Map literal incorrectly casted to abstract on IMap on CS target

[romanmikhailov]

I have an abstract on IMap (AbstractMap in example below), Implementation of IMap interface with custom key constraint from abstract class (FooMap in example below).

In my AbstractMap I have @:from and @:to methods to allow constructing of my map.

And for dynamic targets example below works correctly but I receives runtime exception (running on js and C# targets listings in the end of message) in C#:

Main.hx:

package;

import haxe.ds.IntMap;
import haxe.ds.ObjectMap;
import haxe.Constraints.IMap;

typedef GlobalIdPair = {
	id: Int,
	value: Dynamic
}

class GlobalIdStorage {
	private static var idMap:IntMap<GlobalIdPair> = new IntMap<GlobalIdPair>();
	private static var lastId:Int = 0;

	public static function createId(object:Dynamic):Int {
		lastId++;
		idMap.set(lastId, {
			id: lastId,
			value: object
		});
		return lastId;
	}

	public static function getIdForObject(object:Dynamic):Int {
		for (it in idMap) {
			if (it.value == object) {
				return it.id;
			}
		}
		return -1;
	}

	public static function getObjectForId(id:Int):Null<Dynamic> {
		return idMap.exists(id) ? idMap.get(id).value : null;
	}
}

abstract Foo<T>(T) {
	public function new(t:T) {
		this = t;
		GlobalIdStorage.createId(t);
	}

	public function getId():Int {
		return GlobalIdStorage.getIdForObject(this);
	}
}

class FooMap<K:Foo<Dynamic>, V> implements Map.IMap<K, V> {
	var h:IntMap<V>;

	public inline function new() {
	    h = new IntMap<V>();
	}

	public function get(k:K):Null<V> {
	    return h.get(k.getId());
	}

	public function set(k:K, v:V) {
		h.set(k.getId(), v);
	}

	public function exists(k:K):Bool {
		return h.exists(k.getId());
	}

	public function remove(k:K):Bool {
		return h.remove(k.getId());
	}

	public function keys():Iterator<K> {
		var i = h.keys();
		return {
			hasNext: i.hasNext,
			next: function():K {
				return GlobalIdStorage.getObjectForId(i.next());
			}
		}
	}

	public inline function iterator():Iterator<V> {
		return h.iterator();
	}

	public inline function toString():String {
		return h.toString();
	}
}

@:multiType
@:forward(exists, get, set)
abstract AbstractMap<K, V>(IMap<K, V>) {
	public function new();

	@:to 
	public static inline function toFooMap<K:Foo<Dynamic>, V>(map:IMap<K, V>):FooMap<K, V> {
		return new FooMap<K, V>();
	}

	@:from static inline function fromHaxeMap<K, V>(map:Map<K, V>):AbstractMap<K, V> {
		return cast map;
	}
}

class Main {
	public static function main():Void {
		var abstractMap:AbstractMap<Foo<String>, String> = [new Foo<String>("Foo<String>0") => "String0", new Foo<String>("Foo<String>1") => "String1"];

		trace(abstractMap.exists(new Foo<String>("Foo<String>0")));
		trace(abstractMap.get(new Foo<String>("Foo<String>0")));

		trace(abstractMap.exists(new Foo<String>("Foo<String>1")));
		trace(abstractMap.get(new Foo<String>("Foo<String>1")));

		trace(abstractMap.exists(new Foo<String>("Foo<String>2")));
		trace(abstractMap.get(new Foo<String>("Foo<String>2")));
	}
}

build.hxml:

-cs bin/cs

-cp .
-main Main
-dce full
-debug
-D real-position

-cmd mono bin/cs/bin/Main-Debug.exe

build_js.hxml:

-js bin/js/main.js

-cp .
-main Main
-dce full
-debug

-cmd node bin/js/main.js

JS output:

$ haxe build_js.hxml 
true
String0
true
String1
false
undefined

CS output:

$ haxe build.hxml 
haxelib run hxcs hxcs_build.txt --haxe-version 3402 --feature-level 1
Note: dmcs is deprecated, please use mcs instead!

Unhandled Exception:
System.InvalidCastException: Specified cast is not valid.
  at Main.main () [0x0005a] in <b6f74a2b4df84d9e9f088683dc02b1a3>:0 
  at EntryPoint__Main.Main () [0x00007] in <b6f74a2b4df84d9e9f088683dc02b1a3>:0 
[ERROR] FATAL UNHANDLED EXCEPTION: System.InvalidCastException: Specified cast is not valid.
  at Main.main () [0x0005a] in <b6f74a2b4df84d9e9f088683dc02b1a3>:0 
  at EntryPoint__Main.Main () [0x00007] in <b6f74a2b4df84d9e9f088683dc02b1a3>:0 
Error: Command failed with error 1

Generated C# main method:

public static void main() {
		unchecked {
			global::haxe.IMap<object, object> _g = ((global::haxe.IMap<object, object>) (global::haxe.IMap__Statics_.__hx_cast<object, object>(((global::haxe.IMap) (new global::haxe.ds.StringMap<object>()) ))) );
			_g.@set(global::haxe.lang.Runtime.toString(global::_Main.Foo_Impl_._new<object>(((object) ("Foo<String>0") ))), "String0");
			_g.@set(global::haxe.lang.Runtime.toString(global::_Main.Foo_Impl_._new<object>(((object) ("Foo<String>1") ))), "String1");
			global::FooMap<object, object> abstractMap = ((global::FooMap<object, object>) (global::FooMap<object, object>.__hx_cast<object, object>(((global::FooMap) (_g) ))) );
			global::haxe.Log.trace.__hx_invoke2_o(default(double), abstractMap.exists(global::haxe.lang.Runtime.toString(global::_Main.Foo_Impl_._new<object>(((object) ("Foo<String>0") )))), default(double), new global::haxe.lang.DynamicObject(new int[]{302979532, 1547539107, 1648581351}, new object[]{"main", "Main", "Main.hx"}, new int[]{1981972957}, new double[]{((double) (111) )}));
			global::haxe.Log.trace.__hx_invoke2_o(default(double), global::haxe.lang.Runtime.toString((abstractMap.@get(global::haxe.lang.Runtime.toString(global::_Main.Foo_Impl_._new<object>(((object) ("Foo<String>0") ))))).toDynamic()), default(double), new global::haxe.lang.DynamicObject(new int[]{302979532, 1547539107, 1648581351}, new object[]{"main", "Main", "Main.hx"}, new int[]{1981972957}, new double[]{((double) (112) )}));
			global::haxe.Log.trace.__hx_invoke2_o(default(double), abstractMap.exists(global::haxe.lang.Runtime.toString(global::_Main.Foo_Impl_._new<object>(((object) ("Foo<String>1") )))), default(double), new global::haxe.lang.DynamicObject(new int[]{302979532, 1547539107, 1648581351}, new object[]{"main", "Main", "Main.hx"}, new int[]{1981972957}, new double[]{((double) (114) )}));
			global::haxe.Log.trace.__hx_invoke2_o(default(double), global::haxe.lang.Runtime.toString((abstractMap.@get(global::haxe.lang.Runtime.toString(global::_Main.Foo_Impl_._new<object>(((object) ("Foo<String>1") ))))).toDynamic()), default(double), new global::haxe.lang.DynamicObject(new int[]{302979532, 1547539107, 1648581351}, new object[]{"main", "Main", "Main.hx"}, new int[]{1981972957}, new double[]{((double) (115) )}));
			global::haxe.Log.trace.__hx_invoke2_o(default(double), abstractMap.exists(global::haxe.lang.Runtime.toString(global::_Main.Foo_Impl_._new<object>(((object) ("Foo<String>2") )))), default(double), new global::haxe.lang.DynamicObject(new int[]{302979532, 1547539107, 1648581351}, new object[]{"main", "Main", "Main.hx"}, new int[]{1981972957}, new double[]{((double) (117) )}));
			global::haxe.Log.trace.__hx_invoke2_o(default(double), global::haxe.lang.Runtime.toString((abstractMap.@get(global::haxe.lang.Runtime.toString(global::_Main.Foo_Impl_._new<object>(((object) ("Foo<String>2") ))))).toDynamic()), default(double), new global::haxe.lang.DynamicObject(new int[]{302979532, 1547539107, 1648581351}, new object[]{"main", "Main", "Main.hx"}, new int[]{1981972957}, new double[]{((double) (118) )}));
		}
	}