Replace isAppropriateFor with suitabilityFor and start using it

pkg/analyzer/lib/task/model.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.task.model;
 
 import 'dart:collection';
 import 'dart:developer';
 
 import 'package:analyzer/src/generated/engine.dart' hide AnalysisTask;
@@ skipping 19 matching lines @@
 /**
  * A function that takes the target for which a task will produce results and
  * returns a map from input names to descriptions of the analysis results needed
  * by the task in order for the task to be performed. Such functions are passed
  * to a [TaskDescriptor] to be used to determine the inputs needed by the task.
  */
 typedef Map<String, TaskInput> CreateTaskInputs(AnalysisTarget target);
 
 /**
  * A function that takes the target for which a task will produce results and
- * returns `true` if the task is appropriate for the target. Such functions are
- * passed to a [TaskDescriptor] to be used to determine the inputs needed by the
- * task.
+ * returns an indication of how suitable the task is for the target. Such
+ * functions are passed to a [TaskDescriptor] to be used to determine their
+ * suitability for computing results.
  */
-typedef bool IsAppropriateFor(AnalysisTarget target);
+typedef TaskSuitability SuitabilityFor(AnalysisTarget target);
 
 /**
  * A function that converts an object of the type [B] into a [TaskInput].
  * This is used, for example, by a [ListTaskInput] to create task inputs
  * for each value in a list of values.
  */
 typedef TaskInput<E> UnaryFunction<B, E>(B object);
 
 /**
  * An [AnalysisTarget] wrapper for an [AnalysisContext].
@@ skipping 475 matching lines @@
   /**
    * Initialize a newly created task descriptor to have the given [name] and to
    * describe a task that takes the inputs built using the given [inputBuilder],
    * and produces the given [results]. The [buildTask] function will be used to
    * create the instance of [AnalysisTask] being described. If provided, the
    * [isAppropriateFor] function will be used to determine whether the task can
    * be used on a specific target.
    */
   factory TaskDescriptor(String name, BuildTask buildTask,
       CreateTaskInputs inputBuilder, List<ResultDescriptor> results,
-      {IsAppropriateFor isAppropriateFor}) = TaskDescriptorImpl;
+      {SuitabilityFor suitabilityFor}) = TaskDescriptorImpl;
 
   /**
    * Return the builder used to build the inputs to the task.
    */
   CreateTaskInputs get createTaskInputs;
 
   /**
    * Return the name of the task being described.
    */
   String get name;
 
   /**
    * Return a list of the analysis results that will be computed by this task.
    */
   List<ResultDescriptor> get results;
 
   /**
    * Create and return a task that is described by this descriptor that can be
    * used to compute results based on the given [inputs].
    */
   AnalysisTask createTask(AnalysisContext context, AnalysisTarget target,
       Map<String, dynamic> inputs);
 
   /**
-   * Return `true` if this task is appropriate for the given [target].
+   * Return an indication of how suitable this task is for the given [target].
    */
-  bool isAppropriateFor(AnalysisTarget target);
+  TaskSuitability suitabilityFor(AnalysisTarget target);
 }
 
 /**
  * A description of an input to an [AnalysisTask] that can be used to compute
  * that input.
  *
  * Clients may not extend, implement or mix-in this class.
  */
 abstract class TaskInput<V> {
   /**
@@ skipping 78 matching lines @@
    * It is safe to invoke [moveNext] after it has returned `false`. In this case
    * [moveNext] has no effect and will again return `false`.
    *
    * Throws a [StateError] if the value of the current result has not been
    * provided using [currentValue].
    */
   bool moveNext();
 }
 
 /**
+ * An indication of how suitable a task is for a given target.
+ */
+enum TaskSuitability { NONE, LOWEST, HIGHEST }
+
+/**
  * [WorkManager]s are used to drive analysis.
  *
  * They know specific of the targets and results they care about,
  * so they can request analysis results in optimal order.
  *
  * Clients may implement this class when implementing plugins.
  */
 abstract class WorkManager {
   /**
    * Notifies the manager about changes in the explicit source list.
@@ skipping 72 matching lines @@
   /**
    * A work should be done, but without any special urgency.
    */
   NORMAL,
 
   /**
    * Nothing to do.
    */
   NONE
 }