Enable and fix package:pedantic lints (flutter#135)

- always_declare_return_types
- omit_local_variable_types
- prefer_collection_literals
- prefer_if_null_operators
- unawaited_futures

Bump min SDK to 2.2.0 to support Set literals.

Author: natebosch

analysis_options.yaml

@@ -1,3 +1,4 @@
+include: package:pedantic/analysis_options.1.9.0.yaml
 linter:
   rules:
     - annotate_overrides

example/example.dart

@@ -32,17 +32,17 @@ Analytics getAnalytics() {
 }
 
 void _handleFoo() {
-  Analytics analytics = getAnalytics();
+  var analytics = getAnalytics();
   analytics.sendEvent('main', 'foo');
 }
 
 void _handleBar() {
-  Analytics analytics = getAnalytics();
+  var analytics = getAnalytics();
   analytics.sendEvent('main', 'bar');
 }
 
 void _changePage() {
-  Analytics analytics = getAnalytics();
+  var analytics = getAnalytics();
   window.history.pushState(null, 'new page', '${++_count}.html');
   analytics.sendScreenView(window.location.pathname);
 }

example/ga.dart

@@ -7,8 +7,8 @@ library usage_ga;
 
 import 'package:usage/usage_io.dart';
 
-main(List args) async {
-  final String defaultUA = 'UA-55029513-1';
+void main(List args) async {
+  final defaultUA = 'UA-55029513-1';
 
   if (args.isEmpty) {
     print('usage: dart ga <GA tracking ID>');

lib/src/usage_impl.dart

@@ -11,7 +11,7 @@ import '../uuid/uuid.dart';
 String postEncode(Map<String, dynamic> map) {
   // &foo=bar
   return map.keys.map((key) {
-    String value = '${map[key]}';
+    var value = '${map[key]}';
     return '${key}=${Uri.encodeComponent(value)}';
   }).join('&');
 }
@@ -44,10 +44,10 @@ class ThrottlingBucket {
   }
 
   void _checkReplenish() {
-    int now = DateTime.now().millisecondsSinceEpoch;
+    var now = DateTime.now().millisecondsSinceEpoch;
 
     if (_lastReplenish + 1000 >= now) {
-      int inc = (now - _lastReplenish) ~/ 1000;
+      var inc = (now - _lastReplenish) ~/ 1000;
       drops = math.min(drops + inc, startingCount);
       _lastReplenish += (1000 * inc);
     }
@@ -108,7 +108,7 @@ class AnalyticsImpl implements Analytics {
 
   @override
   bool get enabled {
-    bool optIn = analyticsOpt == AnalyticsOpt.optIn;
+    var optIn = analyticsOpt == AnalyticsOpt.optIn;
     return optIn
         ? properties['enabled'] == true
         : properties['enabled'] != false;
@@ -121,7 +121,7 @@ class AnalyticsImpl implements Analytics {
 
   @override
   Future sendScreenView(String viewName, {Map<String, String> parameters}) {
-    Map<String, dynamic> args = {'cd': viewName};
+    var args = <String, dynamic>{'cd': viewName};
     if (parameters != null) {
       args.addAll(parameters);
     }
@@ -131,7 +131,7 @@ class AnalyticsImpl implements Analytics {
   @override
   Future sendEvent(String category, String action,
       {String label, int value, Map<String, String> parameters}) {
-    Map<String, dynamic> args = {'ec': category, 'ea': action};
+    var args = <String, dynamic>{'ec': category, 'ea': action};
     if (label != null) args['el'] = label;
     if (value != null) args['ev'] = value;
     if (parameters != null) {
@@ -142,14 +142,14 @@ class AnalyticsImpl implements Analytics {
 
   @override
   Future sendSocial(String network, String action, String target) {
-    Map<String, dynamic> args = {'sn': network, 'sa': action, 'st': target};
+    var args = <String, dynamic>{'sn': network, 'sa': action, 'st': target};
     return _sendPayload('social', args);
   }
 
   @override
   Future sendTiming(String variableName, int time,
       {String category, String label}) {
-    Map<String, dynamic> args = {'utv': variableName, 'utt': time};
+    var args = <String, dynamic>{'utv': variableName, 'utt': time};
     if (label != null) args['utl'] = label;
     if (category != null) args['utc'] = category;
     return _sendPayload('timing', args);
@@ -165,7 +165,7 @@ class AnalyticsImpl implements Analytics {
   Future sendException(String description, {bool fatal}) {
     // We trim exceptions to a max length; google analytics will apply it's own
     // truncation, likely around 150 chars or so.
-    const int maxExceptionLength = 1000;
+    const maxExceptionLength = 1000;
 
     // In order to ensure that the client of this API is not sending any PII
     // data, we strip out any stack trace that may reference a path on the
@@ -180,7 +180,7 @@ class AnalyticsImpl implements Analytics {
       description = description.substring(0, maxExceptionLength);
     }
 
-    Map<String, dynamic> args = {'exd': description};
+    var args = <String, dynamic>{'exd': description};
     if (fatal != null && fatal) args['exf'] = '1';
     return _sendPayload('exception', args);
   }

lib/src/usage_impl_html.dart

@@ -21,8 +21,8 @@ class AnalyticsHtml extends AnalyticsImpl {
             applicationName: applicationName,
             applicationVersion: applicationVersion,
             analyticsUrl: analyticsUrl) {
-    int screenWidth = window.screen.width;
-    int screenHeight = window.screen.height;
+    var screenWidth = window.screen.width;
+    var screenHeight = window.screen.height;
 
     setSessionValue('sr', '${screenWidth}x$screenHeight');
     setSessionValue('sd', '${window.screen.pixelDepth}-bits');
@@ -40,14 +40,13 @@ class HtmlPostHandler extends PostHandler {
 
   @override
   Future sendPost(String url, Map<String, dynamic> parameters) {
-    int viewportWidth = document.documentElement.clientWidth;
-    int viewportHeight = document.documentElement.clientHeight;
+    var viewportWidth = document.documentElement.clientWidth;
+    var viewportHeight = document.documentElement.clientHeight;
 
     parameters['vp'] = '${viewportWidth}x$viewportHeight';
 
-    String data = postEncode(parameters);
-    HttpRequestor requestor =
-        mockRequestor == null ? HttpRequest.request : mockRequestor;
+    var data = postEncode(parameters);
+    var requestor = mockRequestor ?? HttpRequest.request;
     return requestor(url, method: 'POST', sendData: data).catchError((e) {
       // Catch errors that can happen during a request, but that we can't do
       // anything about, e.g. a missing internet connection.
@@ -62,7 +61,7 @@ class HtmlPersistentProperties extends PersistentProperties {
   Map _map;
 
   HtmlPersistentProperties(String name) : super(name) {
-    String str = window.localStorage[name];
+    var str = window.localStorage[name];
     if (str == null || str.isEmpty) str = '{}';
     _map = jsonDecode(str);
   }

lib/src/usage_impl_io.dart

@@ -33,15 +33,15 @@ class AnalyticsIO extends AnalyticsImpl {
             applicationName: applicationName,
             applicationVersion: applicationVersion,
             analyticsUrl: analyticsUrl) {
-    final String locale = getPlatformLocale();
+    final locale = getPlatformLocale();
     if (locale != null) {
       setSessionValue('ul', locale);
     }
   }
 }
 
 String _createUserAgent() {
-  final String locale = getPlatformLocale() ?? '';
+  final locale = getPlatformLocale() ?? '';
 
   if (Platform.isAndroid) {
     return 'Mozilla/5.0 (Android; Mobile; ${locale})';
@@ -55,20 +55,20 @@ String _createUserAgent() {
     return 'Mozilla/5.0 (Linux; Linux; Linux; ${locale})';
   } else {
     // Dart/1.8.0 (macos; macos; macos; en_US)
-    String os = Platform.operatingSystem;
+    var os = Platform.operatingSystem;
     return 'Dart/${getDartVersion()} (${os}; ${os}; ${os}; ${locale})';
   }
 }
 
 String userHomeDir() {
-  String envKey = Platform.operatingSystem == 'windows' ? 'APPDATA' : 'HOME';
-  String value = Platform.environment[envKey];
-  return value == null ? '.' : value;
+  var envKey = Platform.operatingSystem == 'windows' ? 'APPDATA' : 'HOME';
+  var value = Platform.environment[envKey];
+  return value ?? '.';
 }
 
 String getDartVersion() {
-  String ver = Platform.version;
-  int index = ver.indexOf(' ');
+  var ver = Platform.version;
+  var index = ver.indexOf(' ');
   if (index != -1) ver = ver.substring(0, index);
   return ver;
 }
@@ -83,18 +83,18 @@ class IOPostHandler extends PostHandler {
 
   @override
   Future sendPost(String url, Map<String, dynamic> parameters) async {
-    String data = postEncode(parameters);
+    var data = postEncode(parameters);
 
     if (_client == null) {
-      _client = mockClient != null ? mockClient : HttpClient();
+      _client = mockClient ?? HttpClient();
       _client.userAgent = _userAgent;
     }
 
     try {
-      HttpClientRequest req = await _client.postUrl(Uri.parse(url));
+      var req = await _client.postUrl(Uri.parse(url));
       req.write(data);
-      HttpClientResponse response = await req.close();
-      response.drain();
+      var response = await req.close();
+      await response.drain();
     } catch (exception) {
       // Catch errors that can happen during a request, but that we can't do
       // anything about, e.g. a missing internet connection.
@@ -112,7 +112,7 @@ class IOPersistentProperties extends PersistentProperties {
   Map _map;
 
   IOPersistentProperties(String name, {String documentDirPath}) : super(name) {
-    String fileName = '.${name.replaceAll(' ', '_')}';
+    var fileName = '.${name.replaceAll(' ', '_')}';
     documentDirPath ??= userHomeDir();
     _file = File(path.join(documentDirPath, fileName));
     if (!_file.existsSync()) {
@@ -151,7 +151,7 @@ class IOPersistentProperties extends PersistentProperties {
   @override
   void syncSettings() {
     try {
-      String contents = _file.readAsStringSync();
+      var contents = _file.readAsStringSync();
       if (contents.isEmpty) contents = '{}';
       _map = jsonDecode(contents);
     } catch (_) {
@@ -163,12 +163,12 @@ class IOPersistentProperties extends PersistentProperties {
 /// Return the string for the platform's locale; return's `null` if the locale
 /// can't be determined.
 String getPlatformLocale() {
-  String locale = Platform.localeName;
+  var locale = Platform.localeName;
   if (locale == null) return null;
 
   if (locale != null) {
     // Convert `en_US.UTF-8` to `en_US`.
-    int index = locale.indexOf('.');
+    var index = locale.indexOf('.');
     if (index != -1) locale = locale.substring(0, index);
 
     // Convert `en_US` to `en-us`.

lib/usage.dart

@@ -294,13 +294,13 @@ class AnalyticsMock implements Analytics {
 /// an exception. This will try and make those first 100 chars contain
 /// information useful to debugging the issue.
 String sanitizeStacktrace(dynamic st, {bool shorten = true}) {
-  String str = '${st}';
+  var str = '${st}';
 
   Iterable<Match> iter = _pathRegex.allMatches(str);
   iter = iter.toList().reversed;
 
-  for (Match match in iter) {
-    String replacement = match.group(1);
+  for (var match in iter) {
+    var replacement = match.group(1);
     str =
         str.substring(0, match.start) + replacement + str.substring(match.end);
   }

lib/uuid/uuid.dart

@@ -23,7 +23,7 @@ class Uuid {
   /// random numbers as the source of the generated uuid.
   String generateV4() {
     // Generate xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx / 8-4-4-4-12.
-    int special = 8 + _random.nextInt(4);
+    var special = 8 + _random.nextInt(4);
 
     return '${_bitsDigits(16, 4)}${_bitsDigits(16, 4)}-'
         '${_bitsDigits(16, 4)}-'

pubspec.yaml

@@ -9,11 +9,12 @@ homepage: https://github.com/dart-lang/usage
 author: Dart Team <misc@dartlang.org>
 
 environment:
-  sdk: '>=2.0.0-dev.30 <3.0.0'
+  sdk: '>=2.2.0 <3.0.0'
 
 dependencies:
   path: ^1.4.0
 
 dev_dependencies:
   grinder: ^0.8.0
+  pedantic: ^1.9.0
   test: ^1.0.0