Use offset/length of the import prefix, or empty. Same for constructor names.

R=brianwilkerson@google.com

Bug: https://github.com/dart-lang/sdk/issues/32685
Change-Id: I40b7f9c679b04725db19dad661e3a88a4a982f1c
Reviewed-on: https://dart-review.googlesource.com/48682
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

pkg/analysis_server/doc/api.html

@@ -4797,7 +4797,7 @@ a:focus, a:hover {
         
         <p>
           The offset to the beginning of the name selected to be
-          renamed.
+          renamed, or -1 if the name does not exist yet.
         </p>
       </dd><dt class="field"><b>length: int</b></dt><dd>
         

pkg/analysis_server/lib/protocol/protocol_generated.dart

@@ -14330,12 +14330,14 @@ class RenameFeedback extends RefactoringFeedback {
   String _oldName;
 
   /**
-   * The offset to the beginning of the name selected to be renamed.
+   * The offset to the beginning of the name selected to be renamed, or -1 if
+   * the name does not exist yet.
    */
   int get offset => _offset;
 
   /**
-   * The offset to the beginning of the name selected to be renamed.
+   * The offset to the beginning of the name selected to be renamed, or -1 if
+   * the name does not exist yet.
    */
   void set offset(int value) {
     assert(value != null);

pkg/analysis_server/lib/src/edit/edit_domain.dart

@@ -939,20 +939,44 @@ class _RefactoringManager {
       AstNode node = await server.getNodeAtOffset(file, offset);
       Element element = server.getElementOfNode(node);
       if (node != null && element != null) {
+        int feedbackOffset = node.offset;
+        int feedbackLength = node.length;
+
         if (element is FieldFormalParameterElement) {
           element = (element as FieldFormalParameterElement).field;
         }
-        // climb from "Class" in "new Class.named()" to "Class.named"
-        if (node.parent is TypeName && node.parent.parent is ConstructorName) {
-          ConstructorName constructor = node.parent.parent;
-          node = constructor;
-          element = constructor.staticElement;
+
+        // Use the prefix offset/length when renaming an import directive.
+        if (node is ImportDirective && element is ImportElement) {
+          if (node.prefix != null) {
+            feedbackOffset = node.prefix.offset;
+            feedbackLength = node.prefix.length;
+          } else {
+            feedbackOffset = -1;
+            feedbackLength = 0;
+          }
         }
+
+        // Canonicalize to ConstructorName.
+        var constructorName = _canonicalizeToConstructorName(node);
+        if (constructorName != null) {
+          node = constructorName;
+          element = constructorName.staticElement;
+          // Use the constructor name offset/length.
+          if (constructorName.name != null) {
+            feedbackOffset = constructorName.name.offset;
+            feedbackLength = constructorName.name.length;
+          } else {
+            feedbackOffset = -1;
+            feedbackLength = 0;
+          }
+        }
+
         // do create the refactoring
         refactoring = new RenameRefactoring(
             searchEngine, server.getAstProvider(file), element);
-        feedback =
-            new RenameFeedback(node.offset, node.length, 'kind', 'oldName');
+        feedback = new RenameFeedback(
+            feedbackOffset, feedbackLength, 'kind', 'oldName');
       }
     }
     if (refactoring == null) {
@@ -1087,6 +1111,32 @@ class _RefactoringManager {
     }
     return new RefactoringStatus();
   }
+
+  /**
+   * If the [node] is a constructor reference, return the corresponding
+   * [ConstructorName], or `null` otherwise.
+   */
+  static ConstructorName _canonicalizeToConstructorName(AstNode node) {
+    var parent = node.parent;
+    var parent2 = parent?.parent;
+
+    // "named" in "Class.named".
+    if (parent is ConstructorName) {
+      return parent;
+    }
+
+    // "Class" in "Class.named".
+    if (parent is TypeName && parent2 is ConstructorName) {
+      return parent2;
+    }
+
+    // Canonicalize "new Class.named()" to "Class.named".
+    if (node is InstanceCreationExpression) {
+      return node.constructorName;
+    }
+
+    return null;
+  }
 }
 
 /**

pkg/analysis_server/test/edit/refactoring_test.dart

@@ -1562,16 +1562,24 @@ class B {
   B() {}
 }
 ''');
-    return assertSuccessfulRefactoring(() {
-      return sendRenameRequest('B;', 'newName');
-    }, '''
+    return assertSuccessfulRefactoring(
+      () {
+        return sendRenameRequest('B;', 'newName');
+      },
+      '''
 class A {
   A() = B.newName;
 }
 class B {
   B.newName() {}
 }
-''');
+''',
+      feedbackValidator: (feedback) {
+        RenameFeedback renameFeedback = feedback;
+        expect(renameFeedback.offset, -1);
+        expect(renameFeedback.length, 0);
+      },
+    );
   }
 
   test_constructor_fromInstanceCreation() {
@@ -1583,16 +1591,24 @@ main() {
   new A.test();
 }
 ''');
-    return assertSuccessfulRefactoring(() {
-      return sendRenameRequest('test();', 'newName');
-    }, '''
+    return assertSuccessfulRefactoring(
+      () {
+        return sendRenameRequest('test();', 'newName');
+      },
+      '''
 class A {
   A.newName() {}
 }
 main() {
   new A.newName();
 }
-''');
+''',
+      feedbackValidator: (feedback) {
+        RenameFeedback renameFeedback = feedback;
+        expect(renameFeedback.offset, 43);
+        expect(renameFeedback.length, 4);
+      },
+    );
   }
 
   test_constructor_fromInstanceCreation_default_onClassName() {
@@ -1604,16 +1620,24 @@ main() {
   new A();
 }
 ''');
-    return assertSuccessfulRefactoring(() {
-      return sendRenameRequest('A();', 'newName');
-    }, '''
+    return assertSuccessfulRefactoring(
+      () {
+        return sendRenameRequest('A();', 'newName');
+      },
+      '''
 class A {
   A.newName() {}
 }
 main() {
   new A.newName();
 }
-''');
+''',
+      feedbackValidator: (feedback) {
+        RenameFeedback renameFeedback = feedback;
+        expect(renameFeedback.offset, -1);
+        expect(renameFeedback.length, 0);
+      },
+    );
   }
 
   test_constructor_fromInstanceCreation_default_onNew() {
@@ -1625,16 +1649,24 @@ main() {
   new A();
 }
 ''');
-    return assertSuccessfulRefactoring(() {
-      return sendRenameRequest('new A();', 'newName');
-    }, '''
+    return assertSuccessfulRefactoring(
+      () {
+        return sendRenameRequest('new A();', 'newName');
+      },
+      '''
 class A {
   A.newName() {}
 }
 main() {
   new A.newName();
 }
-''');
+''',
+      feedbackValidator: (feedback) {
+        RenameFeedback renameFeedback = feedback;
+        expect(renameFeedback.offset, -1);
+        expect(renameFeedback.length, 0);
+      },
+    );
   }
 
   test_feedback() {
@@ -1682,16 +1714,23 @@ main() {
   Future f;
 }
 ''');
-    return assertSuccessfulRefactoring(() {
-      return sendRenameRequest("import 'dart:async';", 'new_name');
-    }, '''
+    return assertSuccessfulRefactoring(
+        () {
+          return sendRenameRequest("import 'dart:async';", 'new_name');
+        },
+        '''
 import 'dart:math';
 import 'dart:async' as new_name;
 main() {
   Random r;
   new_name.Future f;
 }
-''');
+''',
+        feedbackValidator: (feedback) {
+          RenameFeedback renameFeedback = feedback;
+          expect(renameFeedback.offset, -1);
+          expect(renameFeedback.length, 0);
+        });
   }
 
   test_importPrefix_remove() {
@@ -1703,16 +1742,23 @@ main() {
   test.Future f;
 }
 ''');
-    return assertSuccessfulRefactoring(() {
-      return sendRenameRequest("import 'dart:async' as test;", '');
-    }, '''
+    return assertSuccessfulRefactoring(
+        () {
+          return sendRenameRequest("import 'dart:async' as test;", '');
+        },
+        '''
 import 'dart:math' as test;
 import 'dart:async';
 main() {
   test.Random r;
   Future f;
 }
-''');
+''',
+        feedbackValidator: (feedback) {
+          RenameFeedback renameFeedback = feedback;
+          expect(renameFeedback.offset, 51);
+          expect(renameFeedback.length, 4);
+        });
   }
 
   test_init_fatalError_noElement() {
@@ -1970,9 +2016,13 @@ class _AbstractGetRefactoring_Test extends AbstractAnalysisTest {
   }
 
   Future assertSuccessfulRefactoring(
-      Future<Response> requestSender(), String expectedCode) async {
+      Future<Response> requestSender(), String expectedCode,
+      {void Function(RefactoringFeedback) feedbackValidator}) async {
     EditGetRefactoringResult result = await getRefactoringResult(requestSender);
     assertResultProblemsOK(result);
+    if (feedbackValidator != null) {
+      feedbackValidator(result.feedback);
+    }
     assertTestRefactoringResult(result, expectedCode);
   }
 

pkg/analysis_server/tool/spec/generated/java/types/RenameFeedback.java

@@ -34,7 +34,8 @@ public class RenameFeedback extends RefactoringFeedback {
   public static final List<RenameFeedback> EMPTY_LIST = Lists.newArrayList();
 
   /**
-   * The offset to the beginning of the name selected to be renamed.
+   * The offset to the beginning of the name selected to be renamed, or -1 if the name does not exist
+   * yet.
    */
   private final int offset;
 
@@ -113,7 +114,8 @@ public class RenameFeedback extends RefactoringFeedback {
   }
 
   /**
-   * The offset to the beginning of the name selected to be renamed.
+   * The offset to the beginning of the name selected to be renamed, or -1 if the name does not exist
+   * yet.
    */
   public int getOffset() {
     return offset;

pkg/analysis_server/tool/spec/spec_input.html

@@ -4382,7 +4382,7 @@
         <ref>int</ref>
         <p>
           The offset to the beginning of the name selected to be
-          renamed.
+          renamed, or -1 if the name does not exist yet.
         </p>
       </field>
       <field name="length">