Add a flag for caching all analysis results in the driver.

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

 // Copyright (c) 2016, 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 analyzer.test.driver;
 
 import 'dart:async';
 import 'dart:convert';
 
 import 'package:analyzer/dart/ast/ast.dart';
@@ skipping 21 matching lines @@
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 import 'package:typed_mock/typed_mock.dart';
 
 import '../../../utils.dart';
 import '../../context/mock_sdk.dart';
 import 'base.dart';
 
 main() {
   defineReflectiveSuite(() {
+    defineReflectiveTests(AnalysisDriverSchedulerTest);
     defineReflectiveTests(AnalysisDriverTest);
-    defineReflectiveTests(AnalysisDriverSchedulerTest);
+    defineReflectiveTests(CacheAllAnalysisDriverTest);
   });
 }
 
 /**
  * Returns a [Future] that completes after pumping the event queue [times]
  * times. By default, this should pump the event queue enough times to allow
  * any code to run, as long as it's not waiting on some external event.
  */
 Future pumpEventQueue([int times = 5000]) {
   if (times == 0) return new Future.value();
@@ skipping 2542 matching lines @@
   /**
    * Return the [provider] specific path for the given Posix [path].
    */
   String _p(String path) => provider.convertPath(path);
 
   static String _md5(String content) {
     return hex.encode(md5.convert(UTF8.encode(content)).bytes);
   }
 }
 
+@reflectiveTest
+class CacheAllAnalysisDriverTest extends BaseAnalysisDriverTest {
+  bool get disableChangesAndCacheAllResults => true;
+
+  test_addFile() async {
+    var a = _p('/test/lib/a.dart');
+    var b = _p('/test/lib/b.dart');
+    driver.addFile(a);
+    driver.addFile(b);
+  }
+
+  test_changeFile() async {
+    var path = _p('/test.dart');
+    expect(() {
+      driver.changeFile(path);
+    }, throwsStateError);
+  }
+
+  test_getResult_libraryUnits() async {
+    var lib = _p('/lib.dart');
+    var part1 = _p('/part1.dart');
+    var part2 = _p('/part2.dart');
+
+    provider.newFile(
+        lib,
+        r'''
+library test;
+part 'part1.dart';
+part 'part2.dart';
+''');
+    provider.newFile(part1, 'part of test; class A {}');
+    provider.newFile(part2, 'part of test; class B {}');
+
+    driver.addFile(lib);
+    driver.addFile(part1);
+    driver.addFile(part2);
+
+    // No analyzed libraries initially.
+    expect(driver.test.numOfAnalyzedLibraries, 0);
+
+    AnalysisResult libResult = await driver.getResult(lib);
+    AnalysisResult partResult1 = await driver.getResult(part1);
+    AnalysisResult partResult2 = await driver.getResult(part2);
+
+    // Just one library was analyzed, results for parts are cached.
+    expect(driver.test.numOfAnalyzedLibraries, 1);
+
+    expect(libResult.path, lib);
+    expect(partResult1.path, part1);
+    expect(partResult2.path, part2);
+
+    expect(libResult.unit, isNotNull);
+    expect(partResult1.unit, isNotNull);
+    expect(partResult2.unit, isNotNull);
+
+    // The parts uses the same resynthesized library element.
+    var libLibrary = libResult.unit.element.library;
+    var partLibrary1 = partResult1.unit.element.library;
+    var partLibrary2 = partResult2.unit.element.library;
+    expect(partLibrary1, same(libLibrary));
+    expect(partLibrary2, same(libLibrary));
+  }
+
+  test_getResult_singleFile() async {
+    var path = _p('/test.dart');
+    provider.newFile(path, 'main() {}');
+    driver.addFile(path);
+
+    AnalysisResult result1 = await driver.getResult(path);
+    expect(driver.test.numOfAnalyzedLibraries, 1);
+    var unit1 = result1.unit;
+    var unitElement1 = unit1.element;
+    expect(result1.path, path);
+    expect(unit1, isNotNull);
+    expect(unitElement1, isNotNull);
+
+    AnalysisResult result2 = await driver.getResult(path);
+    expect(driver.test.numOfAnalyzedLibraries, 1);
+    expect(result2.path, path);
+    expect(result2.unit, same(unit1));
+    expect(result2.unit.element, same(unitElement1));
+  }
+
+  test_removeFile() async {
+    var path = _p('/test.dart');
+    expect(() {
+      driver.removeFile(path);
+    }, throwsStateError);
+  }
+
+  String _p(String path) => provider.convertPath(path);
+}
+
 class _SourceMock extends TypedMock implements Source {}