Handle redirected constructors when generating summaries from ASTs.

pkg/analyzer/lib/src/summary/link.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.
 
 /**
  * This library is capable of producing linked summaries from unlinked
  * ones (or prelinked ones).  It functions by building a miniature
  * element model to represent the contents of the summaries, and then
  * scanning the element model to gather linked information and adding
  * it to the summary data structures.
@@ skipping 136 matching lines @@
    */
   bool get isObject;
 
   @override
   String get name;
 
   @override
   ConstructorElementForLink get unnamedConstructor;
 
   @override
-  ReferenceableElementForLink getContainedName(name) {
+  ReferenceableElementForLink getContainedName(String name) {
     if (_containedNames == null) {
       _containedNames = <String, ReferenceableElementForLink>{};
       // TODO(paulberry): what's the correct way to handle name conflicts?
       for (ConstructorElementForLink constructor in constructors) {
         _containedNames[constructor.name] = constructor;
       }
       for (FieldElementForLink field in fields) {
         // TODO(paulberry): do we need to handle nonstatic fields for
         // consistent behavior with erroneous code?
         if (field.isStatic) {
@@ skipping 435 matching lines @@
     void safeAddDependency(ConstNode target) {
       if (target != null) {
         dependencies.add(target);
       }
     }
     UnlinkedExecutable unlinkedExecutable =
         constructorElement._unlinkedExecutable;
     ClassElementForLink_Class enclosingClass =
         constructorElement.enclosingElement;
     ConstructorElementForLink redirectedConstructor =
-        _getConstRedirectedConstructor();
+        _getFactoryRedirectedConstructor();
     if (redirectedConstructor != null) {
       if (redirectedConstructor._constNode != null) {
         safeAddDependency(redirectedConstructor._constNode);
       }
     } else if (unlinkedExecutable.isFactory) {
       // Factory constructor, but getConstRedirectedConstructor returned
       // null.  This can happen if we're visiting one of the special external
       // const factory constructors in the SDK, or if the code contains
       // errors (such as delegating to a non-const constructor, or delegating
       // to a constructor that can't be resolved).  In any of these cases,
       // we'll evaluate calls to this constructor without having to refer to
       // any other constants.  So we don't need to report any dependencies.
     } else {
       ClassElementForLink superClass = enclosingClass.supertype?.element;
-      bool superInvocationFound = false;
+      bool defaultSuperInvocationNeeded = true;
       for (UnlinkedConstructorInitializer constructorInitializer
           in constructorElement._unlinkedExecutable.constantInitializers) {
         if (constructorInitializer.kind ==
             UnlinkedConstructorInitializerKind.superInvocation) {
-          superInvocationFound = true;
+          defaultSuperInvocationNeeded = false;
           if (superClass != null && !superClass.isObject) {
             ConstructorElementForLink constructor = superClass
                 .getContainedName(constructorInitializer.name)
                 .asConstructor;
             safeAddDependency(constructor?._constNode);
           }
+        } else if (constructorInitializer.kind ==
+            UnlinkedConstructorInitializerKind.thisInvocation) {
+          defaultSuperInvocationNeeded = false;
+          ConstructorElementForLink constructor = constructorElement
+              .enclosingElement
+              .getContainedName(constructorInitializer.name)
+              .asConstructor;
+          safeAddDependency(constructor?._constNode);
         }
         CompilationUnitElementForLink compilationUnit =
             constructorElement.enclosingElement.enclosingElement;
         collectDependencies(
             dependencies, constructorInitializer.expression, compilationUnit);
         constructorInitializer.arguments.map((UnlinkedConst unlinkedConst) =>
             collectDependencies(dependencies, unlinkedConst, compilationUnit));
       }
 
-      if (!superInvocationFound) {
+      if (defaultSuperInvocationNeeded) {
         // No explicit superconstructor invocation found, so we need to
         // manually insert a reference to the implicit superconstructor.
         if (superClass != null && !superClass.isObject) {
           ConstructorElementForLink unnamedConstructor =
               superClass.unnamedConstructor;
           safeAddDependency(unnamedConstructor?._constNode);
         }
       }
       for (FieldElementForLink field in enclosingClass.fields) {
         // Note: non-static const isn't allowed but we handle it anyway so
         // that we won't be confused by incorrect code.
         if ((field.isFinal || field.isConst) && !field.isStatic) {
           safeAddDependency(field.asConstVariable);
         }
       }
       for (ParameterElementForLink parameterElement
           in constructorElement.parameters) {
         safeAddDependency(parameterElement._constNode);
       }
     }
     return dependencies;
   }
 
   /**
-   * If [constructorElement] redirects to another constructor, return
-   * the constructor it redirects to.
+   * If [constructorElement] redirects to another constructor via a factory
+   * redirect, return the constructor it redirects to.
    */
-  ConstructorElementForLink _getConstRedirectedConstructor() {
-    // TODO(paulberry): implement
-    return null;
+  ConstructorElementForLink _getFactoryRedirectedConstructor() {
+    EntityRef redirectedConstructor =
+        constructorElement._unlinkedExecutable.redirectedConstructor;
+    if (redirectedConstructor != null) {
+      return constructorElement.enclosingElement.enclosingElement
+          ._resolveRef(redirectedConstructor.reference)
+          .asConstructor;
+    } else {
+      return null;
+    }
   }
 }
 
 /**
  * Specialization of [DependencyWalker] for detecting constant
  * evaluation cycles.
  */
 class ConstDependencyWalker extends DependencyWalker<ConstNode> {
   @override
   void evaluate(ConstNode v) {
@@ skipping 148 matching lines @@
     }
     return _parameters;
   }
 
   @override
   DartTypeForLink buildType(DartTypeForLink getTypeArgument(int i),
           List<int> implicitFunctionTypeIndices) =>
       DynamicTypeForLink.instance;
 
   @override
-  ReferenceableElementForLink getContainedName(name) =>
+  ReferenceableElementForLink getContainedName(String name) =>
       UndefinedElementForLink.instance;
 
   /**
    * Perform const cycle detection on this constructor.
    */
   void link(LinkedUnitBuilder linkedUnit) {
     if (_constNode != null && !isCycleFree) {
       linkedUnit.constCycles.add(_unlinkedExecutable.constCycleSlot);
     }
   }
@@ skipping 240 matching lines @@
   @override
   String get name =>
       unlinkedEnumValue == null ? 'values' : unlinkedEnumValue.name;
 
   @override
   DartTypeForLink buildType(DartTypeForLink getTypeArgument(int i),
           List<int> implicitFunctionTypeIndices) =>
       DynamicTypeForLink.instance;
 
   @override
-  ReferenceableElementForLink getContainedName(name) =>
+  ReferenceableElementForLink getContainedName(String name) =>
       UndefinedElementForLink.instance;
 
   @override
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }
 
 /**
  * Representation of an interface type during linking.
  *
  * TODO(paulberry): add the ability to represent type arguments.
@@ skipping 249 matching lines @@
   DartTypeForLink buildType(DartTypeForLink getTypeArgument(int i),
       List<int> implicitFunctionTypeIndices);
 
   /**
    * If this element contains other named elements, return the
    * contained element having the given [name].  If this element can't
    * contain other named elements, or it doesn't contain an element
    * with the given name, return the singleton of
    * [UndefinedElementForLink].
    */
-  ReferenceableElementForLink getContainedName(name);
+  ReferenceableElementForLink getContainedName(String name);
 }
 
 /**
  * Element representing a top level variable resynthesized from a
  * summary during linking.
  */
 class TopLevelVariableElementForLink extends VariableElementForLink
     implements TopLevelVariableElement {
   TopLevelVariableElementForLink(CompilationUnitElement enclosingElement,
       UnlinkedVariable unlinkedVariable)
@@ skipping 36 matching lines @@
 
   @override
   ConstVariableNode get asConstVariable => null;
 
   @override
   DartTypeForLink buildType(DartTypeForLink getTypeArgument(int i),
           List<int> implicitFunctionTypeIndices) =>
       DynamicTypeForLink.instance;
 
   @override
-  ReferenceableElementForLink getContainedName(name) => this;
+  ReferenceableElementForLink getContainedName(String name) => this;
 }
 
 /**
  * Element representing a top level variable resynthesized from a
  * summary during linking.
  */
 class VariableElementForLink
     implements VariableElement, ReferenceableElementForLink {
   /**
    * The unlinked representation of the variable in the summary.
@@ skipping 34 matching lines @@
   bool get isStatic;
 
   @override
   String get name => unlinkedVariable.name;
 
   @override
   DartTypeForLink buildType(DartTypeForLink getTypeArgument(int i),
           List<int> implicitFunctionTypeIndices) =>
       DynamicTypeForLink.instance;
 
-  ReferenceableElementForLink getContainedName(name) {
+  ReferenceableElementForLink getContainedName(String name) {
     // TODO(paulberry): implement.
     // TODO(paulberry): make sure that circularities involving
     // ".length" are handled correctly.
     return UndefinedElementForLink.instance;
   }
 
   @override
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }
 
@@ skipping 85 matching lines @@
 
   /**
    * Throw away any information produced by a previous call to [link].
    */
   void unlink() {
     for (LibraryElementInBuildUnit library in _librariesInBuildUnit) {
       library.unlink();
     }
   }
 }