fix nim-lang#19546 Missing compiler error for array in type definition (also apply to seq, set)

Author: bung87

compiler/semstmts.nim

@@ -404,6 +404,10 @@ proc hasEmpty(typ: PType): bool =
     for s in typ.sons:
       result = result or hasEmpty(s)
 
+proc hasNone(typ: PType): bool =
+  if typ.kind in {tySequence, tyArray, tySet}:
+    result = typ.lastSon.kind == tyNone
+
 proc hasUnresolvedParams(n: PNode; flags: TExprFlags): bool =
   result = tfUnresolved in n.typ.flags
   when false:
@@ -1442,31 +1446,42 @@ proc typeSectionRightSidePass(c: PContext, n: PNode) =
       obj.typ = objTy
       objTy.sym = obj
 
-proc checkForMetaFields(c: PContext; n: PNode) =
-  proc checkMeta(c: PContext; n: PNode; t: PType) =
+proc checkForMetaFields(c: PContext; n: PNode; hasError: var bool) =
+  proc checkMeta(c: PContext; n: PNode; t: PType; hasError: var bool) =
     if t != nil and t.isMetaType and tfGenericTypeParam notin t.flags:
       if t.kind == tyBuiltInTypeClass and t.len == 1 and t[0].kind == tyProc:
+        hasError = true
         localError(c.config, n.info, ("'$1' is not a concrete type; " &
           "for a callback without parameters use 'proc()'") % t.typeToString)
       else:
+        hasError = true
         localError(c.config, n.info, errTIsNotAConcreteType % t.typeToString)
 
   if n.isNil: return
   case n.kind
   of nkRecList, nkRecCase:
-    for s in n: checkForMetaFields(c, s)
+    for s in n: checkForMetaFields(c, s, hasError)
   of nkOfBranch, nkElse:
-    checkForMetaFields(c, n.lastSon)
+    checkForMetaFields(c, n.lastSon, hasError)
   of nkSym:
     let t = n.sym.typ
     case t.kind
     of tySequence, tySet, tyArray, tyOpenArray, tyVar, tyLent, tyPtr, tyRef,
        tyProc, tyGenericInvocation, tyGenericInst, tyAlias, tySink, tyOwned:
       let start = ord(t.kind in {tyGenericInvocation, tyGenericInst})
+      if t.hasNone():
+        hasError = true
+        case t.kind
+        of tyArray:
+          localError(c.config, n.info, errArrayExpectsTwoTypeParams)
+        of tySequence, tySet:
+          localError(c.config, n.info, "$1 expects one type parameter" % toHumanStr(t.kind))
+        else:
+          discard
       for i in start..<t.len:
-        checkMeta(c, n, t[i])
+        checkMeta(c, n, t[i], hasError)
     else:
-      checkMeta(c, n, t)
+      checkMeta(c, n, t, hasError)
   else:
     internalAssert c.config, false
 
@@ -1501,10 +1516,11 @@ proc typeSectionFinalPass(c: PContext, n: PNode) =
               assert s.typ != nil
               assignType(s.typ, t)
               s.typ.itemId = t.itemId     # same id
-        checkConstructedType(c.config, s.info, s.typ)
+        var hasError = false
         if s.typ.kind in {tyObject, tyTuple} and not s.typ.n.isNil:
-          checkForMetaFields(c, s.typ.n)
-
+          checkForMetaFields(c, s.typ.n, hasError)
+        if not hasError:
+          checkConstructedType(c.config, s.info, s.typ)
         # fix bug #5170, bug #17162, bug #15526: ensure locally scoped types get a unique name:
         if s.typ.kind in {tyEnum, tyRef, tyObject} and not isTopLevel(c):
           incl(s.flags, sfGenSym)

compiler/semtypinst.nim

@@ -23,6 +23,10 @@ proc checkPartialConstructedType(conf: ConfigRef; info: TLineInfo, t: PType) =
   if t.kind in {tyVar, tyLent} and t[0].kind in {tyVar, tyLent}:
     localError(conf, info, "type 'var var' is not allowed")
 
+proc hasNone(typ: PType): bool =
+  if typ.kind in {tySequence, tyArray, tySet}:
+    result = typ.lastSon.kind == tyNone
+
 proc checkConstructedType*(conf: ConfigRef; info: TLineInfo, typ: PType) =
   var t = typ.skipTypes({tyDistinct})
   if t.kind in tyTypeClasses: discard

tests/errmsgs/t19546.nim

@@ -0,0 +1,20 @@
+discard """
+  cmd: "nim check --hints:off $file"
+  errormsg: ""
+  nimout: '''
+t19546.nim(12, 5) Error: array expects two type parameters
+t19546.nim(16, 5) Error: sequence expects one type parameter
+t19546.nim(20, 5) Error: set expects one type parameter
+'''
+"""
+type
+  ExampleObj1 = object
+    arr: array
+
+type
+  ExampleObj2 = object
+    arr: seq
+
+type
+  ExampleObj3 = object
+    arr: set