Sharing metatest logic between unittest and scheduled_test

pkg/metatest/lib/metatest.dart

-// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
+// 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.
 
 /// A test library for testing test libraries? We must go deeper.
 ///
 /// Since unit testing code tends to use a lot of global state, it can be tough
 /// to test. This library manages it by running each test case in a child
 /// isolate, then reporting the results back to the parent isolate.
 library metatest;
 
 import 'dart:async';
-import 'dart:io';
 import 'dart:isolate';
 
-import 'package:path/path.dart' as path;
 import 'package:unittest/unittest.dart';
-import 'package:scheduled_test/scheduled_test.dart' as scheduled_test;
 
-import 'utils.dart';
+import 'src/utils.dart';
+
+/// Whether or not we're running in a child isolate that's supposed to run a
+/// test.
+bool _inChildIsolate;
+
+/// The port with which the child isolate should communicate with the parent
+/// isolate.
+///
+/// `null` in the parent isolate.
+SendPort _replyTo;
+
+/// The only value of the configuration used in metatest.
+final _metaConfiguration = new _MetaConfiguration();
+
+/// The function holding the tests to be run.
+Function _testBody;
+
+/// The description of the test to run in the child isolate.
+///
+/// `null` in the parent isolate.
+String _testToRun;
+
+/// Stores the optional timeout used to override the default unittest timeout.
+Duration _timeoutOverride;
+
+/// Runs [setUpFn] before every metatest.
+///
+/// Note that [setUpFn] will be overwritten if the test itself calls [setUp].
+void metaSetUp(void setUpFn()) {
+  if (_inChildIsolate) setUp(setUpFn);
+}
+
+/// Runs a set of tests defined in `body` and checks the result by comparing
+/// with values in `expectedResults`.
+///
+/// [expectedResults] is a list which should have a [Map] value for each test
+/// that is run. Each [Map] key corresponds to values from a completed test
+/// case: "description", "message", "result", and "stackTrace".
+///
+/// The value of "result" can be one of: 'pass', 'fail', or 'error'

[nweiz, 2014/09/18 22:16:03]

Add a period at the end of the sentence.

+///
+/// The value for "stackTrace" is the [String] 'null' if the property is `null`
+/// on the source test case. Otherwise, it is the output of `toString`.

[nweiz, 2014/09/18 22:16:03]

"the output of [toString]" is very unclear. What's [toString] being called on?

If this may be either a native StackTrace or a stack_trace trace, say so.
Alternately, just say that the format isn't guaranteed.

+///
+/// Here's an example of a `expectedResults` value for two tests, where the
+/// where the first fails and the second passes.
+///
+/// ```dart
+/// [{
+///   'description': 'test',
+///   'message': 'Caught error!',
+///   'result': 'fail',
+/// }, {
+///   'description': 'follow up',
+///   'result': 'pass',
+/// }]
+/// ```
+void expectTestResults(String description, void body(),
+    List<Map> expectedResults) {
+  _setUpTest(description, body, (resultsMap) {
+    var list = resultsMap['results'];
+    expect(list, hasLength(expectedResults.length),
+        reason: 'The number of tests run does not match the number of expected'
+          ' results.');
+
+    for (var i = 0; i < list.length; i++) {
+      var expectedMap = expectedResults[i];
+      var map = list[i];
+
+      expectedMap.forEach((key, value) {
+        expect(map, containsPair(key, value), reason: 'A test did not match the'
+          ' expected value for "$key" at index $i.');
+      });
+    }
+  });
+}
 
 /// Declares a test with the given [description] and [body]. [body] corresponds
 /// to the `main` method of a test file, and will be run in an isolate. By
 /// default, this expects that all tests defined in [body] pass, but if
 /// [passing] is passed, only tests listed there are expected to pass.
 void expectTestsPass(String description, void body(), {List<String> passing}) {
   _setUpTest(description, body, (results) {
     if (_hasError(results)) {
-      throw 'Expected all tests to pass, but got error(s):\n'
-          '${_summarizeTests(results)}';
+      fail('Expected all tests to pass, but got error(s):\n'
+          '${_summarizeTests(results)}');
     } else if (passing == null) {
       if (results['failed'] != 0) {
-        throw 'Expected all tests to pass, but some failed:\n'
-            '${_summarizeTests(results)}';
+        fail('Expected all tests to pass, but some failed:\n'
+            '${_summarizeTests(results)}');
       }
     } else {
       var shouldPass = new Set.from(passing);
       var didPass = new Set.from(results['results']
           .where((t) => t['result'] == 'pass')
           .map((t) => t['description']));
 
       if (!shouldPass.containsAll(didPass) ||
           !didPass.containsAll(shouldPass)) {
         String stringify(Set<String> tests) =>
-          '{${tests.map((t) => '"$t"').join(', ')}}';
+            '{${tests.map((t) => '"$t"').join(', ')}}';
 
         fail('Expected exactly ${stringify(shouldPass)} to pass, but '
             '${stringify(didPass)} passed.\n'
             '${_summarizeTests(results)}');
       }
     }
   });
 }
 
-/// Declares a test with the given [description] and [body].
-///
-/// [body] corresponds
-/// to the `main` method of a test file, and will be run in an isolate.
-///
-/// All tests must have an expected result in [expectedResults].
-void expectTests(String description, void body(),
-                 Map<String, String> expectedResults) {
-  _setUpTest(description, body, (results) {
-    expectedResults = new Map.from(expectedResults);
-
-    for (var testResult in results['results']) {
-      var description = testResult['description'];
-
-      expect(expectedResults, contains(description),
-          reason: '"$description" did not have an expected result set.\n'
-            '${_summarizeTests(results)}');
-
-      var result = testResult['result'];
-
-      expect(expectedResults, containsPair(description, result),
-          reason: 'The test "$description" not not have the expected result.\n'
-            '${_summarizeTests(results)}');
-
-      expectedResults.remove(description);
-    }
-    expect(expectedResults, isEmpty,
-        reason: 'Unexpected additional test results\n'
-            '${_summarizeTests(results)}');
-  });
-}
-
 /// Declares a test with the given [description] and [body]. [body] corresponds
 /// to the `main` method of a test file, and will be run in an isolate. Expects
 /// all tests defined by [body] to fail.
 void expectTestsFail(String description, void body()) {
   _setUpTest(description, body, (results) {
     if (_hasError(results)) {
       throw 'Expected all tests to fail, but got error(s):\n'
           '${_summarizeTests(results)}';
     } else if (results['passed'] != 0) {
       throw 'Expected all tests to fail, but some passed:\n'
           '${_summarizeTests(results)}';
     }
   });
 }
 
-/// Runs [setUpFn] before every metatest. Note that [setUpFn] will be
-/// overwritten if the test itself calls [setUp].
-void metaSetUp(void setUpFn()) {
-  if (_inChildIsolate) scheduled_test.setUp(setUpFn);
-}
-
 /// Sets up a test with the given [description] and [body]. After the test runs,
 /// calls [validate] with the result map.
-void _setUpTest(String description, void body(), void validate(Map)) {
+void _setUpTest(String description, void body(), void validate(Map map)) {
   if (_inChildIsolate) {
     _ensureInitialized();
     if (_testToRun == description) body();
   } else {
     test(description, () {
-      expect(_runInIsolate(description).then(validate), completes);
+      return _runInIsolate(description).then(validate);
     });
   }
 }
 
-/// The description of the test to run in the child isolate.
-///
-/// `null` in the parent isolate.
-String _testToRun;
-
-/// The port with which the child isolate should communicate with the parent
-/// isolate.
-///
-/// `null` in the parent isolate.
-SendPort _replyTo;
-
-/// Whether or not we're running in a child isolate that's supposed to run a
-/// test.
-bool _inChildIsolate;
-
 /// Initialize metatest.
 ///
 /// [message] should be the second argument to [main]. It's used to determine
 /// whether this test is in the parent isolate or a child isolate.
-void initMetatest(message) {
+///
+/// [timeout], when specified, overrides the default timeout for unittest.
+void initMetatest(message, {Duration timeout}) {
+  _timeoutOverride = timeout;
   if (message == null) {
     _inChildIsolate = false;
   } else {
     _testToRun = message['testToRun'];
     _replyTo = message['replyTo'];
     _inChildIsolate = true;
   }
 }
 
-/// Runs the test described by [description] in its own isolate. Returns a map
-/// describing the results of that test run.
+// TODO(kevmoo) We need to capture the main method to allow running in an
+// isolate. There is no mechanism to capture the current executing URI between
+// browser and vm. Issue 1145 and/or Issue 8440
+void initTests(void testBody(message)) {
+  _testBody = testBody;
+  _testBody(null);
+}
+
+/// Runs the test described by [description] in its own isolate.
+///
+/// Returns a map describing the results of that test run.
 Future<Map> _runInIsolate(String description) {
+  if (_testBody == null) {
+    throw new StateError('initTests was not called.');
+  }
+
   var replyPort = new ReceivePort();
-  // TODO(nweiz): Don't use path here once issue 8440 is fixed.
-  var uri = path.toUri(path.absolute(path.fromUri(Platform.script)));
-  return Isolate.spawnUri(uri, [], {
+  return Isolate.spawn(_testBody, {
     'testToRun': description,
     'replyTo': replyPort.sendPort
-  }).then((_) {
-    // TODO(nweiz): Remove this timeout once issue 8875 is fixed and we can
-    // capture top-level exceptions.
-    return timeout(replyPort.first, 30 * 1000, () {
-      throw 'Timed out waiting for test to complete.';
-    });
-  });
+  }).then((_) => replyPort.first);
 }
 
 /// Returns whether [results] (a test result map) describes a test run in which
 /// an error occurred.
 bool _hasError(Map results) {
   return results['errors'] > 0 || results['uncaughtError'] != null ||
       (results['passed'] == 0 && results['failed'] == 0);
 }
 
 /// Returns a string description of the test run descibed by [results].
@@ skipping 28 matching lines @@
   return prefixLines(buffer.toString());
 }
 
 /// Indents each line of [str] by two spaces.
 String _indent(String str) {
   return str.replaceAll(new RegExp("^", multiLine: true), "  ");
 }
 
 /// Ensure that the metatest configuration is loaded.
 void _ensureInitialized() {
-  unittestConfiguration = _singleton;
+  unittestConfiguration = _metaConfiguration;
+  if (_timeoutOverride != null) {
+    unittestConfiguration.timeout = _timeoutOverride;
+  }
 }
 
-final _singleton = new _MetaConfiguration();
-
 /// Special test configuration for use within the child isolates. This hides all
 /// output and reports data back to the parent isolate.
 class _MetaConfiguration extends Configuration {
 
   _MetaConfiguration() : super.blank();
 
   void onSummary(int passed, int failed, int errors, List<TestCase> results,
       String uncaughtError) {
     _replyTo.send({
       "passed": passed,
       "failed": failed,
       "errors": errors,
       "uncaughtError": uncaughtError,
       "results": results.map((testCase) => {
         "description": testCase.description,
         "message": testCase.message,
         "result": testCase.result,
         "stackTrace": testCase.stackTrace.toString()
       }).toList()
     });
   }
 }