Completions with exact prefix should be prioritized - fixes #23099

[email protected]

Review URL: https://codereview.chromium.org//1369033002 .

Author: danrubel

pkg/analysis_server/lib/src/services/completion/local_reference_contributor.dart

@@ -351,9 +351,20 @@ class _LabelVisitor extends LocalDeclarationVisitor {
 class _LocalVisitor extends LocalDeclarationVisitor {
   final DartCompletionRequest request;
   final OpType optype;
+  int privateMemberRelevance = DART_RELEVANCE_DEFAULT;
 
   _LocalVisitor(this.request, int offset, this.optype) : super(offset) {
     includeLocalInheritedTypes = !optype.inStaticMethodBody;
+    if (request.replacementLength > 0) {
+      var contents = request.source.contents;
+      if (contents != null &&
+          contents.data != null &&
+          contents.data.startsWith('_', request.replacementOffset)) {
+        // If user typed identifier starting with '_'
+        // then do not suppress the relevance of private members
+        privateMemberRelevance = null;
+      }
+    }
   }
 
   @override
@@ -554,6 +565,10 @@ class _LocalVisitor extends LocalDeclarationVisitor {
         id, isDeprecated, relevance, typeName,
         classDecl: classDecl);
     if (suggestion != null) {
+      if (privateMemberRelevance != null &&
+          suggestion.completion.startsWith('_')) {
+        suggestion.relevance = privateMemberRelevance;
+      }
       request.addSuggestion(suggestion);
       suggestion.element = createElement(request.source, elemKind, id,
           isAbstract: isAbstract,

pkg/analysis_server/test/services/completion/completion_test_util.dart

@@ -1357,7 +1357,8 @@ abstract class AbstractSelectorSuggestionTest extends AbstractCompletionTest {
       //assertSuggestImportedTopLevelVar('T3', 'int', COMPLETION_RELEVANCE_LOW);
       assertNotSuggested('_T4');
       assertSuggestLocalTopLevelVar('T5', 'int');
-      assertSuggestLocalTopLevelVar('_T6', null);
+      assertSuggestLocalTopLevelVar('_T6', null,
+          relevance: DART_RELEVANCE_DEFAULT);
       assertNotSuggested('==');
       assertSuggestLocalGetter('T7', 'String');
       assertSuggestLocalSetter('T8');
@@ -3473,7 +3474,8 @@ abstract class AbstractSelectorSuggestionTest extends AbstractCompletionTest {
         expect(getterF.element.isDeprecated, isTrue);
         expect(getterF.element.isPrivate, isFalse);
       }
-      CompletionSuggestion getterG = assertSuggestLocalGetter('_g', null);
+      CompletionSuggestion getterG = assertSuggestLocalGetter('_g', null,
+          relevance: DART_RELEVANCE_DEFAULT);
       if (getterG != null) {
         expect(getterG.element.isDeprecated, isFalse);
         expect(getterG.element.isPrivate, isTrue);
@@ -3528,7 +3530,8 @@ abstract class AbstractSelectorSuggestionTest extends AbstractCompletionTest {
     return computeFull((bool result) {
       expect(request.replacementOffset, completionOffset);
       expect(request.replacementLength, 0);
-      CompletionSuggestion methodA = assertSuggestLocalMethod('_a', 'A', 'Z');
+      CompletionSuggestion methodA = assertSuggestLocalMethod('_a', 'A', 'Z',
+          relevance: DART_RELEVANCE_DEFAULT);
       if (methodA != null) {
         expect(methodA.element.isDeprecated, isFalse);
         expect(methodA.element.isPrivate, isTrue);

pkg/analysis_server/test/services/completion/local_reference_contributor_test.dart

@@ -793,6 +793,20 @@ class B extends A {m() {^}}
     assertSuggestMethod('m', 'B', null, relevance: DART_RELEVANCE_LOCAL_METHOD);
   }
 
+  test_prioritization_private() {
+    addTestSource('main() {var ab; var _ab; _^}');
+    expect(computeFast(), isTrue);
+    assertSuggestLocalVariable('ab', null);
+    assertSuggestLocalVariable('_ab', null);
+  }
+
+  test_prioritization_public() {
+    addTestSource('main() {var ab; var _ab; a^}');
+    expect(computeFast(), isTrue);
+    assertSuggestLocalVariable('ab', null);
+    assertSuggestLocalVariable('_ab', null, relevance: DART_RELEVANCE_DEFAULT);
+  }
+
   test_shadowed_name() {
     addTestSource('var a; class A { var a; m() { ^ } }');
     expect(computeFast(), isTrue);