fix assignment to converted concept type (nim-lang#15051)

* fix assignment to converted concept type

* check for resolved concepts

* add extra test

compiler/types.nim

@@ -1070,7 +1070,11 @@ proc sameTypeAux(x, y: PType, c: var TSameTypeClosure): bool =
 
   if x == y: return true
   var a = skipTypes(x, {tyGenericInst, tyAlias})
+  while a.kind == tyUserTypeClass and tfResolved in a.flags:
+    a = skipTypes(a[^1], {tyGenericInst, tyAlias})
   var b = skipTypes(y, {tyGenericInst, tyAlias})
+  while b.kind == tyUserTypeClass and tfResolved in b.flags:
+    b = skipTypes(b[^1], {tyGenericInst, tyAlias})
   assert(a != nil)
   assert(b != nil)
   if a.kind != b.kind:

tests/concepts/tusertypeclasses2.nim

@@ -1,24 +1,44 @@
-type
-  hasFieldX = concept z
-    z.x is int
+block:
+  type
+    hasFieldX = concept z
+      z.x is int
 
-  obj_x = object
-    x: int
+    obj_x = object
+      x: int
 
-  ref_obj_x = ref object
-    x: int
+    ref_obj_x = ref object
+      x: int
 
-  ref_to_obj_x = ref obj_x
+    ref_to_obj_x = ref obj_x
 
-  p_o_x = ptr obj_x
-  v_o_x = var obj_x
+    p_o_x = ptr obj_x
+    v_o_x = var obj_x
 
-template check(x) =
-  static: assert(x)
+  template check(x) =
+    static: assert(x)
 
-check obj_x is hasFieldX
-check ref_obj_x is hasFieldX
-check ref_to_obj_x is hasFieldX
-check p_o_x is hasFieldX
-check v_o_x is hasFieldX
+  check obj_x is hasFieldX
+  check ref_obj_x is hasFieldX
+  check ref_to_obj_x is hasFieldX
+  check p_o_x is hasFieldX
+  check v_o_x is hasFieldX
 
+block:
+  type
+    Foo = concept x
+      x.isFoo
+    Bar = distinct float
+  template isFoo(x: Bar): untyped = true
+  proc foo(x: var Foo) =
+    float(x) = 1.0
+  proc foo2(x: var Bar) =
+    float(x) = 1.0
+  proc foo3(x: var (Bar|SomeNumber)) =
+    float(x) = 1.0
+  proc foo4(x: var any) =
+    float(x) = 1.0
+  var x: Bar
+  foo(x)
+  foo2(x)
+  foo3(x)
+  foo4(x)