diff --git a/src/testdir/test_vim9_class.vim b/src/testdir/test_vim9_class.vim
index be4eb2e..1796f5f 100644
--- a/src/testdir/test_vim9_class.vim
+++ b/src/testdir/test_vim9_class.vim
@@ -8,56 +8,56 @@
       class NotWorking
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1316:')
+  v9.CheckSourceFailure(lines, 'E1316:')
 
   lines =<< trim END
       vim9script
       class notWorking
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1314:')
+  v9.CheckSourceFailure(lines, 'E1314:')
 
   lines =<< trim END
       vim9script
       class Not@working
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1315:')
+  v9.CheckSourceFailure(lines, 'E1315:')
 
   lines =<< trim END
       vim9script
       abstract noclass Something
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E475:')
+  v9.CheckSourceFailure(lines, 'E475:')
 
   lines =<< trim END
       vim9script
       abstract classy Something
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E475:')
+  v9.CheckSourceFailure(lines, 'E475:')
 
   lines =<< trim END
       vim9script
       class Something
       endcl
   END
-  v9.CheckScriptFailure(lines, 'E1065:')
+  v9.CheckSourceFailure(lines, 'E1065:')
 
   lines =<< trim END
       vim9script
       class Something
       endclass school's out
   END
-  v9.CheckScriptFailure(lines, 'E488:')
+  v9.CheckSourceFailure(lines, 'E488:')
 
   lines =<< trim END
       vim9script
       class Something
       endclass | echo 'done'
   END
-  v9.CheckScriptFailure(lines, 'E488:')
+  v9.CheckSourceFailure(lines, 'E488:')
 
   lines =<< trim END
       vim9script
@@ -65,7 +65,7 @@
         this
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1317:')
+  v9.CheckSourceFailure(lines, 'E1317:')
 
   lines =<< trim END
       vim9script
@@ -73,7 +73,7 @@
         this.
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1317:')
+  v9.CheckSourceFailure(lines, 'E1317:')
 
   lines =<< trim END
       vim9script
@@ -81,7 +81,7 @@
         this .count
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1317:')
+  v9.CheckSourceFailure(lines, 'E1317:')
 
   lines =<< trim END
       vim9script
@@ -89,7 +89,7 @@
         this. count
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1317:')
+  v9.CheckSourceFailure(lines, 'E1317:')
 
   lines =<< trim END
       vim9script
@@ -98,7 +98,7 @@
         that.count
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1318: Not a valid command in a class: that.count')
+  v9.CheckSourceFailure(lines, 'E1318: Not a valid command in a class: that.count')
 
   lines =<< trim END
       vim9script
@@ -106,7 +106,7 @@
         this.count
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1022:')
+  v9.CheckSourceFailure(lines, 'E1022:')
 
   lines =<< trim END
       vim9script
@@ -117,7 +117,7 @@
       endclass
       var obj = Something.new()
   END
-  v9.CheckScriptFailure(lines, 'E1089:')
+  v9.CheckSourceFailure(lines, 'E1089:')
 
   lines =<< trim END
       vim9script
@@ -125,7 +125,7 @@
         this.count : number
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1059:')
+  v9.CheckSourceFailure(lines, 'E1059:')
 
   lines =<< trim END
       vim9script
@@ -133,7 +133,7 @@
         this.count:number
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1069:')
+  v9.CheckSourceFailure(lines, 'E1069:')
 
   # Test for unsupported comment specifier
   lines =<< trim END
@@ -143,7 +143,7 @@
       #{
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1170:')
+  v9.CheckSourceFailure(lines, 'E1170:')
 
   lines =<< trim END
       vim9script
@@ -171,7 +171,7 @@
       assert_equal('class<TextPosition>', typename(TextPosition))
       assert_equal('object<TextPosition>', typename(pos))
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # When referencing object methods, space cannot be used after a "."
   lines =<< trim END
@@ -184,7 +184,7 @@
     var a = A.new()
     var v = a. Foo()
   END
-  v9.CheckScriptFailure(lines, 'E1202:')
+  v9.CheckSourceFailure(lines, 'E1202:')
 
   # Using an object without specifying a method or a member variable
   lines =<< trim END
@@ -197,7 +197,7 @@
     var a = A.new()
     var v = a.
   END
-  v9.CheckScriptFailure(lines, 'E15:')
+  v9.CheckSourceFailure(lines, 'E15:')
 
   # Error when parsing the arguments of an object method.
   lines =<< trim END
@@ -209,7 +209,7 @@
     var a = A.new()
     var v = a.Foo(,)
   END
-  v9.CheckScriptFailure(lines, 'E15:')
+  v9.CheckSourceFailure(lines, 'E15:')
 
   lines =<< trim END
   vim9script
@@ -220,7 +220,7 @@
   endclass
   var a = A.new()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_class_defined_twice()
@@ -232,7 +232,7 @@
       class There
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1041: Redefining script item: "There"')
+  v9.CheckSourceFailure(lines, 'E1041: Redefining script item: "There"')
 
   # one class, reload same script twice is OK
   lines =<< trim END
@@ -259,7 +259,7 @@
       var buffers = BufferList.new()
       echo buffers.Current()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_using_null_class()
@@ -276,7 +276,7 @@
         this.member = 'text'
       endinterface
   END
-  v9.CheckScriptFailure(lines, 'E476: Invalid command: endinterface, expected endclass')
+  v9.CheckSourceFailure(lines, 'E476: Invalid command: endinterface, expected endclass')
 
   lines =<< trim END
       vim9script
@@ -284,7 +284,7 @@
         this.member: string
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E476: Invalid command: endclass, expected endinterface')
+  v9.CheckSourceFailure(lines, 'E476: Invalid command: endclass, expected endinterface')
 enddef
 
 def Test_object_not_set()
@@ -299,7 +299,7 @@
       var db = {'xyz': 789}
       echo db[state.value]
   END
-  v9.CheckScriptFailure(lines, 'E1360:')
+  v9.CheckSourceFailure(lines, 'E1360:')
 
   lines =<< trim END
       vim9script
@@ -317,7 +317,7 @@
       enddef
       Func()
   END
-  v9.CheckScriptFailure(lines, 'E1360:')
+  v9.CheckSourceFailure(lines, 'E1360:')
 
   lines =<< trim END
       vim9script
@@ -337,7 +337,7 @@
       var bg: Background           # UNINITIALIZED
       echo Colorscheme.new(bg).GetBackground()
   END
-  v9.CheckScriptFailure(lines, 'E1360:')
+  v9.CheckSourceFailure(lines, 'E1360:')
 
   # TODO: this should not give an error but be handled at runtime
   lines =<< trim END
@@ -356,7 +356,7 @@
       enddef
       Func()
   END
-  v9.CheckScriptFailure(lines, 'E1363:')
+  v9.CheckSourceFailure(lines, 'E1363:')
 enddef
 
 def Test_null_object_assign_compare()
@@ -396,7 +396,7 @@
     o2 = null_object
     assert_true(o2 == null)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_class_member_initializer()
@@ -432,7 +432,7 @@
             '\d\+ RETURN object.*',
             instr)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_member_any_used_as_object()
@@ -456,7 +456,7 @@
       F(outer_obj)
       assert_equal(1, inner_obj.value)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -482,7 +482,51 @@
 
       Test_assign_to_nested_typed_member()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
+
+  # Try modifying a private variable using an "any" object
+  lines =<< trim END
+    vim9script
+
+    class Inner
+      this._value: string = ''
+    endclass
+
+    class Outer
+      this.inner: any
+    endclass
+
+    def F(outer: Outer)
+      outer.inner._value = 'b'
+    enddef
+
+    var inner_obj = Inner.new('a')
+    var outer_obj = Outer.new(inner_obj)
+    F(outer_obj)
+  END
+  v9.CheckSourceFailure(lines, 'E1333: Cannot access private member: _value')
+
+  # Try modifying a non-existing variable using an "any" object
+  lines =<< trim END
+    vim9script
+
+    class Inner
+      this.value: string = ''
+    endclass
+
+    class Outer
+      this.inner: any
+    endclass
+
+    def F(outer: Outer)
+      outer.inner.someval = 'b'
+    enddef
+
+    var inner_obj = Inner.new('a')
+    var outer_obj = Outer.new(inner_obj)
+    F(outer_obj)
+  END
+  v9.CheckSourceFailure(lines, 'E1326: Member not found on object "Inner": someval')
 enddef
 
 def Test_assignment_with_operator()
@@ -508,7 +552,7 @@
       AddToFoo(f)
       assert_equal(23, f.x)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # do the same thing, but through an interface
   lines =<< trim END
@@ -538,7 +582,7 @@
       AddToFoo(f)
       assert_equal(23, f.x)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_list_of_objects()
@@ -559,7 +603,7 @@
       var l: list<Foo> = [Foo.new()]
       ProcessList(l)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_expr_after_using_object()
@@ -578,7 +622,7 @@
 
       Foo()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_class_default_new()
@@ -606,7 +650,7 @@
       assert_equal(1, pos.lnum)
       assert_equal(33, pos.col)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -629,7 +673,7 @@
       assert_equal(4, chris.age)
       assert_equal("none", chris.education)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -644,7 +688,7 @@
 
       var missing = Person.new()
   END
-  v9.CheckScriptFailure(lines, 'E119:')
+  v9.CheckSourceFailure(lines, 'E119:')
 enddef
 
 
@@ -677,7 +721,7 @@
 
       Check()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -699,7 +743,7 @@
 
       Check()
   END
-  v9.CheckScriptFailure(lines, 'E1013:')
+  v9.CheckSourceFailure(lines, 'E1013:')
 
   lines =<< trim END
       vim9script
@@ -721,7 +765,7 @@
 
       Check()
   END
-  v9.CheckScriptFailure(lines, 'E1013:')
+  v9.CheckSourceFailure(lines, 'E1013:')
 enddef
 
 def Test_class_object_member_inits()
@@ -738,7 +782,7 @@
       assert_equal(1, pos.col)
       assert_equal(2, pos.addcol)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -747,7 +791,7 @@
         this.col = 1
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1022:')
+  v9.CheckSourceFailure(lines, 'E1022:')
 
   # If the type is not specified for a member, then it should be set during
   # object creation and not when defining the class.
@@ -770,7 +814,7 @@
       var a = A.new()
       assert_equal(init_count, 2)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Test for initializing an object member with an unknown variable/type
   lines =<< trim END
@@ -780,10 +824,11 @@
     endclass
     var a = A.new()
   END
-  v9.CheckScriptFailure(lines, 'E1001:')
+  v9.CheckSourceFailure(lines, 'E1001:')
 enddef
 
-def Test_class_object_member_access()
+" Test for instance variable access
+def Test_instance_variable_access()
   var lines =<< trim END
       vim9script
       class Triple
@@ -807,9 +852,9 @@
       trip.three = 33
       assert_equal(33, trip.three)
 
-      assert_fails('trip.four = 4', 'E1334')
+      assert_fails('trip.four = 4', 'E1326')
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Test for a public member variable name beginning with an underscore
   lines =<< trim END
@@ -818,7 +863,7 @@
       public this._val = 10
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1332:')
+  v9.CheckSourceFailure(lines, 'E1332:')
 
   lines =<< trim END
       vim9script
@@ -854,7 +899,7 @@
       enddef
       CheckCar()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -870,7 +915,7 @@
       var c = MyCar.new("abc")
       var c = MyCar.new("def")
   END
-  v9.CheckScriptFailure(lines, 'E1041:')
+  v9.CheckSourceFailure(lines, 'E1041:')
 
   lines =<< trim END
       vim9script
@@ -896,7 +941,7 @@
             .Add(2)
             .x
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Test for "public" cannot be abbreviated
   lines =<< trim END
@@ -905,7 +950,7 @@
       pub this.val = 1
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1065:')
+  v9.CheckSourceFailure(lines, 'E1065:')
 
   # Test for "public" keyword must be followed by "this" or "static".
   lines =<< trim END
@@ -914,25 +959,53 @@
       public val = 1
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1331:')
+  v9.CheckSourceFailure(lines, 'E1331:')
 
-  # Test for "static" cannot be abbreviated
+  # Modify a instance variable using the class name in the script context
   lines =<< trim END
     vim9script
-    class Something
-      stat this.val = 1
+    class A
+      public this.val = 1
     endclass
+    A.val = 1
   END
-  v9.CheckScriptFailure(lines, 'E1065:')
+  v9.CheckSourceFailure(lines, 'E1376: Object member "val" accessible only using class "A" object')
 
-  # Test for "static" cannot be followed by "this".
+  # Read a instance variable using the class name in the script context
   lines =<< trim END
     vim9script
-    class Something
-      static this.val = 1
+    class A
+      public this.val = 1
     endclass
+    var i = A.val
   END
-  v9.CheckScriptFailure(lines, 'E1368: Static cannot be followed by "this" in a member name')
+  v9.CheckSourceFailure(lines, 'E1376: Object member "val" accessible only using class "A" object')
+
+  # Modify a instance variable using the class name in a def function
+  lines =<< trim END
+    vim9script
+    class A
+      public this.val = 1
+    endclass
+    def T()
+      A.val = 1
+    enddef
+    T()
+  END
+  v9.CheckSourceFailure(lines, 'E1376: Object member "val" accessible only using class "A" object')
+
+  # Read a instance variable using the class name in a def function
+  lines =<< trim END
+    vim9script
+    class A
+      public this.val = 1
+    endclass
+    def T()
+      var i = A.val
+    enddef
+    T()
+  END
+  v9.CheckSourceFailure(lines, 'E1376: Object member "val" accessible only using class "A" object')
 
   # Access from child class extending a class:
   lines =<< trim END
@@ -941,10 +1014,6 @@
         this.ro_obj_var = 10
         public this.rw_obj_var = 20
         this._priv_obj_var = 30
-
-        static ro_class_var = 40
-        public static rw_class_var = 50
-        static _priv_class_var = 60
       endclass
 
       class B extends A
@@ -956,19 +1025,89 @@
           this.rw_obj_var = 0
           x = this._priv_obj_var
           this._priv_obj_var = 0
+        enddef
+      endclass
 
-          x = ro_class_var
-          ro_class_var = 0
-          x = rw_class_var
-          rw_class_var = 0
-          x = _priv_class_var
-          _priv_class_var = 0
+      var b = B.new()
+      b.Foo()
+  END
+  v9.CheckSourceSuccess(lines)
+enddef
 
-          x = A.ro_class_var
-          A.ro_class_var = 0
-          x = A.rw_class_var
-          A.rw_class_var = 0
-          x = A._priv_class_var
+" Test for class variable access
+def Test_class_variable_access()
+  # Test for "static" cannot be abbreviated
+  var lines =<< trim END
+    vim9script
+    class Something
+      stat this.val = 1
+    endclass
+  END
+  v9.CheckSourceFailure(lines, 'E1065:')
+
+  # Test for "static" cannot be followed by "this".
+  lines =<< trim END
+    vim9script
+    class Something
+      static this.val = 1
+    endclass
+  END
+  v9.CheckSourceFailure(lines, 'E1368: Static cannot be followed by "this" in a member name')
+
+  # Test for "static" cannot be followed by "public".
+  lines =<< trim END
+    vim9script
+    class Something
+      static public val = 1
+    endclass
+  END
+  v9.CheckSourceFailure(lines, 'E1022: Type or initialization required')
+
+  # A readonly class variable cannot be modified from a child class
+  lines =<< trim END
+      vim9script
+      class A
+        static ro_class_var = 40
+      endclass
+
+      class B extends A
+        def Foo()
+          A.ro_class_var = 50
+        enddef
+      endclass
+
+      var b = B.new()
+      b.Foo()
+  END
+  v9.CheckSourceFailure(lines, 'E46: Cannot change read-only variable "ro_class_var"')
+
+  # A private class variable cannot be accessed from a child class
+  lines =<< trim END
+      vim9script
+      class A
+        static _priv_class_var = 60
+      endclass
+
+      class B extends A
+        def Foo()
+          var i = A._priv_class_var
+        enddef
+      endclass
+
+      var b = B.new()
+      b.Foo()
+  END
+  v9.CheckSourceFailure(lines, 'E1333: Cannot access private member: _priv_class_var')
+
+  # A private class variable cannot be modified from a child class
+  lines =<< trim END
+      vim9script
+      class A
+        static _priv_class_var = 60
+      endclass
+
+      class B extends A
+        def Foo()
           A._priv_class_var = 0
         enddef
       endclass
@@ -976,7 +1115,37 @@
       var b = B.new()
       b.Foo()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceFailure(lines, 'E1333: Cannot access private member: _priv_class_var')
+
+  # Access from child class extending a class and from script context
+  lines =<< trim END
+      vim9script
+      class A
+        static ro_class_var = 10
+        public static rw_class_var = 20
+        static _priv_class_var = 30
+      endclass
+
+      class B extends A
+        def Foo()
+          var x: number
+          x = A.ro_class_var
+          assert_equal(10, x)
+          x = A.rw_class_var
+          assert_equal(25, x)
+          A.rw_class_var = 20
+          assert_equal(20, A.rw_class_var)
+        enddef
+      endclass
+
+      assert_equal(10, A.ro_class_var)
+      assert_equal(20, A.rw_class_var)
+      A.rw_class_var = 25
+      assert_equal(25, A.rw_class_var)
+      var b = B.new()
+      b.Foo()
+  END
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_class_object_compare()
@@ -1005,8 +1174,8 @@
       assert_notequal(i1, io2)
   END
 
-  v9.CheckScriptSuccess(class_lines + test_lines)
-  v9.CheckScriptSuccess(
+  v9.CheckSourceSuccess(class_lines + test_lines)
+  v9.CheckSourceSuccess(
       class_lines + ['def Test()'] + test_lines + ['enddef', 'Test()'])
 
   for op in ['>', '>=', '<', '<=', '=~', '!~']
@@ -1015,8 +1184,8 @@
           'var i2 = Item.new()',
           'echo i1 ' .. op .. ' i2',
           ]
-    v9.CheckScriptFailure(class_lines + op_lines, 'E1153: Invalid operation for object')
-    v9.CheckScriptFailure(class_lines
+    v9.CheckSourceFailure(class_lines + op_lines, 'E1153: Invalid operation for object')
+    v9.CheckSourceFailure(class_lines
           + ['def Test()'] + op_lines + ['enddef', 'Test()'], 'E1153: Invalid operation for object')
   endfor
 enddef
@@ -1042,7 +1211,7 @@
 
       t = m
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -1056,7 +1225,7 @@
 
       var o: One = Two.new()
   END
-  v9.CheckScriptFailure(lines, 'E1012: Type mismatch; expected object<One> but got object<Two>')
+  v9.CheckSourceFailure(lines, 'E1012: Type mismatch; expected object<One> but got object<Two>')
 
   lines =<< trim END
       vim9script
@@ -1074,7 +1243,7 @@
       var o: One = Two.new(5)
       assert_equal(5, o.GetMember())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -1094,7 +1263,7 @@
 
       echo Fn(Num.new(4))
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_class_member()
@@ -1116,7 +1285,7 @@
       assert_equal(0, TextPos.counter)
       TextPos.AddToCounter(3)
       assert_equal(3, TextPos.counter)
-      assert_fails('echo TextPos.noSuchMember', 'E1338:')
+      assert_fails('echo TextPos.noSuchMember', 'E1337:')
 
       def GetCounter(): number
         return TextPos.counter
@@ -1136,7 +1305,7 @@
       TextPos.anybody += 5
       assert_equal(17, TextPos.anybody)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # example in the help
   lines =<< trim END
@@ -1155,7 +1324,7 @@
         var to7 = OtherThing.new(7)
         assert_equal(10, OtherThing.totalSize)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # using static class member twice
   lines =<< trim END
@@ -1172,7 +1341,7 @@
       assert_equal('some text', HTML.MacroSubstitute('some text'))
       assert_equal('some text', HTML.MacroSubstitute('some text'))
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # access private member in lambda
   lines =<< trim END
@@ -1190,7 +1359,7 @@
       var foo = Foo.new()
       assert_equal(5, foo.Add(5))
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # access private member in lambda body
   lines =<< trim END
@@ -1211,7 +1380,7 @@
       var foo = Foo.new()
       assert_equal(13, foo.Add(7))
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # check shadowing
   lines =<< trim END
@@ -1227,7 +1396,7 @@
       var s = Some.new()
       s.Method(7)
   END
-  v9.CheckScriptFailure(lines, 'E1340: Argument already declared in the class: count')
+  v9.CheckSourceFailure(lines, 'E1340: Argument already declared in the class: count')
 
   lines =<< trim END
       vim9script
@@ -1243,7 +1412,7 @@
       var s = Some.new()
       s.Method(7)
   END
-  v9.CheckScriptFailure(lines, 'E1341: Variable already declared in the class: count')
+  v9.CheckSourceFailure(lines, 'E1341: Variable already declared in the class: count')
 
   # Test for using an invalid type for a member variable
   lines =<< trim END
@@ -1252,7 +1421,7 @@
       this.val: xxx
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1010:')
+  v9.CheckSourceFailure(lines, 'E1010:')
 
   # Test for setting a member on a null object
   lines =<< trim END
@@ -1267,7 +1436,7 @@
     enddef
     F()
   END
-  v9.CheckScriptFailure(lines, 'E1360: Using a null object')
+  v9.CheckSourceFailure(lines, 'E1360: Using a null object')
 
   # Test for accessing a member on a null object
   lines =<< trim END
@@ -1282,7 +1451,7 @@
     enddef
     F()
   END
-  v9.CheckScriptFailure(lines, 'E1360: Using a null object')
+  v9.CheckSourceFailure(lines, 'E1360: Using a null object')
 
   # Test for setting a member on a null object, at script level
   lines =<< trim END
@@ -1295,7 +1464,7 @@
     obj.val = ""
   END
   # FIXME(in source): this should give E1360 as well!
-  v9.CheckScriptFailure(lines, 'E1012: Type mismatch; expected object<A> but got string')
+  v9.CheckSourceFailure(lines, 'E1012: Type mismatch; expected object<A> but got string')
 
   # Test for accessing a member on a null object, at script level
   lines =<< trim END
@@ -1307,7 +1476,7 @@
     var obj: A
     echo obj.val
   END
-  v9.CheckScriptFailure(lines, 'E1360: Using a null object')
+  v9.CheckSourceFailure(lines, 'E1360: Using a null object')
 
   # Test for no space before or after the '=' when initializing a member
   # variable
@@ -1317,14 +1486,14 @@
       this.val: number= 10
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1004:')
+  v9.CheckSourceFailure(lines, 'E1004:')
   lines =<< trim END
     vim9script
     class A
       this.val: number =10
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1004:')
+  v9.CheckSourceFailure(lines, 'E1004:')
 
   # Access a non-existing member
   lines =<< trim END
@@ -1334,7 +1503,7 @@
     var a = A.new()
     var v = a.bar
   END
-  v9.CheckScriptFailure(lines, 'E1326:')
+  v9.CheckSourceFailure(lines, 'E1326: Member not found on object "A": bar')
 enddef
 
 func Test_class_garbagecollect()
@@ -1351,7 +1520,7 @@
       call test_garbagecollect_now()
       echo Point.pl Point.pd
   END
-  call v9.CheckScriptSuccess(lines)
+  call v9.CheckSourceSuccess(lines)
 
   let lines =<< trim END
       vim9script
@@ -1378,7 +1547,7 @@
       view = MyView.new()
       test_garbagecollect_now()
   END
-  call v9.CheckScriptSuccess(lines)
+  call v9.CheckSourceSuccess(lines)
 endfunc
 
 " Test interface garbage collection
@@ -1432,7 +1601,7 @@
     assert_equal(60, A.ClassFoo())
     assert_equal(150, o.ObjFoo())
   END
-  call v9.CheckScriptSuccess(lines)
+  call v9.CheckSourceSuccess(lines)
 endfunc
 
 def Test_class_function()
@@ -1458,7 +1627,7 @@
       var v2 = Value.new(7)
       assert_equal(2, Value.GetCount())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Test for cleaning up after a class definition failure when using class
   # functions.
@@ -1470,7 +1639,7 @@
       aaa
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1318:')
+  v9.CheckSourceFailure(lines, 'E1318:')
 enddef
 
 def Test_class_defcompile()
@@ -1485,7 +1654,7 @@
 
       defcompile C.Fo
   END
-  v9.CheckScriptFailure(lines, 'E1012: Type mismatch; expected string but got number')
+  v9.CheckSourceFailure(lines, 'E1012: Type mismatch; expected string but got number')
 
   lines =<< trim END
       vim9script
@@ -1498,7 +1667,7 @@
 
       defcompile C.Fc
   END
-  v9.CheckScriptFailure(lines, 'E1012: Type mismatch; expected number but got string')
+  v9.CheckSourceFailure(lines, 'E1012: Type mismatch; expected number but got string')
 
   lines =<< trim END
       vim9script
@@ -1510,14 +1679,14 @@
 
       defcompile C.new
   END
-  v9.CheckScriptFailure(lines, 'E1370: Cannot define a "new" function as static')
+  v9.CheckSourceFailure(lines, 'E1370: Cannot define a "new" function as static')
 
   # Trying to compile a function using a non-existing class variable
   lines =<< trim END
     vim9script
     defcompile x.Foo()
   END
-  v9.CheckScriptFailure(lines, 'E475:')
+  v9.CheckSourceFailure(lines, 'E475:')
 
   # Trying to compile a function using a variable which is not a class
   lines =<< trim END
@@ -1525,7 +1694,7 @@
     var x: number
     defcompile x.Foo()
   END
-  v9.CheckScriptFailure(lines, 'E475:')
+  v9.CheckSourceFailure(lines, 'E475:')
 
   # Trying to compile a function without specifying the name
   lines =<< trim END
@@ -1534,7 +1703,7 @@
     endclass
     defcompile A.
   END
-  v9.CheckScriptFailure(lines, 'E475:')
+  v9.CheckSourceFailure(lines, 'E475:')
 
   # Trying to compile a non-existing class object member function
   lines =<< trim END
@@ -1544,7 +1713,7 @@
     var a = A.new()
     defcompile a.Foo()
   END
-  v9.CheckScriptFailureList(lines, ['E1334:', 'E475:'])
+  v9.CheckSourceFailureList(lines, ['E1326:', 'E475:'])
 enddef
 
 def Test_class_object_to_string()
@@ -1560,7 +1729,7 @@
       var pos = TextPosition.new()
       assert_equal("object of TextPosition {lnum: 1, col: 22}", string(pos))
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_interface_basics()
@@ -1572,14 +1741,14 @@
         def GetCount(): number
       endinterface
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       interface SomethingWrong
         static count = 7
       endinterface
   END
-  v9.CheckScriptFailure(lines, 'E1342:')
+  v9.CheckSourceFailure(lines, 'E1342:')
 
   lines =<< trim END
       vim9script
@@ -1589,7 +1758,7 @@
         def Method(count: number)
       endinterface
   END
-  v9.CheckScriptFailure(lines, 'E1340: Argument already declared in the class: count', 5)
+  v9.CheckSourceFailure(lines, 'E1340: Argument already declared in the class: count', 5)
 
   lines =<< trim END
       vim9script
@@ -1601,7 +1770,7 @@
   END
   # The argument name and the object member name are the same, but this is not a
   # problem because object members are always accessed with the "this." prefix.
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -1609,7 +1778,7 @@
         static count = 7
       endinterface
   END
-  v9.CheckScriptFailure(lines, 'E1343: Interface name must start with an uppercase letter: somethingWrong')
+  v9.CheckSourceFailure(lines, 'E1343: Interface name must start with an uppercase letter: somethingWrong')
 
   lines =<< trim END
       vim9script
@@ -1619,7 +1788,7 @@
         def GetCount(): number
       endinterface
   END
-  v9.CheckScriptFailure(lines, 'E1344:')
+  v9.CheckSourceFailure(lines, 'E1344:')
 
   lines =<< trim END
       vim9script
@@ -1631,7 +1800,7 @@
         enddef
       endinterface
   END
-  v9.CheckScriptFailure(lines, 'E1345: Not a valid command in an interface: return 5')
+  v9.CheckSourceFailure(lines, 'E1345: Not a valid command in an interface: return 5')
 
   lines =<< trim END
       vim9script
@@ -1699,7 +1868,7 @@
         enddef
       endclass
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -1712,7 +1881,7 @@
         static count: number
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1350:')
+  v9.CheckSourceFailure(lines, 'E1350:')
 
   lines =<< trim END
       vim9script
@@ -1725,7 +1894,7 @@
         static count: number
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1351: Duplicate interface after "implements": Some')
+  v9.CheckSourceFailure(lines, 'E1351: Duplicate interface after "implements": Some')
 
   lines =<< trim END
       vim9script
@@ -1742,7 +1911,7 @@
         enddef
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1348: Member "counter" of interface "Some" not implemented')
+  v9.CheckSourceFailure(lines, 'E1348: Member "counter" of interface "Some" not implemented')
 
   lines =<< trim END
       vim9script
@@ -1759,7 +1928,7 @@
         enddef
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1349: Function "Methods" of interface "Some" not implemented')
+  v9.CheckSourceFailure(lines, 'E1349: Function "Methods" of interface "Some" not implemented')
 
   # Check different order of members in class and interface works.
   lines =<< trim END
@@ -1789,7 +1958,7 @@
 
       Test()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Interface name after "extends" doesn't end in a space or NUL character
   lines =<< trim END
@@ -1799,7 +1968,7 @@
     class B extends A"
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1315:')
+  v9.CheckSourceFailure(lines, 'E1315:')
 
   # Trailing characters after a class name
   lines =<< trim END
@@ -1807,7 +1976,7 @@
     class A bbb
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E488:')
+  v9.CheckSourceFailure(lines, 'E488:')
 
   # using "implements" with a non-existing class
   lines =<< trim END
@@ -1815,7 +1984,7 @@
     class A implements B
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1346:')
+  v9.CheckSourceFailure(lines, 'E1346:')
 
   # using "implements" with a regular class
   lines =<< trim END
@@ -1825,7 +1994,7 @@
     class B implements A
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1347:')
+  v9.CheckSourceFailure(lines, 'E1347:')
 
   # using "implements" with a variable
   lines =<< trim END
@@ -1834,7 +2003,7 @@
     class A implements T
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1347:')
+  v9.CheckSourceFailure(lines, 'E1347:')
 
   # all the class methods in an "interface" should be implemented
   lines =<< trim END
@@ -1845,7 +2014,7 @@
     class B implements A
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1349:')
+  v9.CheckSourceFailure(lines, 'E1349:')
 
   # implements should be followed by a white space
   lines =<< trim END
@@ -1855,7 +2024,7 @@
     class B implements A;
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1315:')
+  v9.CheckSourceFailure(lines, 'E1315:')
 
   lines =<< trim END
       vim9script
@@ -1871,7 +2040,7 @@
         static matching: bool
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1406: Member "not_matching": type mismatch, expected number but got string')
+  v9.CheckSourceFailure(lines, 'E1406: Member "not_matching": type mismatch, expected number but got string')
 
   lines =<< trim END
       vim9script
@@ -1884,7 +2053,7 @@
         enddef
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1407: Method "IsEven": type mismatch, expected func(number): bool but got func(number): string')
+  v9.CheckSourceFailure(lines, 'E1407: Method "IsEven": type mismatch, expected func(number): bool but got func(number): string')
 
   lines =<< trim END
       vim9script
@@ -1897,7 +2066,7 @@
         enddef
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1407: Method "IsEven": type mismatch, expected func(number): bool but got func(bool): bool')
+  v9.CheckSourceFailure(lines, 'E1407: Method "IsEven": type mismatch, expected func(number): bool but got func(bool): bool')
 
   lines =<< trim END
       vim9script
@@ -1910,7 +2079,7 @@
         enddef
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1407: Method "IsEven": type mismatch, expected func(number): bool but got func(number, ...list<number>): bool')
+  v9.CheckSourceFailure(lines, 'E1407: Method "IsEven": type mismatch, expected func(number): bool but got func(number, ...list<number>): bool')
 
   # access superclass interface members from subclass, mix variable order
   lines =<< trim END
@@ -1939,8 +2108,6 @@
 
     class B extends A
         def new()
-            svar1 = 21
-            svar2 = 22
             this.mvar1 = 121
             this.mvar2 = 122
         enddef
@@ -1948,8 +2115,6 @@
 
     class C extends B
         def new()
-            svar1 = 31
-            svar2 = 32
             this.mvar1 = 131
             this.mvar2 = 132
         enddef
@@ -1967,7 +2132,7 @@
     assert_equal([121, 122], F2(ob))
     assert_equal([131, 132], F2(oc))
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Access superclass interface members from subclass, mix variable order.
   # Two interfaces, one on A, one on B; each has both kinds of variables
@@ -2007,8 +2172,6 @@
         public this.mvar3: number
         public this.mvar4: number
         def new()
-            svar1 = 21
-            svar2 = 22
             svar3 = 23
             svar4 = 24
             this.mvar1 = 121
@@ -2021,10 +2184,6 @@
     class C extends B
         public static svar5: number
         def new()
-            svar1 = 31
-            svar2 = 32
-            svar3 = 33
-            svar4 = 34
             svar5 = 1001
             this.mvar1 = 131
             this.mvar2 = 132
@@ -2049,7 +2208,7 @@
     assert_equal([[121, 122], [123, 124]], [F2(ob), F4(ob)])
     assert_equal([[131, 132], [133, 134]], [F2(oc), F4(oc)])
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_call_interface_method()
@@ -2074,7 +2233,7 @@
     assert_equal('child', g:result)
     unlet g:result
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
     vim9script
@@ -2099,7 +2258,7 @@
     assert_equal('child', g:result)
     unlet g:result
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # method of interface returns a value
   lines =<< trim END
@@ -2125,7 +2284,7 @@
     assert_equal('child/resource', g:result)
     unlet g:result
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
     vim9script
@@ -2152,7 +2311,7 @@
     assert_equal('child/resource', g:result)
     unlet g:result
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
 
   # No class that implements the interface.
@@ -2170,7 +2329,7 @@
 
       defcompile
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_class_used_as_type()
@@ -2187,7 +2346,7 @@
       assert_equal(2, p.x)
       assert_equal(33, p.y)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -2206,7 +2365,7 @@
       var hx = p
       assert_equal(2, hx.x)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -2219,7 +2378,7 @@
       var p: Point
       p = 'text'
   END
-  v9.CheckScriptFailure(lines, 'E1012: Type mismatch; expected object<Point> but got string')
+  v9.CheckSourceFailure(lines, 'E1012: Type mismatch; expected object<Point> but got string')
 enddef
 
 def Test_class_extends()
@@ -2243,7 +2402,7 @@
       assert_equal(1, o.GetOne())
       assert_equal(3, o.GetTotal())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -2257,7 +2416,7 @@
       assert_equal(3, o.one)
       assert_equal(44, o.two)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -2268,7 +2427,7 @@
         this.two = 2
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1352: Duplicate "extends"')
+  v9.CheckSourceFailure(lines, 'E1352: Duplicate "extends"')
 
   lines =<< trim END
       vim9script
@@ -2276,7 +2435,7 @@
         this.two = 2
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1353: Class name not found: BaseClass')
+  v9.CheckSourceFailure(lines, 'E1353: Class name not found: BaseClass')
 
   lines =<< trim END
       vim9script
@@ -2285,7 +2444,7 @@
         this.two = 2
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1354: Cannot extend SomeVar')
+  v9.CheckSourceFailure(lines, 'E1354: Cannot extend SomeVar')
 
   lines =<< trim END
       vim9script
@@ -2306,7 +2465,7 @@
       var o = Child.new('John', 42)
       assert_equal('John: 42', o.ToString())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -2320,7 +2479,7 @@
         enddef
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1355: Duplicate function: ToString')
+  v9.CheckSourceFailure(lines, 'E1355: Duplicate function: ToString')
 
   lines =<< trim END
       vim9script
@@ -2333,7 +2492,7 @@
       var o = Child.new(42)
       echo o.ToString()
   END
-  v9.CheckScriptFailure(lines, 'E1356:')
+  v9.CheckSourceFailure(lines, 'E1356:')
 
   lines =<< trim END
       vim9script
@@ -2350,7 +2509,7 @@
       enddef
       echo ToString()
   END
-  v9.CheckScriptFailure(lines, 'E1357:')
+  v9.CheckSourceFailure(lines, 'E1357:')
 
   lines =<< trim END
       vim9script
@@ -2363,7 +2522,7 @@
       var o = Child.new(42)
       echo o.ToString()
   END
-  v9.CheckScriptFailure(lines, 'E1358:')
+  v9.CheckSourceFailure(lines, 'E1358:')
 
   lines =<< trim END
       vim9script
@@ -2384,7 +2543,7 @@
       var o = Child.new('John', 42)
       assert_equal('Base class: 42', o.ToString())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -2401,7 +2560,7 @@
       endclass
       var c = Child.new()
   END
-  v9.CheckScriptFailure(lines, 'E1325: Method not found on class "Child": new(')
+  v9.CheckSourceFailure(lines, 'E1375: Class member "new" accessible only using class "Child"')
 
   # base class with more than one object member
   lines =<< trim END
@@ -2421,7 +2580,7 @@
       var v = Success.new('asdf')
       assert_equal("object of Success {success: true, value: 'asdf'}", string(v))
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # class name after "extends" doesn't end in a space or NUL character
   lines =<< trim END
@@ -2431,7 +2590,7 @@
     class B extends A"
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1315:')
+  v9.CheckSourceFailure(lines, 'E1315:')
 enddef
 
 def Test_using_base_class()
@@ -2470,7 +2629,7 @@
     With(ChildEE.new())
     assert_equal('42/finally/exit', g:result)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
   unlet g:result
 
   # Using super, Child invokes Base method which has optional arg. #12471
@@ -2493,7 +2652,7 @@
     var obj = Child.new()
     assert_equal(true, obj.success)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 
@@ -2536,7 +2695,7 @@
       assert_equal('Peter', p.name)
       assert_equal(42, p.age)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
       vim9script
@@ -2548,14 +2707,14 @@
       endclass
       var p = Base.new('Peter')
   END
-  v9.CheckScriptFailure(lines, 'E1325: Method not found on class "Base": new(')
+  v9.CheckSourceFailure(lines, 'E1325: Method not found on class "Base": new')
 
   lines =<< trim END
       abstract class Base
         this.name: string
       endclass
   END
-  v9.CheckScriptFailure(lines, 'E1316:')
+  v9.CheckSourceFailure(lines, 'E1316:')
 
   # Abstract class cannot have a "new" function
   lines =<< trim END
@@ -2565,7 +2724,7 @@
       enddef
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1359:')
+  v9.CheckSourceFailure(lines, 'E1359:')
 enddef
 
 def Test_closure_in_class()
@@ -2583,7 +2742,7 @@
       Foo.new()
       assert_equal(['A'], g:result)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_call_constructor_from_legacy()
@@ -2606,7 +2765,7 @@
       legacy call p.new()
       assert_equal('true', newCalled)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_defer_with_object()
@@ -2635,7 +2794,7 @@
       })
       assert_equal('entered/called/exited', g:result)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
   unlet g:result
 
   lines =<< trim END
@@ -2672,7 +2831,7 @@
       })
       assert_equal('entered-child/called/exited-child', g:result)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
   unlet g:result
 enddef
 
@@ -2712,7 +2871,7 @@
 
     p.Set(true)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " Test for calling a method in a class that is extended
@@ -2747,7 +2906,7 @@
     assert_true(prop_init_called)
     assert_true(prop_register_called)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_instanceof()
@@ -2794,7 +2953,7 @@
     enddef
     Foo()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " Test for calling a method in the parent class that is extended partially.
@@ -2832,7 +2991,7 @@
     var foo2 = Foo.new()
     var l = Stack(foo1, foo2)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " Test for calling methods from three levels of classes
@@ -2906,7 +3065,7 @@
     assert_equal(0, B_func3)
     assert_equal(3, C_func3)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " Test for using members from three levels of classes
@@ -2949,7 +3108,7 @@
     assert_equal(2, cobj.val2)
     assert_equal(1, cobj.val3)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " Test expansion of <stack> with class methods.
@@ -2973,7 +3132,7 @@
 
     F()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " Test the return type of the new() constructor
@@ -3006,7 +3165,7 @@
     enddef
     F()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # new() uses the default return type and an empty 'return' statement
   lines =<< trim END
@@ -3037,7 +3196,7 @@
     enddef
     F()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # new() uses "any" return type and returns "this"
   lines =<< trim END
@@ -3054,7 +3213,7 @@
       enddef
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1365:')
+  v9.CheckSourceFailure(lines, 'E1365:')
 
   # new() uses 'Dict' return type and returns a Dict
   lines =<< trim END
@@ -3072,7 +3231,7 @@
     var c = C.new()
     assert_equal('object<C>', typename(c))
   END
-  v9.CheckScriptFailure(lines, 'E1365:')
+  v9.CheckSourceFailure(lines, 'E1365:')
 enddef
 
 " Test for checking a member initialization type at run time.
@@ -3098,7 +3257,7 @@
     var c1 = C.new()
     var c2 = C.new()
   END
-  v9.CheckScriptFailure(lines, 'E1012:')
+  v9.CheckSourceFailure(lines, 'E1012:')
 enddef
 
 " Test for locking a variable referring to an object and reassigning to another
@@ -3135,7 +3294,7 @@
     G()
     assert_equal(2, current.val)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " Test for a private object method
@@ -3152,7 +3311,7 @@
     var a = A.new()
     a._Foo()
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo()')
 
   # Try calling a private method using an object (from a def function)
   lines =<< trim END
@@ -3169,7 +3328,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo()')
 
   # Use a private method from another object method (in script context)
   lines =<< trim END
@@ -3186,7 +3345,7 @@
     var a = A.new()
     assert_equal(1234, a.Bar())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Use a private method from another object method (def function context)
   lines =<< trim END
@@ -3206,7 +3365,7 @@
     enddef
     T()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Try calling a private method without the "this" prefix
   lines =<< trim END
@@ -3223,7 +3382,7 @@
     var a = A.new()
     a.Bar()
   END
-  v9.CheckScriptFailure(lines, 'E117: Unknown function: _Foo')
+  v9.CheckSourceFailure(lines, 'E117: Unknown function: _Foo')
 
   # Try calling a private method using the class name
   lines =<< trim END
@@ -3236,7 +3395,7 @@
     endclass
     A._Foo()
   END
-  v9.CheckScriptFailure(lines, 'E1325: Method not found on class "A": _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo')
 
   # Try to use "public" keyword when defining a private method
   lines =<< trim END
@@ -3249,7 +3408,7 @@
     var a = A.new()
     a._Foo()
   END
-  v9.CheckScriptFailure(lines, 'E1331: Public must be followed by "this" or "static"')
+  v9.CheckSourceFailure(lines, 'E1331: Public must be followed by "this" or "static"')
 
   # Define two private methods with the same name
   lines =<< trim END
@@ -3263,7 +3422,7 @@
     endclass
     var a = A.new()
   END
-  v9.CheckScriptFailure(lines, 'E1355: Duplicate function: _Foo')
+  v9.CheckSourceFailure(lines, 'E1355: Duplicate function: _Foo')
 
   # Define a private method and a object method with the same name
   lines =<< trim END
@@ -3277,7 +3436,7 @@
     endclass
     var a = A.new()
   END
-  v9.CheckScriptFailure(lines, 'E1355: Duplicate function: Foo')
+  v9.CheckSourceFailure(lines, 'E1355: Duplicate function: Foo')
 
   # Define an object method and a private method with the same name
   lines =<< trim END
@@ -3291,7 +3450,7 @@
     endclass
     var a = A.new()
   END
-  v9.CheckScriptFailure(lines, 'E1355: Duplicate function: _Foo')
+  v9.CheckSourceFailure(lines, 'E1355: Duplicate function: _Foo')
 
   # Call a public method and a private method from a private method
   lines =<< trim END
@@ -3315,7 +3474,7 @@
     var a = A.new()
     a.T()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Try calling a private method from another class
   lines =<< trim END
@@ -3335,7 +3494,7 @@
     var b = B.new()
     b.Foo()
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo()')
 
   # Call a private object method from a child class object method
   lines =<< trim END
@@ -3357,7 +3516,7 @@
     var c = C.new()
     assert_equal(1234, c.Baz())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Call a private object method from a child class object
   lines =<< trim END
@@ -3378,7 +3537,7 @@
     var c = C.new()
     assert_equal(1234, c._Foo())
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo()')
 
   # Using "_" prefix in a method name should fail outside of a class
   lines =<< trim END
@@ -3388,7 +3547,7 @@
     enddef
     var a = _Foo()
   END
-  v9.CheckScriptFailure(lines, 'E1267: Function name must start with a capital: _Foo(): number')
+  v9.CheckSourceFailure(lines, 'E1267: Function name must start with a capital: _Foo(): number')
 enddef
 
 " Test for an private class method
@@ -3404,7 +3563,7 @@
     endclass
     A._Foo()
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo()')
 
   # Try calling a class private method (from a def function)
   lines =<< trim END
@@ -3420,7 +3579,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo()')
 
   # Try calling a class private method using an object (at the script level)
   lines =<< trim END
@@ -3434,7 +3593,7 @@
     var a = A.new()
     a._Foo()
   END
-  v9.CheckScriptFailure(lines, 'E1325: Method not found on class "A": _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo')
 
   # Try calling a class private method using an object (from a def function)
   lines =<< trim END
@@ -3451,7 +3610,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1325: Method not found on class "A": _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo')
 
   # Use a class private method from an object method
   lines =<< trim END
@@ -3468,7 +3627,7 @@
     var a = A.new()
     a.Bar()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Use a class private method from another class private method
   lines =<< trim END
@@ -3488,7 +3647,7 @@
     var a = A.new()
     a.Bar()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Declare a class method and a class private method with the same name
   lines =<< trim END
@@ -3502,7 +3661,7 @@
     endclass
     var a = A.new()
   END
-  v9.CheckScriptFailure(lines, 'E1355: Duplicate function: Foo')
+  v9.CheckSourceFailure(lines, 'E1355: Duplicate function: Foo')
 
   # Try calling a class private method from another class
   lines =<< trim END
@@ -3521,7 +3680,7 @@
     var b = B.new()
     assert_equal(1234, b.Foo())
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo()')
 
   # Call a private class method from a child class object method
   lines =<< trim END
@@ -3543,7 +3702,7 @@
     var c = C.new()
     assert_equal(1234, c.Baz())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo()')
 
   # Call a private class method from a child class private class method
   lines =<< trim END
@@ -3564,7 +3723,7 @@
     endclass
     assert_equal(1234, C.Baz())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo()')
 
   # Call a private class method from a child class object
   lines =<< trim END
@@ -3585,7 +3744,7 @@
     var c = C.new()
     assert_equal(1234, C._Foo())
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo()')
+  v9.CheckSourceFailure(lines, 'E1325: Method not found on class "C": _Foo')
 enddef
 
 " Test for an interface private object_method
@@ -3607,7 +3766,7 @@
     var a = A.new()
     assert_equal(1234, a.Bar())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Call an interface private class method (script context)
   lines =<< trim END
@@ -3623,7 +3782,7 @@
     var a = A.new()
     assert_equal(1234, a._Foo())
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo()')
 
   # Call an interface private class method (def context)
   lines =<< trim END
@@ -3642,7 +3801,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo()')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo()')
 
   # Implement an interface private object method as a private class method
   lines =<< trim END
@@ -3656,7 +3815,7 @@
       enddef
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1349: Function "_Foo" of interface "Intf" not implemented')
+  v9.CheckSourceFailure(lines, 'E1349: Function "_Foo" of interface "Intf" not implemented')
 enddef
 
 " Test for an interface private class method
@@ -3678,7 +3837,7 @@
     var a = A.new()
     assert_equal(1234, a.Bar())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Call an interface private class method (script context)
   lines =<< trim END
@@ -3693,7 +3852,7 @@
     endclass
     assert_equal(1234, A._Foo())
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo())')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo())')
 
   # Call an interface private class method (def context)
   lines =<< trim END
@@ -3711,7 +3870,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1366: Cannot access private method: _Foo())')
+  v9.CheckSourceFailure(lines, 'E1366: Cannot access private method: _Foo())')
 
   # Implement an interface private class method as a private object method
   lines =<< trim END
@@ -3725,7 +3884,7 @@
       enddef
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1349: Function "_Foo" of interface "Intf" not implemented')
+  v9.CheckSourceFailure(lines, 'E1349: Function "_Foo" of interface "Intf" not implemented')
 enddef
 
 " Test for using the return value of a class/object method as a function
@@ -3751,7 +3910,7 @@
     var t = C.new()
     Baz(t)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   lines =<< trim END
     vim9script
@@ -3772,7 +3931,7 @@
 
     Baz()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_static_inheritence()
@@ -3797,21 +3956,17 @@
 
     class B extends A
         def new()
-            _svar = 2
             this._mvar = 102
         enddef
     endclass
 
     class C extends B
         def new()
-            _svar = 3
             this._mvar = 103
         enddef
 
         def AccessPrivateStaticThroughClassName(): number
             assert_equal(1, A._svar)
-            assert_equal(2, B._svar)
-            assert_equal(3, C._svar)
             return 444
         enddef
     endclass
@@ -3823,14 +3978,14 @@
     assert_equal(102, ob.AccessObject())
     assert_equal(103, oc.AccessObject())
 
-    assert_equal(444, oc.AccessPrivateStaticThroughClassName())
+    assert_fails('echo oc.AccessPrivateStaticThroughClassName()', 'E1333: Cannot access private member: _svar')
 
     # verify object properly resolves to correct static
     assert_equal(1, oa.AccessStaticThroughObject())
-    assert_equal(2, ob.AccessStaticThroughObject())
-    assert_equal(3, oc.AccessStaticThroughObject())
+    assert_equal(1, ob.AccessStaticThroughObject())
+    assert_equal(1, oc.AccessStaticThroughObject())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " Test for declaring duplicate object and class members
@@ -3843,7 +3998,7 @@
       this.val = 20
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: val')
+  v9.CheckSourceFailure(lines, 'E1369: Duplicate member: val')
 
   # Duplicate private member variable
   lines =<< trim END
@@ -3853,7 +4008,7 @@
       this._val = 20
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: _val')
+  v9.CheckSourceFailure(lines, 'E1369: Duplicate member: _val')
 
   # Duplicate public member variable
   lines =<< trim END
@@ -3863,7 +4018,7 @@
       public this.val = 20
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: val')
+  v9.CheckSourceFailure(lines, 'E1369: Duplicate member: val')
 
   # Duplicate private member variable
   lines =<< trim END
@@ -3873,7 +4028,7 @@
       this._val = 20
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: _val')
+  v9.CheckSourceFailure(lines, 'E1369: Duplicate member: _val')
 
   # Duplicate public and private member variable
   lines =<< trim END
@@ -3883,7 +4038,7 @@
       public this.val = 10
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: val')
+  v9.CheckSourceFailure(lines, 'E1369: Duplicate member: val')
 
   # Duplicate class member variable
   lines =<< trim END
@@ -3893,7 +4048,7 @@
       static _s: string = "def"
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: _s')
+  v9.CheckSourceFailure(lines, 'E1369: Duplicate member: _s')
 
   # Duplicate public and private class member variable
   lines =<< trim END
@@ -3903,7 +4058,7 @@
       static _s: string = "def"
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: _s')
+  v9.CheckSourceFailure(lines, 'E1369: Duplicate member: _s')
 
   # Duplicate class and object member variable
   lines =<< trim END
@@ -3918,7 +4073,7 @@
     assert_equal(10, C.val)
     assert_equal(20, c.val)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Duplicate object member variable in a derived class
   lines =<< trim END
@@ -3932,7 +4087,7 @@
       this.val = 20
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: val')
+  v9.CheckSourceFailure(lines, 'E1369: Duplicate member: val')
 
   # Duplicate object private member variable in a derived class
   lines =<< trim END
@@ -3946,7 +4101,7 @@
       this._val = 20
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: _val')
+  v9.CheckSourceFailure(lines, 'E1369: Duplicate member: _val')
 
   # Duplicate object private member variable in a derived class
   lines =<< trim END
@@ -3960,7 +4115,7 @@
       this._val = 20
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: _val')
+  v9.CheckSourceFailure(lines, 'E1369: Duplicate member: _val')
 
   # Duplicate object member variable in a derived class
   lines =<< trim END
@@ -3974,63 +4129,7 @@
       this.val = 20
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: val')
-
-  # Duplicate class member variable in a derived class
-  lines =<< trim END
-    vim9script
-    class A
-      static val = 10
-    endclass
-    class B extends A
-    endclass
-    class C extends B
-      static val = 20
-    endclass
-  END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: val')
-
-  # Duplicate private class member variable in a derived class
-  lines =<< trim END
-    vim9script
-    class A
-      static _val = 10
-    endclass
-    class B extends A
-    endclass
-    class C extends B
-      static _val = 20
-    endclass
-  END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: _val')
-
-  # Duplicate private class member variable in a derived class
-  lines =<< trim END
-    vim9script
-    class A
-      static val = 10
-    endclass
-    class B extends A
-    endclass
-    class C extends B
-      static _val = 20
-    endclass
-  END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: _val')
-
-  # Duplicate class member variable in a derived class
-  lines =<< trim END
-    vim9script
-    class A
-      static _val = 10
-    endclass
-    class B extends A
-    endclass
-    class C extends B
-      static val = 20
-    endclass
-  END
-  v9.CheckScriptFailure(lines, 'E1369: Duplicate member: val')
+  v9.CheckSourceFailure(lines, 'E1369: Duplicate member: val')
 
   # Two member variables with a common prefix
   lines =<< trim END
@@ -4040,7 +4139,7 @@
       public static svar: number
     endclass
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 def Test_interface_static_member_access()
@@ -4058,7 +4157,7 @@
     endclass
     C.new().F()
   END
-  v9.CheckScriptFailure(lines, 'E1409: Cannot directly access interface "I" static member "num"')
+  v9.CheckSourceFailure(lines, 'E1409: Cannot directly access interface "I" static member "num"')
 
   # In a class cannot write to interface static
   lines =<< trim END
@@ -4074,7 +4173,7 @@
     endclass
     C.new().F()
   END
-  v9.CheckScriptFailure(lines, 'E1409: Cannot directly access interface "I" static member "num"')
+  v9.CheckSourceFailure(lines, 'E1409: Cannot directly access interface "I" static member "num"')
 
   # In a def cannot read from interface static
   lines =<< trim END
@@ -4087,7 +4186,7 @@
     enddef
     F()
   END
-  v9.CheckScriptFailure(lines, 'E1409: Cannot directly access interface "I" static member "num"')
+  v9.CheckSourceFailure(lines, 'E1409: Cannot directly access interface "I" static member "num"')
 
   # In a def cannot write to interface static
   lines =<< trim END
@@ -4100,7 +4199,7 @@
     enddef
     F()
   END
-  v9.CheckScriptFailure(lines, 'E1409: Cannot directly access interface "I" static member "num"')
+  v9.CheckSourceFailure(lines, 'E1409: Cannot directly access interface "I" static member "num"')
 
   # script level cannot read interface static
   lines =<< trim END
@@ -4111,7 +4210,7 @@
 
     var x = I.s_var1
   END
-  v9.CheckScriptFailure(lines, 'E1409: Cannot directly access interface "I" static member "s_var1"')
+  v9.CheckSourceFailure(lines, 'E1409: Cannot directly access interface "I" static member "s_var1"')
 
   # script level cannot write interface static
   lines =<< trim END
@@ -4122,7 +4221,7 @@
 
     I.s_var1 = 3
   END
-  v9.CheckScriptFailure(lines, 'E1409: Cannot directly access interface "I" static member "I.s_var1 = 3"')
+  v9.CheckSourceFailure(lines, 'E1409: Cannot directly access interface "I" static member "I.s_var1 = 3"')
 
 enddef
 
@@ -4158,7 +4257,7 @@
 
     assert_equal(11, F1())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " Test for accessing a private member outside a class in a def function
@@ -4178,7 +4277,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1333: Cannot access private member: _val')
+  v9.CheckSourceFailure(lines, 'E1333: Cannot access private member: _val')
 
   # access a non-existing private object member variable
   lines =<< trim END
@@ -4192,7 +4291,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1089: Unknown variable: _a = 1')
+  v9.CheckSourceFailure(lines, 'E1089: Unknown variable: _a')
 
   # private static member variable
   lines =<< trim END
@@ -4206,7 +4305,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1326: Member not found on object "A": _val')
+  v9.CheckSourceFailure(lines, 'E1375: Class member "_val" accessible only using class "A"')
 
   # private static member variable
   lines =<< trim END
@@ -4220,8 +4319,7 @@
     enddef
     T()
   END
-  # TODO: wrong error, should be about private member
-  v9.CheckScriptFailure(lines, 'E1089: Unknown variable')
+  v9.CheckSourceFailure(lines, 'E1374: Class member "_val" accessible only inside class "A"')
 
   # private static class variable
   lines =<< trim END
@@ -4234,7 +4332,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1333: Cannot access private member: _val')
+  v9.CheckSourceFailure(lines, 'E1333: Cannot access private member: _val')
 
   # private static class variable
   lines =<< trim END
@@ -4247,7 +4345,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1333: Cannot access private member: _val')
+  v9.CheckSourceFailure(lines, 'E1333: Cannot access private member: _val')
 enddef
 
 " Test for changing the member access of an interface in a implementation class
@@ -4261,7 +4359,7 @@
       this.val = 10
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1367: Access level of member "val" of interface "A" is different')
+  v9.CheckSourceFailure(lines, 'E1367: Access level of member "val" of interface "A" is different')
 
   lines =<< trim END
     vim9script
@@ -4272,7 +4370,7 @@
       public this.val = 10
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1367: Access level of member "val" of interface "A" is different')
+  v9.CheckSourceFailure(lines, 'E1367: Access level of member "val" of interface "A" is different')
 enddef
 
 " Test for trying to change a readonly member from a def function
@@ -4288,7 +4386,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E46: Cannot change read-only variable "val"')
+  v9.CheckSourceFailure(lines, 'E46: Cannot change read-only variable "val"')
 enddef
 
 " Test for reading and writing a class member from a def function
@@ -4312,7 +4410,7 @@
     enddef
     T()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " Test for accessing a class member variable using an object
@@ -4337,7 +4435,7 @@
     enddef
     Foo()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Cannot read from a class variable using an object in script context
   lines =<< trim END
@@ -4350,7 +4448,7 @@
     var a = A.new()
     echo a.svar2
   END
-  v9.CheckScriptFailure(lines, 'E1326: Member not found on object "A": svar2')
+  v9.CheckSourceFailure(lines, 'E1375: Class member "svar2" accessible only using class "A"')
 
   # Cannot write to a class variable using an object in script context
   lines =<< trim END
@@ -4363,7 +4461,7 @@
     var a = A.new()
     a.svar2 = [2]
   END
-  v9.CheckScriptFailure(lines, 'E1334: Object member not found: svar2 = [2]')
+  v9.CheckSourceFailure(lines, 'E1375: Class member "svar2" accessible only using class "A"')
 
   # Cannot read from a class variable using an object in def method context
   lines =<< trim END
@@ -4379,7 +4477,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1326: Member not found on object "A": svar2')
+  v9.CheckSourceFailure(lines, 'E1375: Class member "svar2" accessible only using class "A"')
 
   # Cannot write to a class variable using an object in def method context
   lines =<< trim END
@@ -4395,7 +4493,7 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1089: Unknown variable: svar2 = [2]')
+  v9.CheckSourceFailure(lines, 'E1374: Class member "svar2" accessible only inside class "A"')
 enddef
 
 " Test for using a interface method using a child object
@@ -4431,7 +4529,7 @@
     T1(c)
     T2(c)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " Test for using an interface method using a child object when it is overridden
@@ -4472,7 +4570,7 @@
 "     T1(c)
 "     T2(c)
 "   END
-"   v9.CheckScriptSuccess(lines)
+"   v9.CheckSourceSuccess(lines)
 " enddef
 
 " Test for abstract methods
@@ -4498,7 +4596,7 @@
     var b = B.new()
     assert_equal([10, 20, 30], [b.M1(), b.M2(), b.M3()])
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Don't define an abstract method
   lines =<< trim END
@@ -4509,7 +4607,7 @@
     class B extends A
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1373: Abstract method "Foo" is not implemented')
+  v9.CheckSourceFailure(lines, 'E1373: Abstract method "Foo" is not implemented')
 
   # Use abstract method in a concrete class
   lines =<< trim END
@@ -4520,7 +4618,7 @@
     class B extends A
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1372: Abstract method "abstract def Foo()" cannot be defined in a concrete class')
+  v9.CheckSourceFailure(lines, 'E1372: Abstract method "abstract def Foo()" cannot be defined in a concrete class')
 
   # Use abstract method in an interface
   lines =<< trim END
@@ -4531,7 +4629,7 @@
     class B implements A
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1372: Abstract method "abstract def Foo()" cannot be defined in a concrete class')
+  v9.CheckSourceFailure(lines, 'E1372: Abstract method "abstract def Foo()" cannot be defined in a concrete class')
 
   # Abbreviate the "abstract" keyword
   lines =<< trim END
@@ -4540,7 +4638,7 @@
       abs def Foo()
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1065: Command cannot be shortened: abs def Foo()')
+  v9.CheckSourceFailure(lines, 'E1065: Command cannot be shortened: abs def Foo()')
 
   # Use "abstract" with a member variable
   lines =<< trim END
@@ -4549,7 +4647,7 @@
       abstract this.val = 10
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1371: Abstract must be followed by "def" or "static"')
+  v9.CheckSourceFailure(lines, 'E1371: Abstract must be followed by "def" or "static"')
 
   # Use a static abstract method
   lines =<< trim END
@@ -4564,7 +4662,7 @@
     endclass
     assert_equal(4, B.Foo())
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Type mismatch between abstract method and concrete method
   lines =<< trim END
@@ -4578,7 +4676,7 @@
       enddef
     endclass
   END
-  v9.CheckScriptFailure(lines, 'E1407: Method "Foo": type mismatch, expected func(string, number): list<number> but got func(number, string): list<string>')
+  v9.CheckSourceFailure(lines, 'E1407: Method "Foo": type mismatch, expected func(string, number): list<number> but got func(number, string): list<string>')
 
   # Use an abstract class to invoke an abstract method
   # FIXME: This should fail
@@ -4589,7 +4687,7 @@
     endclass
     A.Foo()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # Invoke an abstract method from a def function
   lines =<< trim END
@@ -4608,7 +4706,31 @@
     var b = B.new()
     Bar(b)
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
+enddef
+
+" Test for calling a class method from a subclass
+def Test_class_method_call_from_subclass()
+  # class method call from a subclass
+  var lines =<< trim END
+    vim9script
+
+    class A
+      static def Foo()
+        echo "foo"
+      enddef
+    endclass
+
+    class B extends A
+      def Bar()
+        Foo()
+      enddef
+    endclass
+
+    var b = B.new()
+    b.Bar()
+  END
+  v9.CheckSourceFailure(lines, 'E1374: Class member "Foo" accessible only inside class "A"')
 enddef
 
 " Test for calling a class method using an object in a def function context and
@@ -4638,7 +4760,7 @@
     a.Bar()
     T()
   END
-  v9.CheckScriptSuccess(lines)
+  v9.CheckSourceSuccess(lines)
 
   # script context
   lines =<< trim END
@@ -4652,7 +4774,7 @@
     var a = A.new()
     assert_equal('foo', a.Foo())
   END
-  v9.CheckScriptFailure(lines, 'E1325: Method not found on class "A": Foo()')
+  v9.CheckSourceFailure(lines, 'E1375: Class member "Foo" accessible only using class "A"')
 
   # def function context
   lines =<< trim END
@@ -4669,7 +4791,407 @@
     enddef
     T()
   END
-  v9.CheckScriptFailure(lines, 'E1325: Method not found on class "A": Foo()')
+  v9.CheckSourceFailure(lines, 'E1375: Class member "Foo" accessible only using class "A"')
+enddef
+
+def Test_class_variable()
+  var lines =<< trim END
+    vim9script
+
+    class A
+      public static val: number = 10
+      static def ClassFunc()
+        assert_equal(10, val)
+      enddef
+      def ObjFunc()
+        assert_equal(10, val)
+      enddef
+    endclass
+
+    class B extends A
+    endclass
+
+    assert_equal(10, A.val)
+    A.ClassFunc()
+    var a = A.new()
+    a.ObjFunc()
+    var b = B.new()
+    b.ObjFunc()
+
+    def T1(a1: A)
+      a1.ObjFunc()
+      A.ClassFunc()
+    enddef
+    T1(b)
+
+    A.val = 20
+    assert_equal(20, A.val)
+  END
+  v9.CheckSourceSuccess(lines)
+
+  # Modifying a parent class variable from a child class method
+  lines =<< trim END
+    vim9script
+
+    class A
+      static val: number = 10
+    endclass
+
+    class B extends A
+      static def ClassFunc()
+        val = 20
+      enddef
+    endclass
+    B.ClassFunc()
+  END
+  v9.CheckSourceFailure(lines, 'E1374: Class member "val" accessible only inside class "A"')
+
+  # Reading a parent class variable from a child class method
+  lines =<< trim END
+    vim9script
+
+    class A
+      static val: number = 10
+    endclass
+
+    class B extends A
+      static def ClassFunc()
+        var i = val
+      enddef
+    endclass
+    B.ClassFunc()
+  END
+  v9.CheckSourceFailure(lines, 'E1374: Class member "val" accessible only inside class "A"')
+
+  # Modifying a parent class variable from a child object method
+  lines =<< trim END
+    vim9script
+
+    class A
+      static val: number = 10
+    endclass
+
+    class B extends A
+      def ObjFunc()
+        val = 20
+      enddef
+    endclass
+    var b = B.new()
+    b.ObjFunc()
+  END
+  v9.CheckSourceFailure(lines, 'E1374: Class member "val" accessible only inside class "A"')
+
+  # Reading a parent class variable from a child object method
+  lines =<< trim END
+    vim9script
+
+    class A
+      static val: number = 10
+    endclass
+
+    class B extends A
+      def ObjFunc()
+        var i = val
+      enddef
+    endclass
+    var b = B.new()
+    b.ObjFunc()
+  END
+  v9.CheckSourceFailure(lines, 'E1374: Class member "val" accessible only inside class "A"')
+
+  # Modifying a class variable using an object at script level
+  lines =<< trim END
+    vim9script
+
+    class A
+      static val: number = 10
+    endclass
+    var a = A.new()
+    a.val = 20
+  END
+  v9.CheckSourceFailure(lines, 'E1375: Class member "val" accessible only using class "A"')
+
+  # Reading a class variable using an object at script level
+  lines =<< trim END
+    vim9script
+
+    class A
+      static val: number = 10
+    endclass
+    var a = A.new()
+    var i = a.val
+  END
+  v9.CheckSourceFailure(lines, 'E1375: Class member "val" accessible only using class "A"')
+
+  # Modifying a class variable using an object at function level
+  lines =<< trim END
+    vim9script
+
+    class A
+      static val: number = 10
+    endclass
+
+    def T()
+      var a = A.new()
+      a.val = 20
+    enddef
+    T()
+  END
+  v9.CheckSourceFailure(lines, 'E1374: Class member "val" accessible only inside class "A"')
+
+  # Reading a class variable using an object at function level
+  lines =<< trim END
+    vim9script
+
+    class A
+      static val: number = 10
+    endclass
+    def T()
+      var a = A.new()
+      var i = a.val
+    enddef
+    T()
+  END
+  v9.CheckSourceFailure(lines, 'E1375: Class member "val" accessible only using class "A"')
+enddef
+
+" Test for using a duplicate class method and class variable in a child class
+def Test_dup_class_member()
+  # duplicate class variable, class method and overridden object method
+  var lines =<< trim END
+    vim9script
+    class A
+      static sval = 100
+      static def Check()
+        assert_equal(100, sval)
+      enddef
+      def GetVal(): number
+        return sval
+      enddef
+    endclass
+
+    class B extends A
+      static sval = 200
+      static def Check()
+        assert_equal(200, sval)
+      enddef
+      def GetVal(): number
+        return sval
+      enddef
+    endclass
+
+    def T1(aa: A): number
+      return aa.GetVal()
+    enddef
+
+    def T2(bb: B): number
+      return bb.GetVal()
+    enddef
+
+    assert_equal(100, A.sval)
+    assert_equal(200, B.sval)
+    var a = A.new()
+    assert_equal(100, a.GetVal())
+    var b = B.new()
+    assert_equal(200, b.GetVal())
+    assert_equal(200, T1(b))
+    assert_equal(200, T2(b))
+  END
+  v9.CheckSourceSuccess(lines)
+
+  # duplicate class variable and class method
+  lines =<< trim END
+    vim9script
+    class A
+      static sval = 100
+      static def Check()
+        assert_equal(100, sval)
+      enddef
+      def GetVal(): number
+        return sval
+      enddef
+    endclass
+
+    class B extends A
+      static sval = 200
+      static def Check()
+        assert_equal(200, sval)
+      enddef
+    endclass
+
+    def T1(aa: A): number
+      return aa.GetVal()
+    enddef
+
+    def T2(bb: B): number
+      return bb.GetVal()
+    enddef
+
+    assert_equal(100, A.sval)
+    assert_equal(200, B.sval)
+    var a = A.new()
+    assert_equal(100, a.GetVal())
+    var b = B.new()
+    assert_equal(100, b.GetVal())
+    assert_equal(100, T1(b))
+    assert_equal(100, T2(b))
+  END
+  v9.CheckSourceSuccess(lines)
+enddef
+
+" Test for calling an instance method using the class
+def Test_instance_method_call_using_class()
+  # Invoke an object method using a class in script context
+  var lines =<< trim END
+    vim9script
+    class A
+      def Foo()
+        echo "foo"
+      enddef
+    endclass
+    A.Foo()
+  END
+  v9.CheckSourceFailure(lines, 'E1376: Object member "Foo" accessible only using class "A" object')
+
+  # Invoke an object method using a class in def function context
+  lines =<< trim END
+    vim9script
+    class A
+      def Foo()
+        echo "foo"
+      enddef
+    endclass
+    def T()
+      A.Foo()
+    enddef
+    T()
+  END
+  v9.CheckSourceFailure(lines, 'E1376: Object member "Foo" accessible only using class "A" object')
+enddef
+
+" Test for duplicate class method and instance method
+def Test_dup_classmethod_objmethod()
+  # Duplicate instance method
+  var lines =<< trim END
+    vim9script
+    class A
+      static def Foo()
+      enddef
+      def Foo()
+      enddef
+    endclass
+  END
+  v9.CheckSourceFailure(lines, 'E1355: Duplicate function: Foo')
+
+  # Duplicate private instance method
+  lines =<< trim END
+    vim9script
+    class A
+      static def Foo()
+      enddef
+      def _Foo()
+      enddef
+    endclass
+  END
+  v9.CheckSourceFailure(lines, 'E1355: Duplicate function: _Foo')
+
+  # Duplicate class method
+  lines =<< trim END
+    vim9script
+    class A
+      def Foo()
+      enddef
+      static def Foo()
+      enddef
+    endclass
+  END
+  v9.CheckSourceFailure(lines, 'E1355: Duplicate function: Foo')
+
+  # Duplicate private class method
+  lines =<< trim END
+    vim9script
+    class A
+      def Foo()
+      enddef
+      static def _Foo()
+      enddef
+    endclass
+  END
+  v9.CheckSourceFailure(lines, 'E1355: Duplicate function: _Foo')
+
+  # Duplicate private class and object method
+  lines =<< trim END
+    vim9script
+    class A
+      def _Foo()
+      enddef
+      static def _Foo()
+      enddef
+    endclass
+  END
+  v9.CheckSourceFailure(lines, 'E1355: Duplicate function: _Foo')
+enddef
+
+" Test for an instance method access level comparison with parent instance
+" methods.
+def Test_instance_method_access_level()
+  # Private method in subclass
+  var lines =<< trim END
+    vim9script
+    class A
+      def Foo()
+      enddef
+    endclass
+    class B extends A
+    endclass
+    class C extends B
+      def _Foo()
+      enddef
+    endclass
+  END
+  v9.CheckSourceFailure(lines, 'E1378: Access level of method "_Foo" is different in class "A"')
+
+  # Public method in subclass
+  lines =<< trim END
+    vim9script
+    class A
+      def _Foo()
+      enddef
+    endclass
+    class B extends A
+    endclass
+    class C extends B
+      def Foo()
+      enddef
+    endclass
+  END
+  v9.CheckSourceFailure(lines, 'E1378: Access level of method "Foo" is different in class "A"')
+enddef
+
+def Test_extend_empty_class()
+  var lines =<< trim END
+    vim9script
+    class A
+    endclass
+    class B extends A
+    endclass
+    class C extends B
+      public static rw_class_var = 1
+      public this.rw_obj_var = 2
+      static def ClassMethod(): number
+        return 3
+      enddef
+      def ObjMethod(): number
+        return 4
+      enddef
+    endclass
+    assert_equal(1, C.rw_class_var)
+    assert_equal(3, C.ClassMethod())
+    var c = C.new()
+    assert_equal(2, c.rw_obj_var)
+    assert_equal(4, c.ObjMethod())
+  END
+  v9.CheckSourceSuccess(lines)
 enddef
 
 " vim: ts=8 sw=2 sts=2 expandtab tw=80 fdm=marker
diff --git a/src/testdir/vim9.vim b/src/testdir/vim9.vim
index 5877a79..782809b 100644
--- a/src/testdir/vim9.vim
+++ b/src/testdir/vim9.vim
@@ -110,6 +110,40 @@
   endtry
 enddef
 
+# :source a list of "lines" and check whether it fails with "error"
+export def CheckSourceFailure(lines: list<string>, error: string, lnum = -3)
+  new
+  setline(1, lines)
+  try
+    assert_fails('source', error, lines, lnum)
+  finally
+    bw!
+  endtry
+enddef
+
+# :source a list of "lines" and check whether it fails with the list of
+# "errors"
+export def CheckSourceFailureList(lines: list<string>, errors: list<string>, lnum = -3)
+  new
+  setline(1, lines)
+  try
+    assert_fails('source', errors, lines, lnum)
+  finally
+    bw!
+  endtry
+enddef
+
+# :source a list of "lines" and check whether it succeeds
+export def CheckSourceSuccess(lines: list<string>)
+  new
+  setline(1, lines)
+  try
+    :source
+  finally
+    bw!
+  endtry
+enddef
+
 export def CheckDefAndScriptSuccess(lines: list<string>)
   CheckDefSuccess(lines)
   CheckScriptSuccess(['vim9script'] + lines)