fix exception and improve keyword completion

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

 // Copyright (c) 2014, 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 test.services.completion.dart.keyword;
 
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analysis_server/src/services/completion/dart_completion_manager.dart';
 import 'package:analysis_server/src/services/completion/keyword_computer.dart';
 import 'package:analyzer/src/generated/scanner.dart';
 import 'package:unittest/unittest.dart';
 
 import '../../reflective_tests.dart';
 import 'completion_test_util.dart';
 
 main() {
   groupSep = ' | ';
   runReflectiveTests(KeywordComputerTest);
 }
 
 @reflectiveTest
 class KeywordComputerTest extends AbstractCompletionTest {
 
-  void assertSuggestKeywords(Iterable<Keyword> expectedKeywords,
-      [int relevance = COMPLETION_RELEVANCE_DEFAULT]) {
+  void assertSuggestKeywords(Iterable<Keyword> expectedKeywords, [int relevance
+      = COMPLETION_RELEVANCE_DEFAULT]) {
     Set<Keyword> actualKeywords = new Set<Keyword>();
     request.suggestions.forEach((CompletionSuggestion s) {
       if (s.kind == CompletionSuggestionKind.KEYWORD) {
         Keyword k = Keyword.keywords[s.completion];
         if (k == null) {
           fail('Invalid keyword suggested: ${s.completion}');
         } else {
           if (!actualKeywords.add(k)) {
             fail('Duplicate keyword suggested: ${s.completion}');
           }
         }
-        expect(s.relevance, equals(relevance));
+        expect(s.relevance, equals(relevance), reason: k.toString());
         expect(s.selectionOffset, equals(s.completion.length));
         expect(s.selectionLength, equals(0));
         expect(s.isDeprecated, equals(false));
         expect(s.isPotential, equals(false));
       }
     });
     if (expectedKeywords.any((k) => k is String)) {
       StringBuffer msg = new StringBuffer();
       msg.writeln('Expected set should be:');
       expectedKeywords.forEach((n) {
@@ skipping 24 matching lines @@
         [
             Keyword.ABSTRACT,
             Keyword.CLASS,
             Keyword.CONST,
             Keyword.FINAL,
             Keyword.TYPEDEF,
             Keyword.VAR],
         COMPLETION_RELEVANCE_HIGH);
   }
 
+  test_after_class2() {
+    addTestSource('class A {} c^');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords(
+        [
+            Keyword.ABSTRACT,
+            Keyword.CLASS,
+            Keyword.CONST,
+            Keyword.FINAL,
+            Keyword.TYPEDEF,
+            Keyword.VAR],
+        COMPLETION_RELEVANCE_HIGH);
+  }
+
+  test_after_import() {
+    addTestSource('import foo; ^');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords(
+        [
+            Keyword.ABSTRACT,
+            Keyword.CLASS,
+            Keyword.CONST,
+            Keyword.EXPORT,
+            Keyword.FINAL,
+            Keyword.IMPORT,
+            Keyword.PART,
+            Keyword.TYPEDEF,
+            Keyword.VAR],
+        COMPLETION_RELEVANCE_HIGH);
+  }
+
+  test_after_import2() {
+    addTestSource('import foo; c^');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords(
+        [
+            Keyword.ABSTRACT,
+            Keyword.CLASS,
+            Keyword.CONST,
+            Keyword.EXPORT,
+            Keyword.FINAL,
+            Keyword.IMPORT,
+            Keyword.PART,
+            Keyword.TYPEDEF,
+            Keyword.VAR],
+        COMPLETION_RELEVANCE_HIGH);
+  }
+
   test_before_import() {
     addTestSource('^ import foo;');
     expect(computeFast(), isTrue);
     assertSuggestKeywords(
         [Keyword.EXPORT, Keyword.IMPORT, Keyword.LIBRARY, Keyword.PART],
         COMPLETION_RELEVANCE_HIGH);
   }
 
   test_class() {
     addTestSource('class A ^');
     expect(computeFast(), isTrue);
     assertSuggestKeywords(
         [Keyword.EXTENDS, Keyword.IMPLEMENTS],
         COMPLETION_RELEVANCE_HIGH);
   }
 
+  test_class2() {
+    addTestSource('class A e^');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords(
+        [Keyword.EXTENDS, Keyword.IMPLEMENTS],
+        COMPLETION_RELEVANCE_HIGH);
+  }
+
+  test_class3() {
+    addTestSource('class A e^ { }');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords(
+        [Keyword.EXTENDS, Keyword.IMPLEMENTS],
+        COMPLETION_RELEVANCE_HIGH);
+  }
+
   test_class_extends() {
     addTestSource('class A extends foo ^');
     expect(computeFast(), isTrue);
     assertSuggestKeywords(
         [Keyword.IMPLEMENTS, Keyword.WITH],
         COMPLETION_RELEVANCE_HIGH);
   }
 
+  test_class_extends2() {
+    addTestSource('class A extends foo i^');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords(
+        [Keyword.IMPLEMENTS, Keyword.WITH],
+        COMPLETION_RELEVANCE_HIGH);
+  }
+
+  test_class_extends3() {
+    addTestSource('class A extends foo i^ { }');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords(
+        [Keyword.IMPLEMENTS, Keyword.WITH],
+        COMPLETION_RELEVANCE_HIGH);
+  }
+
   test_class_extends_name() {
     addTestSource('class A extends ^');
     expect(computeFast(), isTrue);
     assertSuggestKeywords([]);
   }
 
   test_class_implements() {
     addTestSource('class A ^ implements foo');
     expect(computeFast(), isTrue);
     assertSuggestKeywords([Keyword.EXTENDS], COMPLETION_RELEVANCE_HIGH);
   }
 
+  test_class_implements2() {
+    addTestSource('class A e^ implements foo');
+    expect(computeFast(), isTrue);
+    // TODO (danrubel) refinement: don't suggest implements
+    assertSuggestKeywords(
+        [Keyword.EXTENDS, Keyword.IMPLEMENTS],
+        COMPLETION_RELEVANCE_HIGH);
+  }
+
+  test_class_implements3() {
+    addTestSource('class A e^ implements foo { }');
+    expect(computeFast(), isTrue);
+    // TODO (danrubel) refinement: don't suggest implements
+    assertSuggestKeywords(
+        [Keyword.EXTENDS, Keyword.IMPLEMENTS],
+        COMPLETION_RELEVANCE_HIGH);
+  }
+
   test_class_implements_name() {
     addTestSource('class A implements ^');
     expect(computeFast(), isTrue);
     assertSuggestKeywords([]);
   }
 
   test_class_name() {
     addTestSource('class ^');
     expect(computeFast(), isTrue);
     assertSuggestKeywords([]);
   }
 
+  test_class_with() {
+    addTestSource('class A extends foo with bar ^');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords([Keyword.IMPLEMENTS], COMPLETION_RELEVANCE_HIGH);
+  }
+
+  test_class_with2() {
+    addTestSource('class A extends foo with bar i^');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords([Keyword.IMPLEMENTS], COMPLETION_RELEVANCE_HIGH);
+  }
+
+  test_class_with3() {
+    addTestSource('class A extends foo with bar i^ { }');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords([Keyword.IMPLEMENTS], COMPLETION_RELEVANCE_HIGH);
+  }
+
   test_class_with_name() {
     addTestSource('class A extends foo with ^');
     expect(computeFast(), isTrue);
     assertSuggestKeywords([]);
   }
 
   test_empty() {
     addTestSource('^');
     expect(computeFast(), isTrue);
     assertSuggestKeywords(
@@ skipping 30 matching lines @@
             Keyword.SUPER,
             Keyword.SWITCH,
             Keyword.THIS,
             Keyword.THROW,
             Keyword.TRY,
             Keyword.VAR,
             Keyword.VOID,
             Keyword.WHILE]);
   }
 
+  test_function_body2() {
+    addTestSource('main() {{}^}');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords(
+        [
+            Keyword.ASSERT,
+            Keyword.CASE,
+            Keyword.CONTINUE,
+            Keyword.DO,
+            Keyword.FACTORY,
+            Keyword.FINAL,
+            Keyword.FOR,
+            Keyword.IF,
+            Keyword.NEW,
+            Keyword.RETHROW,
+            Keyword.RETURN,
+            Keyword.SUPER,
+            Keyword.SWITCH,
+            Keyword.THIS,
+            Keyword.THROW,
+            Keyword.TRY,
+            Keyword.VAR,
+            Keyword.VOID,
+            Keyword.WHILE]);
+  }
+
   test_in_class() {
     addTestSource('class A {^}');
     expect(computeFast(), isTrue);
     assertSuggestKeywords(
         [
             Keyword.CONST,
             Keyword.DYNAMIC,
             Keyword.FACTORY,
             Keyword.FINAL,
             Keyword.GET,
@@ skipping 117 matching lines @@
     sorted.forEach((k) => msg.writeln('  Keyword.${k.name},'));
   }
 
   bool _equalSets(Iterable<Keyword> iter1, Iterable<Keyword> iter2) {
     if (iter1.length != iter2.length) return false;
     if (iter1.any((k) => !iter2.contains(k))) return false;
     if (iter2.any((k) => !iter1.contains(k))) return false;
     return true;
   }
 }