Fix #11923 (#19427)

* Apply commit 5da931f that was never merged (was part of a bigger PR). Should fix issue #11932

* add a generic object for custom pragma

Author: Clonkk

lib/core/macros.nim

@@ -1523,7 +1523,12 @@ proc customPragmaNode(n: NimNode): NimNode =
   if n.kind in {nnkDotExpr, nnkCheckedFieldExpr}:
     let name = $(if n.kind == nnkCheckedFieldExpr: n[0][1] else: n[1])
     let typInst = getTypeInst(if n.kind == nnkCheckedFieldExpr or n[0].kind == nnkHiddenDeref: n[0][0] else: n[0])
-    var typDef = getImpl(if typInst.kind == nnkVarTy: typInst[0] else: typInst)
+    var typDef = getImpl(
+      if typInst.kind == nnkVarTy or
+         typInst.kind == nnkBracketExpr:
+        typInst[0]
+      else: typInst
+    )
     while typDef != nil:
       typDef.expectKind(nnkTypeDef)
       let typ = typDef[2]

tests/pragmas/tcustom_pragma.nim

@@ -17,11 +17,21 @@ block:
     MyObj = object
       myField1, myField2 {.myAttr: "hi".}: int
 
+    MyGenericObj[T] = object
+      myField1, myField2 {.myAttr: "hi".}: int
+
+
   var o: MyObj
   static:
     doAssert o.myField2.hasCustomPragma(myAttr)
     doAssert(not o.myField1.hasCustomPragma(myAttr))
 
+  var ogen: MyGenericObj[int]
+  static:
+    doAssert ogen.myField2.hasCustomPragma(myAttr)
+    doAssert(not ogen.myField1.hasCustomPragma(myAttr))
+
+
 import custom_pragma
 block: # A bit more advanced case
   type