fixes #20048; fixes #15746; don't sink object fields if it's of openarray type

compiler/injectdestructors.nim

@@ -872,7 +872,8 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
       for i in 1..<n.len:
         if n[i].kind == nkExprColonExpr:
           let field = lookupFieldAgain(t, n[i][0].sym)
-          if field != nil and sfCursor in field.flags:
+          if field != nil and (sfCursor in field.flags or field.typ.kind in {tyOpenArray, tyVarargs}):
+            # don't sink fields with openarray types
             result[i][1] = p(n[i][1], c, s, normal)
           else:
             result[i][1] = p(n[i][1], c, s, m)

tests/views/tviews1.nim

@@ -124,3 +124,13 @@ proc bug22597 = # bug #22597
   doAssert i == 1
 
 bug22597()
+
+block: # bug #20048
+  type
+    Test = object
+      tokens: openArray[string]
+
+  func init(Self: typedesc[Test], tokens: openArray[string]): Self = Self(tokens: tokens)
+
+  let data = Test.init(["123"])
+  doAssert @(data.tokens) == @["123"] 

tests/views/tviews2.nim

@@ -58,6 +58,18 @@ block: # bug #16671
 
     f()
 
+block: # bug #15746
+  type
+    Reader = object
+      data: openArray[char]
+      current: int
+
+  proc initReader(data: openArray[char], offset = 0): Reader =
+    result = Reader(data: data, current: offset)
+
+  let s = "\x01\x00\x00\x00"
+  doAssert initReader(s).data[0].int == 1
+
 block:
   proc foo(x: openArray[char]) =
     discard x