partition imported/not-imported suggestion sets / de-dup

Change-Id: Iba72b3599e9153e9fac3dd883d7bdb272c25fa65
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/135622
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Phil Quitslund <pquitslund@google.com>

pkg/analysis_server/test/client/completion_driver_test.dart

@@ -227,6 +227,51 @@ class CompletionWithSuggestionsTest extends AbstractCompletionDriverTest {
   @override
   String get testFilePath => '$projectPath/lib/test.dart';
 
+  Future<void> test_project_filterImports() async {
+    await addProjectFile('lib/a.dart', r'''
+class A {}
+''');
+
+    await addProjectFile('lib/b.dart', r'''
+export 'a.dart';
+''');
+
+    await addTestFile('''
+import 'a.dart';
+void main() {
+  ^
+}
+''');
+
+    expectSuggestion(
+        completion: 'A',
+        element: ElementKind.CONSTRUCTOR,
+        kind: CompletionSuggestionKind.INVOCATION);
+  }
+
+  Future<void> test_project_filterMultipleImports() async {
+    await addProjectFile('lib/a.dart', r'''
+class A {}
+''');
+
+    await addProjectFile('lib/b.dart', r'''
+export 'a.dart';
+''');
+
+    await addTestFile('''
+import 'a.dart';
+import 'b.dart';
+void main() {
+  ^
+}
+''');
+
+    expectSuggestion(
+        completion: 'A',
+        element: ElementKind.CLASS,
+        kind: CompletionSuggestionKind.INVOCATION);
+  }
+
   Future<void> test_project_lib() async {
     await addProjectFile('lib/a.dart', r'''
 class A {}
@@ -278,6 +323,28 @@ void main() {
   }
 
   @failingTest
+  Future<void> test_project_lib_multipleExports() async {
+    await addProjectFile('lib/a.dart', r'''
+class A {}
+''');
+
+    await addProjectFile('lib/b.dart', r'''
+export 'a.dart';
+''');
+
+    await addTestFile('''
+void main() {
+  ^
+}
+''');
+
+    // Should only have one suggestion.
+    expectSuggestion(
+        completion: 'A',
+        element: ElementKind.CONSTRUCTOR,
+        kind: CompletionSuggestionKind.INVOCATION);
+  }
+
   Future<void> test_sdk_lib_future_isNotDuplicated() async {
     await addTestFile('''
 void main() {

pkg/analysis_server/test/client/impl/completion_driver.dart

@@ -150,6 +150,10 @@ class CompletionDriver extends AbstractClient with ExpectMixin {
       allSuggestions[id] = params.results;
       var includedKinds = params.includedElementKinds;
 
+      //
+      // Collect relevance information.
+      //
+
       // https://github.com/JetBrains/intellij-plugins/blob/59018828753973324ea0500fa4bae93563f1aacf/Dart/src/com/jetbrains/lang/dart/analyzer/DartAnalysisServerService.java#L467
       var includedRelevanceTags = <String, IncludedSuggestionRelevanceTag>{};
       var includedSuggestionRelevanceTags =
@@ -161,22 +165,79 @@ class CompletionDriver extends AbstractClient with ExpectMixin {
         }
       }
 
+      //
+      // Identify imported libraries.
+      //
+
+      var importedLibraryUris = <String>{};
+      var existingImports = fileToExistingImports[params.libraryFile];
+      if (existingImports != null) {
+        for (var existingImport in existingImports.imports) {
+          var uri = existingImports.elements.strings[existingImport.uri];
+          importedLibraryUris.add(uri);
+        }
+      }
+
+      //
+      // Partition included suggestion sets into imported and not-imported groups.
+      //
+
+      var importedSets = <IncludedSuggestionSet>[];
+      var notImportedSets = <IncludedSuggestionSet>[];
+
       for (var set in params.includedSuggestionSets) {
         var id = set.id;
         while (!idToSetMap.containsKey(id)) {
           await Future.delayed(const Duration(milliseconds: 1));
         }
         var suggestionSet = idToSetMap[id];
-        for (var suggestion in suggestionSet.items) {
-          var kind = suggestion.element.kind;
-          if (!includedKinds.contains(kind)) {
-            continue;
-          }
+        if (importedLibraryUris.contains(suggestionSet.uri)) {
+          importedSets.add(set);
+        } else {
+          notImportedSets.add(set);
+        }
+      }
 
-          var completionSuggestion =
-              _createCompletionSuggestionFromAvailableSuggestion(
-                  suggestion, set.relevance, includedRelevanceTags);
-          suggestions.add(completionSuggestion);
+      //
+      // Add suggestions.
+      //
+      // First from imported then from not-imported sets.
+      //
+
+      void addSuggestion(
+          AvailableSuggestion suggestion, IncludedSuggestionSet includeSet) {
+        var kind = suggestion.element.kind;
+        if (!includedKinds.contains(kind)) {
+          return;
+        }
+        var completionSuggestion =
+            _createCompletionSuggestionFromAvailableSuggestion(
+                suggestion, includeSet.relevance, includedRelevanceTags);
+        suggestions.add(completionSuggestion);
+      }
+
+      // Track seen elements to ensure they are not duplicated.
+      var seenElements = <String>{};
+
+      // Suggestions can be uniquely identified by kind, label and uri.
+      String suggestionId(AvailableSuggestion s) =>
+          '${s.declaringLibraryUri}:${s.element.kind}:${s.label}';
+
+      for (var includeSet in importedSets) {
+        var set = idToSetMap[includeSet.id];
+        for (var suggestion in set.items) {
+          if (seenElements.add(suggestionId(suggestion))) {
+            addSuggestion(suggestion, includeSet);
+          }
+        }
+      }
+
+      for (var includeSet in notImportedSets) {
+        var set = idToSetMap[includeSet.id];
+        for (var suggestion in set.items) {
+          if (!seenElements.contains(suggestionId(suggestion))) {
+            addSuggestion(suggestion, includeSet);
+          }
         }
       }