorListener));
+            }
+          }
+        }
+      }
+    }
+    //
+    // Record outputs.
+    //
+    outputs[RESOLVED_UNIT7] = unit;
+  }
+
+  void _resolveVariable(
+      VariableDeclaration variable,
+      CompilationUnitElement unitElement,
+      TypeProvider typeProvider,
+      RecordingErrorListener errorListener) {
+    //    ResolutionEraser.erase(variable, eraseDeclarations: false);
+    ResolutionContext resolutionContext =
+        ResolutionContextBuilder.contextFor(variable, errorListener);
+    ResolverVisitor visitor = new ResolverVisitor(
+        unitElement.library, unitElement.source, typeProvider, errorListener,
+        nameScope: resolutionContext.scope);
+    if (resolutionContext.enclosingClassDeclaration != null) {
+      visitor.prepareToResolveMembersInClass(
+          resolutionContext.enclosingClassDeclaration);
+    }
+    visitor.initForIncrementalResolution(variable);
+    variable.accept(visitor);
+  }
+
+  /**
+   * Return a map from the names of the inputs of this kind of task to the task
+   * input descriptors describing those inputs for a task with the given
+   * [libSource].
+   */
+  static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
+    LibrarySpecificUnit unit = target;
+    return <String, TaskInput>{
+      UNIT_INPUT: RESOLVED_UNIT6.of(unit),
+      TYPE_PROVIDER_INPUT: TYPE_PROVIDER.of(AnalysisContextTarget.request),
+      // In strong mode, add additional dependencies to enforce inference
+      // ordering.
+
+      // Require that static variable inference  be complete for all units in
+      // the current library cycle.
+      'orderLibraryCycleTasks': LIBRARY_CYCLE_UNITS.of(unit).toList(
+          (CompilationUnitElementImpl unit) => RESOLVED_UNIT6
+              .of(new LibrarySpecificUnit(unit.librarySource, unit.source))),
+      // Require that full inference be complete for all dependencies of the
+      // current library cycle.
+      'orderLibraryCycles': LIBRARY_CYCLE_DEPENDENCIES.of(unit).toList(
+          (CompilationUnitElementImpl unit) => RESOLVED_UNIT8
+              .of(new LibrarySpecificUnit(unit.librarySource, unit.source)))
+    };
+  }
+
+  /**
+   * Create a [ResolveInstanceFieldsInUnitTask] based on the given [target] in
+   * the given [context].
+   */
+  static ResolveInstanceFieldsInUnitTask createTask(
+      AnalysisContext context, AnalysisTarget target) {
+    return new ResolveInstanceFieldsInUnitTask(context, target);
+  }
+}
+
+/**
  * An abstract class that defines utility methods that are useful for tasks
  * operating on static variables.
  */
 abstract class InferStaticVariableTask extends ConstantEvaluationAnalysisTask {
   InferStaticVariableTask(
       InternalAnalysisContext context, VariableElement variable)
       : super(context, variable);
 
   /**
    * Return the declaration of the target within the given compilation [unit].
@@ skipping 24 matching lines @@
    */
   static const String UNIT_INPUT = 'UNIT_INPUT';
 
   /**
    * The name of the input whose value is a list of the inferrable static
    * variables whose types have been computed.
    */
   static const String INFERRED_VARIABLES_INPUT = 'INFERRED_VARIABLES_INPUT';
 
   /**
-   * The name of the input whose value is a list of the errors produced while
-   * inferring types for static variables.
-   */
-  static const String INFER_STATIC_VARIABLE_ERRORS_INPUT =
-      'INFER_STATIC_VARIABLE_ERRORS';
-
-  /**
    * The task descriptor describing this kind of task.
    */
   static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
       'InferStaticVariableTypesInUnitTask',
       createTask,
       buildInputs,
-      <ResultDescriptor>[INFER_STATIC_VARIABLE_TYPES_ERRORS, RESOLVED_UNIT6]);
+      <ResultDescriptor>[RESOLVED_UNIT6]);
 
   /**
    * Initialize a newly created task to build a library element for the given
    * [unit] in the given [context].
    */
   InferStaticVariableTypesInUnitTask(
       InternalAnalysisContext context, LibrarySpecificUnit unit)
       : super(context, unit);
 
   @override
   TaskDescriptor get descriptor => DESCRIPTOR;
 
   @override
   void internalPerform() {
     //
     // Prepare inputs.
     //
     CompilationUnit unit = getRequiredInput(UNIT_INPUT);
-    List<List<AnalysisError>> perVariableErrors =
-        getRequiredInput(INFER_STATIC_VARIABLE_ERRORS_INPUT);
-    List<AnalysisError> errors = <AnalysisError>[];
-    for (List<AnalysisError> variableErrors in perVariableErrors) {
-      errors.addAll(variableErrors);
-    }
     //
     // Record outputs. There is no additional work to be done at this time
     // because the work has implicitly been done by virtue of the task model
     // preparing all of the inputs.
     //
-    outputs[INFER_STATIC_VARIABLE_TYPES_ERRORS] = errors;
     outputs[RESOLVED_UNIT6] = unit;
   }
 
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the given
    * [libSource].
    */
   static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
     LibrarySpecificUnit unit = target;
     return <String, TaskInput>{
       INFERRED_VARIABLES_INPUT: INFERABLE_STATIC_VARIABLES_IN_UNIT
           .of(unit)
           .toListOf(INFERRED_STATIC_VARIABLE),
-      INFER_STATIC_VARIABLE_ERRORS_INPUT: INFERABLE_STATIC_VARIABLES_IN_UNIT
-          .of(unit)
-          .toListOf(INFER_STATIC_VARIABLE_ERRORS),
       UNIT_INPUT: RESOLVED_UNIT5.of(unit)
     };
   }
 
   /**
    * Create a [InferStaticVariableTypesInUnitTask] based on the given [target]
    * in the given [context].
    */
   static InferStaticVariableTypesInUnitTask createTask(
       AnalysisContext context, AnalysisTarget target) {
@@ skipping 18 matching lines @@
   static const String TYPE_PROVIDER_INPUT = 'TYPE_PROVIDER_INPUT';
 
   /**
    * The name of the [RESOLVED_UNIT5] input.
    */
   static const String UNIT_INPUT = 'UNIT_INPUT';
 
   static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
       'InferStaticVariableTypeTask',
       createTask,
-      buildInputs, <ResultDescriptor>[
-    INFER_STATIC_VARIABLE_ERRORS,
-    INFERRED_STATIC_VARIABLE
-  ]);
+      buildInputs,
+      <ResultDescriptor>[INFERRED_STATIC_VARIABLE]);
 
   InferStaticVariableTypeTask(
       InternalAnalysisContext context, VariableElement variable)
       : super(context, variable);
 
   @override
   TaskDescriptor get descriptor => DESCRIPTOR;
 
   @override
   bool get handlesDependencyCycles => true;
 
   @override
   void internalPerform() {
     //
     // Prepare inputs.
     //
     // Note: DEPENDENCIES_INPUT is not needed.  It is merely a bookkeeping
     // dependency to ensure that the variables that this variable references
     // have types inferred before inferring the type of this variable.
     //
     VariableElementImpl variable = target;
 
     CompilationUnit unit = getRequiredInput(UNIT_INPUT);
     TypeProvider typeProvider = getRequiredInput(TYPE_PROVIDER_INPUT);
     RecordingErrorListener errorListener = new RecordingErrorListener();
-    VariableDeclaration declaration = getDeclaration(unit);
-    //
-    // Re-resolve the variable's initializer so that the inferred types of other
-    // variables will be propagated.
-    //
-    Expression initializer = declaration.initializer;
-    ResolutionEraser.erase(initializer, eraseDeclarations: false);
-    ResolutionContext resolutionContext =
-        ResolutionContextBuilder.contextFor(initializer, errorListener);
-    ResolverVisitor visitor = new ResolverVisitor(
-        variable.library, variable.source, typeProvider, errorListener,
-        nameScope: resolutionContext.scope);
-    if (resolutionContext.enclosingClassDeclaration != null) {
-      visitor.prepareToResolveMembersInClass(
-          resolutionContext.enclosingClassDeclaration);
-    }
-    visitor.initForIncrementalResolution();
-    initializer.accept(visitor);
 
     // If we're not in a dependency cycle, and we have no type annotation,
-    // do inference.
+    // re-resolve the right hand side and do inference.
     if (dependencyCycle == null && variable.hasImplicitType) {
+      VariableDeclaration declaration = getDeclaration(unit);
+      //
+      // Re-resolve the variable's initializer so that the inferred types of other
+      // variables will be propagated.
+      //
+      Expression initializer = declaration.initializer;
+      ResolutionContext resolutionContext =
+          ResolutionContextBuilder.contextFor(initializer, errorListener);
+      ResolverVisitor visitor = new ResolverVisitor(
+          variable.library, variable.source, typeProvider, errorListener,
+          nameScope: resolutionContext.scope);
+      if (resolutionContext.enclosingClassDeclaration != null) {
+        visitor.prepareToResolveMembersInClass(
+            resolutionContext.enclosingClassDeclaration);
+      }
+      visitor.initForIncrementalResolution();
+      initializer.accept(visitor);
+
       //
       // Record the type of the variable.
       //
       DartType newType = initializer.staticType;
       if (newType == null || newType.isBottom) {
         newType = typeProvider.dynamicType;
       }
       variable.type = newType;
       (variable.initializer as ExecutableElementImpl).returnType = newType;
       if (variable is PropertyInducingElementImpl) {
         setReturnType(variable.getter, newType);
         if (!variable.isFinal && !variable.isConst) {
           setParameterType(variable.setter, newType);
         }
       }
     } else {
       // TODO(brianwilkerson) For now we simply don't infer any type for
       // variables or fields involved in a cycle. We could try to be smarter
       // by re-resolving the initializer in a context in which the types of all
       // of the variables in the cycle are assumed to be `null`, but it isn't
       // clear to me that this would produce better results often enough to
       // warrant the extra effort.
     }
     //
     // Record outputs.
     //
     outputs[INFERRED_STATIC_VARIABLE] = variable;
-    outputs[INFER_STATIC_VARIABLE_ERRORS] = errorListener.errors;
   }
 
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the given
    * [target].
    */
   static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
     VariableElement variable = target;
     LibrarySpecificUnit unit =
         new LibrarySpecificUnit(variable.library.source, variable.source);
     return <String, TaskInput>{
       DEPENDENCIES_INPUT: INFERABLE_STATIC_VARIABLE_DEPENDENCIES
           .of(variable)
           .toListOf(INFERRED_STATIC_VARIABLE),
       TYPE_PROVIDER_INPUT: TYPE_PROVIDER.of(AnalysisContextTarget.request),
-      UNIT_INPUT: RESOLVED_UNIT5.of(unit)
+      UNIT_INPUT: RESOLVED_UNIT5.of(unit),
+      // In strong mode, add additional dependencies to enforce inference
+      // ordering.
+
+      // Require that full inference be complete for all dependencies of the
+      // current library cycle.
+      'orderLibraryCycles': LIBRARY_CYCLE_DEPENDENCIES.of(unit).toList(
+          (CompilationUnitElementImpl unit) => RESOLVED_UNIT8
+              .of(new LibrarySpecificUnit(unit.librarySource, unit.source)))
     };
   }
 
   /**
    * Create a [InferStaticVariableTypeTask] based on the given [target] in the
    * given [context].
    */
   static InferStaticVariableTypeTask createTask(
       AnalysisContext context, AnalysisTarget target) {
     return new InferStaticVariableTypeTask(context, target);
@@ skipping 61 matching lines @@
    * The name of the [BUILD_LIBRARY_ERRORS] input.
    */
   static const String BUILD_LIBRARY_ERRORS_INPUT = 'BUILD_LIBRARY_ERRORS';
 
   /**
    * The name of the [HINTS] input.
    */
   static const String HINTS_INPUT = 'HINTS';
 
   /**
-   * The name of the [INFER_STATIC_VARIABLE_TYPES_ERRORS] input.
+   * The name of the [RESOLVE_UNIT_ERRORS] input.
    */
-  static const String INFER_STATIC_VARIABLE_TYPES_ERRORS_INPUT =
-      'INFER_STATIC_VARIABLE_TYPES_ERRORS';
-
-  /**
-   * The name of the [PARTIALLY_RESOLVE_REFERENCES_ERRORS] input.
-   */
-  static const String PARTIALLY_RESOLVE_REFERENCES_ERRORS_INPUT =
-      'PARTIALLY_RESOLVE_REFERENCES_ERRORS';
-
-  /**
-   * The name of the [RESOLVE_FUNCTION_BODIES_ERRORS] input.
-   */
-  static const String RESOLVE_FUNCTION_BODIES_ERRORS_INPUT =
-      'RESOLVE_FUNCTION_BODIES_ERRORS';
+  static const String RESOLVE_UNIT_ERRORS_INPUT = 'RESOLVE_UNIT_ERRORS';
 
   /**
    * The name of the [RESOLVE_TYPE_NAMES_ERRORS] input.
    */
   static const String RESOLVE_TYPE_NAMES_ERRORS_INPUT =
       'RESOLVE_TYPE_NAMES_ERRORS';
 
   /**
    * The name of the [VARIABLE_REFERENCE_ERRORS] input.
    */
@@ skipping 22 matching lines @@
 
   @override
   void internalPerform() {
     //
     // Prepare inputs.
     //
     List<List<AnalysisError>> errorLists = <List<AnalysisError>>[];
     errorLists.add(getRequiredInput(BUILD_DIRECTIVES_ERRORS_INPUT));
     errorLists.add(getRequiredInput(BUILD_LIBRARY_ERRORS_INPUT));
     errorLists.add(getRequiredInput(HINTS_INPUT));
-    errorLists.add(getRequiredInput(INFER_STATIC_VARIABLE_TYPES_ERRORS_INPUT));
-    errorLists.add(getRequiredInput(PARTIALLY_RESOLVE_REFERENCES_ERRORS_INPUT));
-    errorLists.add(getRequiredInput(RESOLVE_FUNCTION_BODIES_ERRORS_INPUT));
+    errorLists.add(getRequiredInput(RESOLVE_UNIT_ERRORS_INPUT));
     errorLists.add(getRequiredInput(RESOLVE_TYPE_NAMES_ERRORS_INPUT));
     errorLists.add(getRequiredInput(VARIABLE_REFERENCE_ERRORS_INPUT));
     errorLists.add(getRequiredInput(VERIFY_ERRORS_INPUT));
     //
     // Record outputs.
     //
     outputs[LIBRARY_UNIT_ERRORS] = AnalysisError.mergeLists(errorLists);
   }
 
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the
    * given [unit].
    */
   static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
     LibrarySpecificUnit unit = target;
     Map<String, TaskInput> inputs = <String, TaskInput>{
       HINTS_INPUT: HINTS.of(unit),
-      INFER_STATIC_VARIABLE_TYPES_ERRORS_INPUT:
-          INFER_STATIC_VARIABLE_TYPES_ERRORS.of(unit),
-      PARTIALLY_RESOLVE_REFERENCES_ERRORS_INPUT:
-          PARTIALLY_RESOLVE_REFERENCES_ERRORS.of(unit),
-      RESOLVE_FUNCTION_BODIES_ERRORS_INPUT:
-          RESOLVE_FUNCTION_BODIES_ERRORS.of(unit),
+      RESOLVE_UNIT_ERRORS_INPUT: RESOLVE_UNIT_ERRORS.of(unit),
       RESOLVE_TYPE_NAMES_ERRORS_INPUT: RESOLVE_TYPE_NAMES_ERRORS.of(unit),
       VARIABLE_REFERENCE_ERRORS_INPUT: VARIABLE_REFERENCE_ERRORS.of(unit),
       VERIFY_ERRORS_INPUT: VERIFY_ERRORS.of(unit)
     };
     Source source = unit.source;
     if (unit.library == source) {
       inputs[BUILD_DIRECTIVES_ERRORS_INPUT] =
           BUILD_DIRECTIVES_ERRORS.of(source);
       inputs[BUILD_LIBRARY_ERRORS_INPUT] = BUILD_LIBRARY_ERRORS.of(source);
     } else {
@@ skipping 221 matching lines @@
    * The name of the [TYPE_PROVIDER] input.
    */
   static const String TYPE_PROVIDER_INPUT = 'TYPE_PROVIDER_INPUT';
 
   /**
    * The task descriptor describing this kind of task.
    */
   static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
       'PartiallyResolveUnitReferencesTask',
       createTask,
-      buildInputs, <ResultDescriptor>[
-    INFERABLE_STATIC_VARIABLES_IN_UNIT,
-    PARTIALLY_RESOLVE_REFERENCES_ERRORS,
-    RESOLVED_UNIT5
-  ]);
+      buildInputs,
+      <ResultDescriptor>[INFERABLE_STATIC_VARIABLES_IN_UNIT, RESOLVED_UNIT5]);
 
   PartiallyResolveUnitReferencesTask(
       InternalAnalysisContext context, AnalysisTarget target)
       : super(context, target);
 
   @override
   TaskDescriptor get descriptor => DESCRIPTOR;
 
   @override
   void internalPerform() {
@@ skipping 11 matching lines @@
     InheritanceManager inheritanceManager =
         new InheritanceManager(libraryElement);
     PartialResolverVisitor visitor = new PartialResolverVisitor(
         libraryElement, unitElement.source, typeProvider, errorListener,
         inheritanceManager: inheritanceManager);
     unit.accept(visitor);
     //
     // Record outputs.
     //
     outputs[INFERABLE_STATIC_VARIABLES_IN_UNIT] = visitor.variablesAndFields;
-    outputs[PARTIALLY_RESOLVE_REFERENCES_ERRORS] =
-        removeDuplicateErrors(errorListener.errors);
     outputs[RESOLVED_UNIT5] = unit;
   }
 
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the
    * given [target].
    */
   static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
     LibrarySpecificUnit unit = target;
     return <String, TaskInput>{
       'fullyBuiltLibraryElements': IMPORT_EXPORT_SOURCE_CLOSURE
           .of(unit.library)
           .toListOf(LIBRARY_ELEMENT5),
       LIBRARY_INPUT: LIBRARY_ELEMENT5.of(unit.library),
       UNIT_INPUT: RESOLVED_UNIT4.of(unit),
-      TYPE_PROVIDER_INPUT: TYPE_PROVIDER.of(AnalysisContextTarget.request)
+      TYPE_PROVIDER_INPUT: TYPE_PROVIDER.of(AnalysisContextTarget.request),
+      // In strong mode, add additional dependencies to enforce inference
+      // ordering.
+
+      // Require that full inference be complete for all dependencies of the
+      // current library cycle.
+      'orderLibraryCycles': LIBRARY_CYCLE_DEPENDENCIES.of(unit).toList(
+          (CompilationUnitElementImpl unit) => RESOLVED_UNIT8
+              .of(new LibrarySpecificUnit(unit.librarySource, unit.source)))
     };
   }
 
   /**
    * Create a [PartiallyResolveUnitReferencesTask] based on the given [target]
    * in the given [context].
    */
   static PartiallyResolveUnitReferencesTask createTask(
       AnalysisContext context, AnalysisTarget target) {
     return new PartiallyResolveUnitReferencesTask(context, target);
@@ skipping 134 matching lines @@
         dependsOn.add(name);
       }
     }
   }
 }
 
 /**
  * A task that resolves the bodies of top-level functions, constructors, and
  * methods within a single compilation unit.
  */
-class ResolveFunctionBodiesInUnitTask extends SourceBasedAnalysisTask {
+class ResolveUnitTask extends SourceBasedAnalysisTask {
+  /**
+   * The name of the input whose value is the defining [LIBRARY_ELEMENT5].
+   */
+  static const String LIBRARY_INPUT = 'LIBRARY_INPUT';
+
   /**
    * The name of the [TYPE_PROVIDER] input.
    */
   static const String TYPE_PROVIDER_INPUT = 'TYPE_PROVIDER_INPUT';
 
   /**
-   * The name of the [RESOLVED_UNIT7] input.
+   * The name of the [RESOLVED_UNIT8] input.
    */
   static const String UNIT_INPUT = 'UNIT_INPUT';
 
   static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
-      'ResolveFunctionBodiesInUnitTask',
+      'ResolveUnitTask',
       createTask,
       buildInputs,
-      <ResultDescriptor>[RESOLVE_FUNCTION_BODIES_ERRORS, RESOLVED_UNIT8]);
+      <ResultDescriptor>[RESOLVE_UNIT_ERRORS, RESOLVED_UNIT9]);
 
-  ResolveFunctionBodiesInUnitTask(
+  ResolveUnitTask(
       InternalAnalysisContext context, LibrarySpecificUnit compilationUnit)
       : super(context, compilationUnit);
 
   @override
   TaskDescriptor get descriptor => DESCRIPTOR;
 
   @override
   void internalPerform() {
     //
     // Prepare inputs.
     //
+    LibraryElement libraryElement = getRequiredInput(LIBRARY_INPUT);
     CompilationUnit unit = getRequiredInput(UNIT_INPUT);
     TypeProvider typeProvider = getRequiredInput(TYPE_PROVIDER_INPUT);
     //
-    // Resolve function bodies.
+    // Resolve everything
     //
     CompilationUnitElement unitElement = unit.element;
     RecordingErrorListener errorListener = new RecordingErrorListener();
-    for (CompilationUnitMember unitMember in unit.declarations) {
-      if (unitMember is FunctionDeclaration) {
-        _resolveFunctionBody(unitMember.functionExpression.body, unitElement,
-            typeProvider, errorListener);
-      } else if (unitMember is ClassDeclaration) {
-        for (ClassMember classMember in unitMember.members) {
-          if (classMember is ConstructorDeclaration) {
-            _resolveFunctionBody(
-                classMember.body, unitElement, typeProvider, errorListener);
-          } else if (classMember is MethodDeclaration) {
-            _resolveFunctionBody(
-                classMember.body, unitElement, typeProvider, errorListener);
-          }
-        }
-      }
-    }
+    ResolverVisitor visitor = new ResolverVisitor(
+        libraryElement, unitElement.source, typeProvider, errorListener);
+    unit.accept(visitor);
     //
     // Record outputs.
     //
-    outputs[RESOLVE_FUNCTION_BODIES_ERRORS] = errorListener.errors;
-    outputs[RESOLVED_UNIT8] = unit;
-  }
-
-  void _resolveFunctionBody(
-      FunctionBody functionBody,
-      CompilationUnitElement unitElement,
-      TypeProvider typeProvider,
-      RecordingErrorListener errorListener) {
-    ResolutionContext resolutionContext =
-        ResolutionContextBuilder.contextFor(functionBody, errorListener);
-    ResolverVisitor visitor = new ResolverVisitor(
-        unitElement.library, unitElement.source, typeProvider, errorListener,
-        nameScope: resolutionContext.scope);
-    if (resolutionContext.enclosingClassDeclaration != null) {
-      visitor.prepareToResolveMembersInClass(
-          resolutionContext.enclosingClassDeclaration);
-    }
-    Declaration declaration = functionBody.getAncestor((AstNode node) =>
-        node is ConstructorDeclaration ||
-            node is FunctionDeclaration ||
-            node is MethodDeclaration);
-    visitor.initForIncrementalResolution(declaration);
-    functionBody.accept(visitor);
-    if (declaration is FunctionDeclaration) {
-      // This is in the wrong place. The propagated return type is stored
-      // locally in the resolver, not in the declaration (or element). Hence,
-      // this needs to happen later.
-      declaration.accept(visitor.typeAnalyzer);
-    }
+    outputs[RESOLVE_UNIT_ERRORS] = errorListener.errors;
+    outputs[RESOLVED_UNIT9] = unit;
   }
 
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the given
    * [target].
    */
   static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
     LibrarySpecificUnit unit = target;
     return <String, TaskInput>{
+      LIBRARY_INPUT: LIBRARY_ELEMENT5.of(unit.library),
       TYPE_PROVIDER_INPUT: TYPE_PROVIDER.of(AnalysisContextTarget.request),
-      UNIT_INPUT: RESOLVED_UNIT7.of(unit)
+      UNIT_INPUT: RESOLVED_UNIT8.of(unit),
+      // In strong mode, add additional dependencies to enforce inference
+      // ordering.
+
+      // Require that inference be complete for all units in the
+      // current library cycle.
+      'orderLibraryCycleTasks': LIBRARY_CYCLE_UNITS.of(unit).toList(
+          (CompilationUnitElementImpl unit) => RESOLVED_UNIT8
+              .of(new LibrarySpecificUnit(unit.librarySource, unit.source)))
     };
   }
 
   /**
-   * Create a [ResolveFunctionBodiesInUnitTask] based on the given [target] in
+   * Create a [ResolveUnitTask] based on the given [target] in
    * the given [context].
    */
-  static ResolveFunctionBodiesInUnitTask createTask(
+  static ResolveUnitTask createTask(
       AnalysisContext context, AnalysisTarget target) {
-    return new ResolveFunctionBodiesInUnitTask(context, target);
+    return new ResolveUnitTask(context, target);
   }
 }
 
 /**
  * A task that finishes resolution by requesting [RESOLVED_UNIT_NO_CONSTANTS] for every
  * unit in the libraries closure and produces [LIBRARY_ELEMENT].
  */
 class ResolveLibraryReferencesTask extends SourceBasedAnalysisTask {
   /**
    * The name of the [LIBRARY_ELEMENT5] input.
    */
   static const String LIBRARY_INPUT = 'LIBRARY_INPUT';
 
   /**
-   * The name of the list of [RESOLVED_UNIT8] input.
+   * The name of the list of [RESOLVED_UNIT9] input.
    */
   static const String UNITS_INPUT = 'UNITS_INPUT';
 
   /**
    * The task descriptor describing this kind of task.
    */
   static final TaskDescriptor DESCRIPTOR = new TaskDescriptor(
       'ResolveLibraryReferencesTask',
       createTask,
       buildInputs,
@@ skipping 28 matching lines @@
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the
    * given [target].
    */
   static Map<String, TaskInput> buildInputs(AnalysisTarget target) {
     Source source = target;
     return <String, TaskInput>{
       LIBRARY_INPUT: LIBRARY_ELEMENT5.of(source),
       UNITS_INPUT: UNITS.of(source).toList((Source unit) =>
-          RESOLVED_UNIT8.of(new LibrarySpecificUnit(source, unit))),
+          RESOLVED_UNIT9.of(new LibrarySpecificUnit(source, unit))),
       'resolvedUnits': IMPORT_EXPORT_SOURCE_CLOSURE
           .of(source)
           .toMapOf(UNITS)
           .toFlattenList((Source library, Source unit) =>
-              RESOLVED_UNIT8.of(new LibrarySpecificUnit(library, unit))),
+              RESOLVED_UNIT9.of(new LibrarySpecificUnit(library, unit))),
     };
   }
 
   /**
    * Create a [ResolveLibraryReferencesTask] based on the given [target] in
    * the given [context].
    */
   static ResolveLibraryReferencesTask createTask(
       AnalysisContext context, AnalysisTarget target) {
     return new ResolveLibraryReferencesTask(context, target);
@@ skipping 583 matching lines @@
 
   @override
   bool moveNext() {
     if (_newSources.isEmpty) {
       return false;
     }
     currentTarget = _newSources.removeLast();
     return true;
   }
 }