patch 9.1.2012: Vim9: cannot initialize class member with protected var

Problem:  Vim9: cannot initialize class member with protected var
Solution: Allow this to work if this happens within the same class
          (Foxe Chen)

closes: #18949

Signed-off-by: Foxe Chen <chen.foxe@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/eval.c

@@ -131,6 +131,7 @@ fill_evalarg_from_eap(evalarg_T *evalarg, exarg_T *eap, int skip)
 	evalarg->eval_getline = eap->ea_getline;
 	evalarg->eval_cookie = eap->cookie;
     }
+    evalarg->eval_class = eap->class;
 }
 
 /*

src/ex_cmds.h

@@ -1973,6 +1973,8 @@ struct exarg
     void	*cookie;	// argument for getline()
 #ifdef FEAT_EVAL
     cstack_T	*cstack;	// condition stack for ":if" etc.
+    class_T	*class;		// Name of class being defined. Used by :class
+				// and :enum commands.
 #endif
 };
 

src/globals.h

@@ -2025,7 +2025,7 @@ EXTERN listitem_T range_list_item;
 EXTERN evalarg_T EVALARG_EVALUATE
 # ifdef DO_INIT
 	= {EVAL_EVALUATE, 0, NULL, NULL, NULL, NULL, GA_EMPTY, GA_EMPTY, NULL,
-			 {0, 0, (int)sizeof(char_u *), 20, NULL}, 0, NULL}
+			 {0, 0, (int)sizeof(char_u *), 20, NULL}, 0, NULL, NULL}
 # endif
 	;
 #endif

src/structs.h

@@ -2282,6 +2282,9 @@ typedef struct {
 
     // pointer to the lines concatenated for a lambda.
     char_u	*eval_tofree_lambda;
+
+    // pointer to name of class being constructed
+    class_T	*eval_class;
 } evalarg_T;
 
 // Flag for expression evaluation.

src/testdir/test_vim9_class.vim

@@ -12407,10 +12407,14 @@ def Test_protected_new_method()
     vim9script
     class A
       static var _instance: A
+      static var handler: func = A._Internal
       var str: string
       def _new(str: string)
         this.str = str
       enddef
+      static def _Internal(): string
+        return "test"
+      enddef
       static def GetInstance(str: string): A
         if _instance == null
           _instance = A._new(str)
@@ -12422,6 +12426,24 @@ def Test_protected_new_method()
     var b: A = A.GetInstance('bar')
     assert_equal('foo', a.str)
     assert_equal('foo', b.str)
+    assert_equal('test', A.handler())
+  END
+  v9.CheckSourceSuccess(lines)
+
+  lines =<< trim END
+    vim9script
+    enum Test
+      A,
+      B,
+      C
+
+      static var handler: func = Test._Internal
+
+      static def _Internal(): string
+        return "test"
+      enddef
+    endenum
+    assert_equal('test', Test.handler())
   END
   v9.CheckSourceSuccess(lines)
 enddef

src/version.c

@@ -734,6 +734,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2012,
 /**/
     2011,
 /**/

src/vim9class.c

@@ -2122,6 +2122,8 @@ early_ret:
     cl->class_object_type.tt_type = VAR_OBJECT;
     cl->class_object_type.tt_class = cl;
 
+    eap->class = cl;
+
     // Add the class to the script-local variables.
     // TODO: handle other context, e.g. in a function
     // TODO: does uf_hash need to be cleared?
@@ -3243,7 +3245,8 @@ class_object_index(
 	if (fp != NULL)
 	{
 	    // Protected methods are not accessible outside the class
-	    if (*name == '_')
+	    if (fp->uf_defclass != evalarg->eval_class
+		    && *name == '_')
 	    {
 		semsg(_(e_cannot_access_protected_method_str), fp->uf_name);
 		goto done;