Prioritize analysis of files that import the changed file, or have an error or warning.

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

Index: pkg/analyzer/test/src/dart/analysis/driver_test.dart
diff --git a/pkg/analyzer/test/src/dart/analysis/driver_test.dart b/pkg/analyzer/test/src/dart/analysis/driver_test.dart
index 1bff4ea0def4bbe843ae3066eca4bf047826cebb..33551dbe45b2cb6d97eaffe8d57f73a745394bce 100644
--- a/pkg/analyzer/test/src/dart/analysis/driver_test.dart
+++ b/pkg/analyzer/test/src/dart/analysis/driver_test.dart
@@ -97,6 +97,96 @@ class AnalysisDriverSchedulerTest {
     scheduler.start();
   }
 
+  test_priorities_allChangedFirst() async {
+    AnalysisDriver driver1 = newDriver();
+    AnalysisDriver driver2 = newDriver();
+
+    String a = _p('/a.dart');
+    String b = _p('/b.dart');
+    String c = _p('/c.dart');
+    String d = _p('/d.dart');
+    provider.newFile(a, 'class A {}');
+    provider.newFile(b, "import 'a.dart';");
+    provider.newFile(c, 'class C {}');
+    provider.newFile(d, "import 'c.dart';");
+    driver1.addFile(a);
+    driver1.addFile(b);
+    driver2.addFile(c);
+    driver2.addFile(d);
+
+    await scheduler.waitForIdle();
+    allResults.clear();
+
+    provider.updateFile(a, 'class A2 {}');
+    provider.updateFile(c, 'class C2 {}');
+    driver1.changeFile(a);
+    driver1.changeFile(c);
+    driver2.changeFile(a);
+    driver2.changeFile(c);
+
+    await scheduler.waitForIdle();
+    expect(allResults, hasLength(greaterThanOrEqualTo(2)));
+    expect(allResults[0].path, a);
+    expect(allResults[1].path, c);
+  }
+
+  test_priorities_firstChanged_thenImporting() async {
+    AnalysisDriver driver1 = newDriver();
+    AnalysisDriver driver2 = newDriver();
+
+    String a = _p('/a.dart');
+    String b = _p('/b.dart');
+    String c = _p('/c.dart');
+    provider.newFile(a, "import 'c.dart';");
+    provider.newFile(b, 'class B {}');
+    provider.newFile(c, "import 'b.dart';");
+    driver1.addFile(a);
+    driver1.addFile(b);
+    driver2.addFile(c);
+
+    await scheduler.waitForIdle();
+    allResults.clear();
+
+    provider.updateFile(b, 'class B2 {}');
+    driver1.changeFile(b);
+    driver2.changeFile(b);
+
+    await scheduler.waitForIdle();
+    expect(allResults, hasLength(greaterThanOrEqualTo(2)));
+    expect(allResults[0].path, b);
+    expect(allResults[1].path, c);
+  }
+
+  test_priorities_firstChanged_thenWithErrors() async {
+    AnalysisDriver driver1 = newDriver();
+    AnalysisDriver driver2 = newDriver();
+
+    String a = _p('/a.dart');
+    String b = _p('/b.dart');
+    String c = _p('/c.dart');
+    String d = _p('/d.dart');
+    provider.newFile(a, 'class A {}');
+    provider.newFile(b, "export 'a.dart';");
+    provider.newFile(c, "import 'b.dart';");
+    provider.newFile(d, "import 'b.dart'; class D extends X {}");
+    driver1.addFile(a);
+    driver1.addFile(b);
+    driver2.addFile(c);
+    driver2.addFile(d);
+
+    await scheduler.waitForIdle();
+    allResults.clear();
+
+    provider.updateFile(a, 'class A2 {}');
+    driver1.changeFile(a);
+    driver2.changeFile(a);
+
+    await scheduler.waitForIdle();
+    expect(allResults, hasLength(greaterThanOrEqualTo(2)));
+    expect(allResults[0].path, a);
+    expect(allResults[1].path, d);
+  }
+
   test_priorities_getResult_beforePriority() async {
     AnalysisDriver driver1 = newDriver();
     AnalysisDriver driver2 = newDriver();
@@ -2179,6 +2269,113 @@ var A = B;
     allResults.clear();
   }
 
+  test_results_order() async {
+    var a = _p('/test/lib/a.dart');
+    var b = _p('/test/lib/b.dart');
+    var c = _p('/test/lib/c.dart');
+    var d = _p('/test/lib/d.dart');
+    var e = _p('/test/lib/e.dart');
+    var f = _p('/test/lib/f.dart');
+    provider.newFile(
+        a,
+        r'''
+import 'd.dart';
+''');
+    provider.newFile(b, '');
+    provider.newFile(
+        c,
+        r'''
+import 'd.dart';
+''');
+    provider.newFile(
+        d,
+        r'''
+import 'b.dart';
+''');
+    provider.newFile(
+        e,
+        r'''
+export 'b.dart';
+''');
+    provider.newFile(
+        f,
+        r'''
+import 'e.dart';
+class F extends X {}
+''');
+
+    driver.addFile(a);
+    driver.addFile(b);
+    driver.addFile(c);
+    driver.addFile(d);
+    driver.addFile(e);
+    driver.addFile(f);
+    await scheduler.waitForIdle();
+
+    // The file f.dart has an error or warning.
+    // So, its analysis will have higher priority.
+    expect(driver.fsState.getFileForPath(f).hasErrorOrWarning, isTrue);
+
+    allResults.clear();
+
+    // Update a.dart with changing its API signature.
+    provider.updateFile(b, 'class A {}');
+    driver.changeFile(b);
+    await scheduler.waitForIdle();
+
+    List<String> analyzedPaths = allResults.map((r) => r.path).toList();
+
+    // The changed file must be the first.
+    expect(analyzedPaths[0], b);
+
+    // Then the file that imports the changed file.
+    expect(analyzedPaths[1], d);
+
+    // Then the file that has an error (even if it is unrelated).
+    expect(analyzedPaths[2], f);
+  }
+
+  test_results_order_allChangedFirst_thenImports() async {
+    var a = _p('/test/lib/a.dart');
+    var b = _p('/test/lib/b.dart');
+    var c = _p('/test/lib/c.dart');
+    var d = _p('/test/lib/d.dart');
+    var e = _p('/test/lib/e.dart');
+    provider.newFile(a, 'class A {}');
+    provider.newFile(b, 'class B {}');
+    provider.newFile(c, '');
+    provider.newFile(d, "import 'a.dart';");
+    provider.newFile(e, "import 'b.dart';");
+
+    driver.addFile(a);
+    driver.addFile(b);
+    driver.addFile(c);
+    driver.addFile(d);
+    driver.addFile(e);
+    await scheduler.waitForIdle();
+
+    allResults.clear();
+
+    // Change b.dart and then a.dart files.
+    // So, a.dart and b.dart should be analyzed first.
+    // Then d.dart and e.dart because they import a.dart and b.dart files.
+    provider.updateFile(a, 'class A2 {}');
+    provider.updateFile(b, 'class B2 {}');
+    driver.changeFile(b);
+    driver.changeFile(a);
+    await scheduler.waitForIdle();
+
+    List<String> analyzedPaths = allResults.map((r) => r.path).toList();
+
+    // The changed files must be the first.
+    expect(analyzedPaths[0], a);
+    expect(analyzedPaths[1], b);
+
+    // Then the file that imports the changed file.
+    expect(analyzedPaths[2], d);
+    expect(analyzedPaths[3], e);
+  }
+
   test_results_priority() async {
     String content = 'int f() => 42;';
     addTestFile(content, priority: true);