all: feat async and memory safe high level API

Async Communication

- posting messages to dart via isolate via response channel on dart side
- response channel provides useful error for dangling replies
- rwlock to protect Store access
- including store.runLocked convenience Dart function
- timeout warn logs for msg calls

Memory Safe API

- pointers wrap `RawStruct` Dart classes which have a safer `Struct`
  version returned via safer API
- including rid widget helpers in generated code
- derive DartObject implementation for all `rid::model`s and `rid::store`s
- dart class includes equality operators and `toString`
- rendering `toDart` method for disposable vec
- store lock/unlock is logged on Dart end

Macros

- added store, related trait and message reply
- requiring that #[rid::store] struct be named 'Store'
- adding RidStore trait making it easier to implement needed Store
  methods
- `rid::model` detects `Debug` and `Clone`, debug is exposed to Dart for
  structs and enums

Added Type Support

- `Option<T>` return type represented as `T?` on Dart end
- bool args handled correctly
- rewriting binding.h to work around ffigen issues with type aliases
- Enums are converted to Dart with same name as they had in Rust, args
  and returned enums now have same type

Fixes

- fix hot restart

Examples

- clock example to demonstrate threading
- todo example adapted to latest API

Closes: #3
Closes: #2

Cargo.toml

@@ -11,7 +11,11 @@ members=[
   "rid-ffi",
   "rid-macro",
   "rid-macro-impl",
-  "examples/dart/todo"
+]
+exclude = [ 
+  "examples/dart/clock",
+  "examples/dart/todo",
+  "examples/dart/wip",
 ]
 
 [dependencies]

examples/dart/clock/.gitignore

@@ -0,0 +1,18 @@
+lib/generated/*
+
+**/doc/api/
+.dart_tool/
+.flutter-plugins
+.flutter-plugins-dependencies
+**/generated_plugin_registrant.dart
+.packages
+.pub-cache/
+.pub/
+build/
+flutter_*.png
+linked_*.ds
+unlinked.ds
+unlinked_spec.ds
+
+target/
+Cargo.lock

examples/dart/clock/Cargo.toml

@@ -0,0 +1,23 @@
+[package]
+name = "clock"
+version = "0.1.0"
+authors = ["Thorsten Lorenz <[email protected]>"]
+edition = "2018"
+
+[lib]
+name = "clock"
+crate-type = ["cdylib"]
+path = "src/lib.rs"
+doctest = false
+test = false
+
+[[bin]]
+name = "rid_build"
+path = "rid_build.rs"
+
+[dependencies]
+rid = { path = "../../../" }
+rid_build = { path = "../../../rid-build" }
+
+[build-dependencies]
+rid_build = { path = "../../../rid-build" }

examples/dart/clock/lib/keyboard_handler.dart

@@ -0,0 +1,67 @@
+import 'dart:io';
+
+import 'package:clock/generated/rid_generated.dart';
+import 'package:clock/stop_watch.dart';
+
+class KeyboardHandler {
+  final StopWatch stopWatch;
+  final Store store;
+
+  KeyboardHandler(this.store, this.stopWatch);
+
+  printStatus() {
+    print('${store.raw.debug(true)}');
+  }
+
+  void printCommands() {
+    print("\nPlease select one of the below:\n");
+    print("  a       -- to start clock");
+    print("  o       -- to stop clock");
+    print("  r       -- to reset clock");
+    print("  q       -- to quit");
+  }
+
+  Future<bool> handleCommand(String cmd) async {
+    switch (cmd) {
+      case "a":
+        await stopWatch.startTimer();
+        break;
+      case "o":
+        await stopWatch.stopTimer();
+        break;
+      case "r":
+        await stopWatch.resetTimer();
+        break;
+      case "q":
+        return false;
+      default:
+        print("\nUnknown command '$cmd'\n");
+        return false;
+    }
+    return true;
+  }
+
+  void resetScreen() {
+    print("\x1B[2J\x1B[0;0H");
+    printStatus();
+    printCommands();
+    stdout.write("\n> ");
+  }
+
+  void start() async {
+    resetScreen();
+    replyChannel.stream.where((res) => res.type == Reply.Tick).listen((_) {
+      ridStoreLock();
+      resetScreen();
+      ridStoreUnlock();
+    });
+    stdin.listen((bytes) async {
+      final cmd = String.fromCharCode(bytes.first);
+      final ok = await handleCommand(cmd);
+      if (!ok || cmd == "q") {
+        exit(0);
+      }
+      resetScreen();
+    });
+  }
+}

examples/dart/clock/lib/main.dart

@@ -0,0 +1,13 @@
+import 'dart:async';
+
+import 'package:clock/generated/rid_generated.dart';
+import 'package:clock/keyboard_handler.dart';
+import 'package:clock/stop_watch.dart';
+
+Future<void> main() async {
+  final store = Store.instance;
+  final stopWatch = StopWatch(store);
+  final handler = new KeyboardHandler(store, stopWatch);
+  handler.start();
+  print("Waiting for the response, but life goes on\n");
+}

examples/dart/clock/lib/stop_watch.dart

@@ -0,0 +1,22 @@
+import 'package:clock/generated/rid_generated.dart';
+
+class StopWatch {
+  final Store store;
+
+  StopWatch(this.store);
+
+  Future<void> startTimer() async {
+    final res = await store.msgStart();
+    print('$res');
+  }
+
+  Future<void> stopTimer() async {
+    final res = await store.msgStop();
+    print('$res');
+  }
+
+  Future<void> resetTimer() async {
+    final res = await store.msgReset();
+    print('$res');
+  }
+}