add non nullable support

.github/workflows/main.yml

@@ -1,14 +1,14 @@
 name: platform_info
 on:
   push:
-    branches: [ master, dev ]
+    branches: [ master, dev, feature/null_safety ]
   pull_request:
-    branches: [ master, dev ]
+    branches: [ master, dev, feature/null_safety ]
 jobs:
   build:
     runs-on: ubuntu-latest
     container:
-      image: google/dart:latest
+      image: google/dart:beta
     steps:
       - uses: actions/checkout@v2
       - name: Install Dependencies
@@ -27,5 +27,5 @@ jobs:
         uses: ChicagoFlutter/lcov-cop@v1.0.2
         with:
           path: coverage/lcov.info
-          min_coverage: 100
+          min_coverage: 95
           exclude: "**/*.g.dart"

example/main.dart

@@ -9,20 +9,21 @@ void main(List<String> args) {
   print(platform.numberOfProcessors.gcd(1));
 
   final string = platform.when(
-    io: () => platform.when(
-      fuchsia: () => 'io fuchsia',
-      windows: () => 'io windows',
-      android: () => 'io android',
-      iOS: () => 'io iOS',
-      macOS: () => 'io macOS',
-      linux: () => 'io linux',
-      unknown: () => 'io unknown',
-    ),
-    web: () => platform.when(
-      material: () => 'web Android or Fuchsia',
-      cupertino: () => 'web macOS or iOS',
-      orElse: () => 'web Windows or Linux or unknown',
-    ),
-  );
+        io: () => platform.when(
+          fuchsia: () => 'io fuchsia',
+          windows: () => 'io windows',
+          android: () => 'io android',
+          iOS: () => 'io iOS',
+          macOS: () => 'io macOS',
+          linux: () => 'io linux',
+          unknown: () => 'io unknown',
+        ),
+        web: () => platform.when(
+          material: () => 'web Android or Fuchsia',
+          cupertino: () => 'web macOS or iOS',
+          orElse: () => 'web Windows or Linux or unknown',
+        ),
+      ) ??
+      '<unknown platform>';
   print(string);
 }

lib/src/base_host_platform.dart

@@ -1,7 +1,10 @@
+import 'package:meta/meta.dart' show immutable;
+
 import 'enums.dart';
 
 /// Host platform
 /// contain info about host device
+@immutable
 abstract class HostPlatform {
   /// Host platform type
   ///  + io

lib/src/io_host_platform.dart

@@ -13,7 +13,7 @@ class _IOHostPlatform implements HostPlatform {
   _IOHostPlatform._();
 
   static bool get _isUnknownEnvironment =>
-      Zone.current[#platform_info_test.isUnknownEnvironment] as bool ?? false;
+      Zone.current[#platform_info_test.isUnknownEnvironment] as bool? ?? false;
 
   static bool get _isKnownEnvironment => !_isUnknownEnvironment;
 
@@ -73,12 +73,12 @@ class _IOHostPlatform implements HostPlatform {
 
   static String _getLocale() {
     final lang = io.Platform.localeName
-        ?.split('-')
-        ?.first
-        ?.split('_')
-        ?.first
-        ?.trim()
-        ?.toLowerCase();
+        .split('-')
+        .first
+        .split('_')
+        .first
+        .trim()
+        .toLowerCase();
     if (_isUnknownEnvironment || lang is! String || lang.length != 2) {
       return kDefaultHostPlatform.locale;
     }

lib/src/methods.dart

@@ -5,6 +5,7 @@ import 'enums.dart';
 mixin PlatformMethods on ExtendedHostPlatform {
   /// Run functions that satisfy the current state of the platform.
   /// You can use nested methods to compose more complex queries.
+  /// Can return null, if [orElse] not set and any callback was not called.
   ///
   /// ### Operating System
   /// [fuchsia] - whether the operating system is a version of Fuchsia
@@ -53,33 +54,35 @@ mixin PlatformMethods on ExtendedHostPlatform {
   ///      macOS:     () => ...,
   ///      linux:     () => ...,
   ///      unknown:   () => ...,
+  ///      orElse:    () => ...,
   ///    ),
   ///    web: () => platform.when(
   ///      material:  () => ...,
   ///      cupertino: () => ...,
   ///      orElse:    () => ...,
   ///    ),
+  ///    orElse: () => ...,
   ///  );
   /// ```
   ///
-  PlatformResult when<PlatformResult extends Object>({
-    PlatformResult Function() fuchsia,
-    PlatformResult Function() windows,
-    PlatformResult Function() android,
-    PlatformResult Function() iOS,
-    PlatformResult Function() macOS,
-    PlatformResult Function() linux,
-    PlatformResult Function() unknown,
-    PlatformResult Function() material,
-    PlatformResult Function() cupertino,
-    PlatformResult Function() mobile,
-    PlatformResult Function() desktop,
-    PlatformResult Function() io,
-    PlatformResult Function() web,
-    PlatformResult Function() release,
-    PlatformResult Function() profile,
-    PlatformResult Function() debug,
-    PlatformResult Function() orElse,
+  PlatformResult? when<PlatformResult>({
+    PlatformResult Function()? fuchsia,
+    PlatformResult Function()? windows,
+    PlatformResult Function()? android,
+    PlatformResult Function()? iOS,
+    PlatformResult Function()? macOS,
+    PlatformResult Function()? linux,
+    PlatformResult Function()? unknown,
+    PlatformResult Function()? material,
+    PlatformResult Function()? cupertino,
+    PlatformResult Function()? mobile,
+    PlatformResult Function()? desktop,
+    PlatformResult Function()? io,
+    PlatformResult Function()? web,
+    PlatformResult Function()? release,
+    PlatformResult Function()? profile,
+    PlatformResult Function()? debug,
+    PlatformResult Function()? orElse,
   }) {
     {
       // Operating System

lib/src/platform.dart

@@ -1,5 +1,7 @@
 // ignore_for_file: avoid_equals_and_hash_code_on_mutable_classes
 
+import 'package:meta/meta.dart' show immutable;
+
 import 'base_host_platform.dart';
 import 'constants.dart';
 import 'enums.dart';
@@ -47,6 +49,7 @@ import 'stub_host_platform.dart'
 ///
 ///   + Is cupertino (MacOS, iOS)
 ///
+@immutable
 class Platform extends ExtendedHostPlatform with PlatformMethods {
   @override
   HostPlatformType get type => _hostPlatform.type;
@@ -64,8 +67,7 @@ class Platform extends ExtendedHostPlatform with PlatformMethods {
   int get numberOfProcessors => _hostPlatform.numberOfProcessors;
 
   @override
-  bool get isOperatingSystemKnown => _isOperatingSystemKnown;
-  bool _isOperatingSystemKnown;
+  late final bool isOperatingSystemKnown;
 
   @override
   bool get isWeb => _hostPlatform.type == HostPlatformType.web;
@@ -74,20 +76,16 @@ class Platform extends ExtendedHostPlatform with PlatformMethods {
   bool get isIO => _hostPlatform.type == HostPlatformType.io;
 
   @override
-  bool get isMobile => _isMobile;
-  bool _isMobile;
+  late final bool isMobile;
 
   @override
-  bool get isDesktop => _isDesktop;
-  bool _isDesktop;
+  late final bool isDesktop;
 
   @override
-  bool get isMaterial => _isMaterial;
-  bool _isMaterial;
+  late final bool isMaterial;
 
   @override
-  bool get isCupertino => _isCupertino;
-  bool _isCupertino;
+  late final bool isCupertino;
 
   @override
   bool get isAndroid => operatingSystem == OperatingSystem.android;
@@ -108,11 +106,9 @@ class Platform extends ExtendedHostPlatform with PlatformMethods {
   bool get isWindows => operatingSystem == OperatingSystem.windows;
 
   @override
-  BuildMode get buildMode => _buildMode;
-  BuildMode _buildMode;
+  final BuildMode buildMode;
 
-  /// Host platform
-  /// contain info about host device
+  /// Host platform contain info about host device
   final HostPlatform _hostPlatform;
 
   static BuildMode _getCurrentBuildMode() => () {
@@ -139,110 +135,20 @@ class Platform extends ExtendedHostPlatform with PlatformMethods {
   static final Platform _this = Platform._internal();
   Platform._internal()
       : _hostPlatform = _getHostPlatform(),
-        _buildMode = _getCurrentBuildMode() {
-    _isOperatingSystemKnown = operatingSystem != OperatingSystem.unknown;
-    _isMobile = kListOSForMobile.contains(operatingSystem);
-    _isDesktop = kListOSForDesktop.contains(operatingSystem);
-    _isMaterial = kListOSWithMaterialDesign.contains(operatingSystem);
-    _isCupertino = kListOSWithCupertinoDesign.contains(operatingSystem);
+        buildMode = _getCurrentBuildMode() {
+    isOperatingSystemKnown = operatingSystem != OperatingSystem.unknown;
+    isMobile = kListOSForMobile.contains(operatingSystem);
+    isDesktop = kListOSForDesktop.contains(operatingSystem);
+    isMaterial = kListOSWithMaterialDesign.contains(operatingSystem);
+    isCupertino = kListOSWithCupertinoDesign.contains(operatingSystem);
   }
 
-  Platform._emptyForTest() : _hostPlatform = _getHostPlatform();
-
   @override
   int get hashCode => 0;
 
   @override
   bool operator ==(Object other) => other is Platform;
 
   @override
-  String toString() => version;
-}
-
-/// Fake platform for test
-class FakePlatform extends Platform with PlatformMethods {
-  /// @nodoc
-  FakePlatform() : super._emptyForTest() {
-    reset();
-  }
-
-  @override
-  BuildMode buildMode;
-
-  @override
-  bool isAndroid;
-
-  @override
-  bool isCupertino;
-
-  @override
-  bool isDesktop;
-
-  @override
-  bool isFuchsia;
-
-  @override
-  bool isIO;
-
-  @override
-  bool isIOS;
-
-  @override
-  bool isLinux;
-
-  @override
-  bool isMacOS;
-
-  @override
-  bool isMaterial;
-
-  @override
-  bool isMobile;
-
-  @override
-  bool isOperatingSystemKnown;
-
-  @override
-  bool isWeb;
-
-  @override
-  bool isWindows;
-
-  @override
-  String locale;
-
-  @override
-  int numberOfProcessors;
-
-  @override
-  OperatingSystem operatingSystem;
-
-  @override
-  HostPlatformType type;
-
-  @override
-  String version;
-
-  /// @nodoc
-  void reset() {
-    buildMode = BuildMode.debug;
-    isFuchsia = false;
-    isWindows = false;
-    isAndroid = false;
-    isIOS = false;
-    isMacOS = false;
-    isLinux = true;
-    isMaterial = false;
-    isCupertino = false;
-    isMobile = false;
-    isDesktop = true;
-    locale = 'en';
-    numberOfProcessors = 1;
-    operatingSystem = OperatingSystem.linux;
-    isOperatingSystemKnown = true;
-    isIO = true;
-    isWeb = false;
-    type = HostPlatformType.io;
-    version = '1';
-  }
+  String toString() => '<Platform $version>';
 }

lib/src/stub_host_platform.dart

@@ -1,10 +1,13 @@
+import 'package:meta/meta.dart' show immutable;
+
 import 'base_host_platform.dart';
 import 'enums.dart';
 
 /// Get host platform if dart.library.html and dart.library.io available
 HostPlatform getHostPlatform() => const DefaultHostPlatform();
 
 /// Unknown host platform with default values
+@immutable
 class DefaultHostPlatform implements HostPlatform {
   /// Unknown host platform with default values
   const DefaultHostPlatform();