Issue 29288. Resynthesize Import/Export/PartElement for every directive.

pkg/analyzer/lib/src/summary/resynthesize.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 summary_resynthesizer;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/standard_ast_factory.dart';
@@ skipping 195 matching lines @@
         libraryElement.exportNamespace = new Namespace({});
         return libraryElement;
       }
       UnlinkedUnit unlinkedSummary = getUnlinkedSummary(uri);
       if (unlinkedSummary == null) {
         throw new StateError('Unable to find unlinked summary: $uri');
       }
       List<UnlinkedUnit> serializedUnits = <UnlinkedUnit>[unlinkedSummary];
       for (String part in serializedUnits[0].publicNamespace.parts) {
         Source partSource = sourceFactory.resolveUri(librarySource, part);
-        if (partSource == null) {
-          serializedUnits.add(null);
-        } else {
+        UnlinkedUnit partUnlinkedUnit;
+        if (partSource != null) {
           String partAbsUri = partSource.uri.toString();
-          serializedUnits.add(getUnlinkedSummary(partAbsUri) ??
-              new UnlinkedUnitBuilder(codeRange: new CodeRangeBuilder()));
+          partUnlinkedUnit = getUnlinkedSummary(partAbsUri);
         }
+        serializedUnits.add(partUnlinkedUnit ??
+            new UnlinkedUnitBuilder(codeRange: new CodeRangeBuilder()));
       }
       _LibraryResynthesizer libraryResynthesizer = new _LibraryResynthesizer(
           this, serializedLibrary, serializedUnits, librarySource);
       LibraryElement library = libraryResynthesizer.buildLibrary();
       _resynthesizedUnits[uri] = libraryResynthesizer.resynthesizedUnits;
       return library;
     });
   }
 
   /**
@@ skipping 797 matching lines @@
   }
 
   /**
    * Create a [_UnitResynthesizer] that will resynthesize the part with the
    * given [uri]. Return `null` if the [uri] is invalid.
    */
   _UnitResynthesizer buildPart(_UnitResynthesizer definingUnitResynthesizer,
       String uri, UnlinkedPart partDecl, int unitNum) {
     Source unitSource =
         summaryResynthesizer.sourceFactory.resolveUri(librarySource, uri);
-    if (unitSource == null) {
-      return null;
-    }
     _UnitResynthesizer partResynthesizer =
         createUnitResynthesizer(unitNum, unitSource, partDecl);
     CompilationUnitElementImpl partUnit = partResynthesizer.unit;
     partUnit.uriOffset = partDecl.uriOffset;
     partUnit.uriEnd = partDecl.uriEnd;
     partUnit.source = unitSource;
     partUnit.librarySource = librarySource;
     partUnit.uri = uri;
     return partResynthesizer;
   }
@@ skipping 41 matching lines @@
       partUri = partSource.uri.toString();
     } else {
       partUri = referencedLibraryUri;
     }
     return <String>[referencedLibraryUri, partUri, name];
   }
 
   /**
    * Remember the absolute URI to the corresponding unit mapping.
    */
-  void rememberUriToUnit(_UnitResynthesizer unitResynthesized) {
-    CompilationUnitElementImpl unit = unitResynthesized.unit;
-    String absoluteUri = unit.source.uri.toString();
-    resynthesizedUnits[absoluteUri] = unit;
+  void rememberUriToUnit(_UnitResynthesizer unitResynthesizer) {
+    CompilationUnitElementImpl unit = unitResynthesizer.unit;
+    Source source = unit.source;
+    if (source != null) {
+      String absoluteUri = source.uri.toString();
+      resynthesizedUnits[absoluteUri] = unit;
+    }
   }
 }
 
 /**
  * Implementation of [LibraryResynthesizerContext] for [_LibraryResynthesizer].
  */
 class _LibraryResynthesizerContext implements LibraryResynthesizerContext {
   final _LibraryResynthesizer resynthesizer;
 
   _LibraryResynthesizerContext(this.resynthesizer);
@@ skipping 387 matching lines @@
   ResynthesizerContext _resynthesizerContext;
 
   _UnitResynthesizer(this.libraryResynthesizer, this.unlinkedUnit,
       this.linkedUnit, Source unitSource, UnlinkedPart unlinkedPart) {
     _resynthesizerContext = new _ResynthesizerContext(this);
     unit = new CompilationUnitElementImpl.forSerialized(
         libraryResynthesizer.library,
         _resynthesizerContext,
         unlinkedUnit,
         unlinkedPart,
-        unitSource.shortName);
+        unitSource?.shortName);
 
     {
       List<int> lineStarts = unlinkedUnit.lineStarts;
       if (lineStarts.isEmpty) {
         lineStarts = const <int>[0];
       }
       unit.lineInfo = new LineInfo(lineStarts);
     }
 
     for (EntityRef t in linkedUnit.types) {
@@ skipping 436 matching lines @@
   static String _getElementIdentifier(String name, ReferenceKind kind) {
     if (kind == ReferenceKind.topLevelPropertyAccessor ||
         kind == ReferenceKind.propertyAccessor) {
       if (!name.endsWith('=')) {
         return name + '?';
       }
     }
     return name;
   }
 }