Implement SearchEngine.searchTopLevelDeclarations() for the new driver.

R=brianwilkerson@google.com
BUG=

Review-Url: https://codereview.chromium.org/2572603003 .

pkg/analysis_server/lib/src/services/search/search_engine_internal2.dart

@@ -66,8 +66,24 @@ class SearchEngineImpl2 implements SearchEngine {
 
   @override
   Future<List<SearchMatch>> searchTopLevelDeclarations(String pattern) async {
-    // TODO(scheglov) implement
-    return [];
+    List<SearchMatch> allDeclarations = [];
+    RegExp regExp = new RegExp(pattern);
+    for (AnalysisDriver driver in _drivers) {
+      List<Element> elements = await driver.search.topLevelElements(regExp);
+      for (Element element in elements) {
+        allDeclarations.add(new _SearchMatch(
+            element.source.fullName,
+            element.librarySource,
+            element.source,
+            element.library,
+            element,
+            true,
+            true,
+            MatchKind.DECLARATION,
+            new SourceRange(element.nameOffset, element.nameLength)));
+      }
+    }
+    return allDeclarations;
   }
 
   Future<List<SearchResult>> _searchDirectSubtypes(ClassElement type) async {

pkg/analysis_server/test/services/search/search_engine2_test.dart

@@ -2,6 +2,8 @@
 // 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.
 
+import 'dart:async';
+
 import 'package:analysis_server/src/services/search/search_engine.dart';
 import 'package:analysis_server/src/services/search/search_engine_internal2.dart';
 import 'package:analyzer/dart/element/element.dart';
@@ -138,6 +140,51 @@ T b;
         matches, contains(predicate((SearchMatch m) => m.element.name == 'b')));
   }
 
+  test_searchTopLevelDeclarations() async {
+    var a = _p('/test/a.dart');
+    var b = _p('/test/b.dart');
+
+    provider.newFile(
+        a,
+        '''
+class A {}
+int a;
+''');
+    provider.newFile(
+        b,
+        '''
+class B {}
+get b => 42;
+''');
+
+    var driver1 = _newDriver();
+    var driver2 = _newDriver();
+
+    driver1.addFile(a);
+    driver2.addFile(b);
+
+    while (scheduler.isAnalyzing) {
+      await new Future.delayed(new Duration(milliseconds: 1));
+    }
+
+    var searchEngine = new SearchEngineImpl2([driver1, driver2]);
+    List<SearchMatch> matches =
+        await searchEngine.searchTopLevelDeclarations('.*');
+    expect(matches, hasLength(4));
+
+    void assertHasElement(String name) {
+      expect(
+          matches,
+          contains(predicate((SearchMatch m) =>
+              m.kind == MatchKind.DECLARATION && m.element.name == name)));
+    }
+
+    assertHasElement('A');
+    assertHasElement('a');
+    assertHasElement('B');
+    assertHasElement('b');
+  }
+
   AnalysisDriver _newDriver() => new AnalysisDriver(
       scheduler,
       logger,

pkg/analyzer/lib/src/dart/analysis/search.dart

@@ -91,6 +91,31 @@ class Search {
     return results;
   }
 
+  /**
+   * Returns top-level elements with names matching the given [regExp].
+   */
+  Future<List<Element>> topLevelElements(RegExp regExp) async {
+    List<Element> elements = <Element>[];
+
+    void addElement(Element element) {
+      if (!element.isSynthetic && regExp.hasMatch(element.displayName)) {
+        elements.add(element);
+      }
+    }
+
+    for (FileState file in _driver.fsState.knownFiles) {
+      CompilationUnitElement unitElement =
+          await _driver.getUnitElement(file.path);
+      unitElement.accessors.forEach(addElement);
+      unitElement.enums.forEach(addElement);
+      unitElement.functions.forEach(addElement);
+      unitElement.functionTypeAliases.forEach(addElement);
+      unitElement.topLevelVariables.forEach(addElement);
+      unitElement.types.forEach(addElement);
+    }
+    return elements;
+  }
+
   Future<Null> _addResults(List<SearchResult> results, Element element,
       Map<IndexRelationKind, SearchResultKind> relationToResultKind) async {
     // Prepare the element name.

pkg/analyzer/test/src/dart/analysis/search_test.dart

@@ -528,6 +528,31 @@ main(A<int> a) {
     await _verifyReferences(method, expected);
   }
 
+  test_searchReferences_ParameterElement_named() async {
+    await _resolveTestUnit('''
+foo({p}) {
+  p = 1;
+  p += 2;
+  print(p);
+  p();
+}
+main() {
+  foo(p: 42);
+}
+''');
+    ParameterElement element = _findElement('p');
+    Element fooElement = _findElement('foo');
+    Element mainElement = _findElement('main');
+    var expected = [
+      _expectId(fooElement, SearchResultKind.WRITE, 'p = 1;'),
+      _expectId(fooElement, SearchResultKind.READ_WRITE, 'p += 2;'),
+      _expectId(fooElement, SearchResultKind.READ, 'p);'),
+      _expectId(fooElement, SearchResultKind.INVOCATION, 'p();'),
+      _expectIdQ(mainElement, SearchResultKind.REFERENCE, 'p: 42')
+    ];
+    await _verifyReferences(element, expected);
+  }
+
   test_searchReferences_ParameterElement_ofConstructor() async {
     await _resolveTestUnit('''
 class C {
@@ -627,31 +652,6 @@ main() {
     await _verifyReferences(element, expected);
   }
 
-  test_searchReferences_ParameterElement_named() async {
-    await _resolveTestUnit('''
-foo({p}) {
-  p = 1;
-  p += 2;
-  print(p);
-  p();
-}
-main() {
-  foo(p: 42);
-}
-''');
-    ParameterElement element = _findElement('p');
-    Element fooElement = _findElement('foo');
-    Element mainElement = _findElement('main');
-    var expected = [
-      _expectId(fooElement, SearchResultKind.WRITE, 'p = 1;'),
-      _expectId(fooElement, SearchResultKind.READ_WRITE, 'p += 2;'),
-      _expectId(fooElement, SearchResultKind.READ, 'p);'),
-      _expectId(fooElement, SearchResultKind.INVOCATION, 'p();'),
-      _expectIdQ(mainElement, SearchResultKind.REFERENCE, 'p: 42')
-    ];
-    await _verifyReferences(element, expected);
-  }
-
   test_searchReferences_PrefixElement() async {
     String partCode = r'''
 part of my_lib;
@@ -924,6 +924,25 @@ class C implements T {} // C
     await _verifyReferences(element, expected);
   }
 
+  test_topLevelElements() async {
+    await _resolveTestUnit('''
+class A {} // A
+class B = Object with A;
+typedef C();
+D() {}
+var E = null;
+class NoMatchABCDE {}
+''');
+    Element a = _findElement('A');
+    Element b = _findElement('B');
+    Element c = _findElement('C');
+    Element d = _findElement('D');
+    Element e = _findElement('E');
+    RegExp regExp = new RegExp(r'^[A-E]$');
+    expect(await driver.search.topLevelElements(regExp),
+        unorderedEquals([a, b, c, d, e]));
+  }
+
   ExpectedResult _expectId(
       Element enclosingElement, SearchResultKind kind, String search,
       {int length, bool isResolved: true, bool isQualified: false}) {