patch 8.2.2306: Vim9: when using function reference type is not checked

Problem:    Vim9: when using function reference type is not checked.
Solution:   When using a function reference lookup the type and check the
            argument types. (issue #7629)

src/eval.c

@@ -721,8 +721,10 @@ call_func_retlist(
 
 #ifdef FEAT_FOLDING
 /*
- * Evaluate 'foldexpr'.  Returns the foldlevel, and any character preceding
+ * Evaluate "arg", which is 'foldexpr'.
- * it in "*cp".  Doesn't give error messages.
+ * Note: caller must set "curwin" to match "arg".
+ * Returns the foldlevel, and any character preceding it in "*cp".  Doesn't
+ * give error messages.
  */
     int
 eval_foldexpr(char_u *arg, int *cp)
@@ -809,6 +811,7 @@ get_lval(
     int		len;
     hashtab_T	*ht = NULL;
     int		quiet = flags & GLV_QUIET;
+    int		writing;
 
     // Clear everything in "lp".
     CLEAR_POINTER(lp);
@@ -882,10 +885,10 @@ get_lval(
 
     cc = *p;
     *p = NUL;
-    // Only pass &ht when we would write to the variable, it prevents autoload
+    // When we would write to the variable pass &ht and prevent autoload.
-    // as well.
+    writing = !(flags & GLV_READ_ONLY);
-    v = find_var(lp->ll_name, (flags & GLV_READ_ONLY) ? NULL : &ht,
+    v = find_var(lp->ll_name, writing ? &ht : NULL,
-						      flags & GLV_NO_AUTOLOAD);
+					 (flags & GLV_NO_AUTOLOAD) || writing);
     if (v == NULL && !quiet)
 	semsg(_(e_undefined_variable_str), lp->ll_name);
     *p = cc;
@@ -1972,13 +1975,15 @@ eval_func(
     int		len = name_len;
     partial_T	*partial;
     int		ret = OK;
+    type_T	*type = NULL;
 
     if (!evaluate)
 	check_vars(s, len);
 
     // If "s" is the name of a variable of type VAR_FUNC
     // use its contents.
-    s = deref_func_name(s, &len, &partial, !evaluate);
+    s = deref_func_name(s, &len, &partial,
+				    in_vim9script() ? &type : NULL, !evaluate);
 
     // Need to make a copy, in case evaluating the arguments makes
     // the name invalid.
@@ -1996,6 +2001,7 @@ eval_func(
 	funcexe.evaluate = evaluate;
 	funcexe.partial = partial;
 	funcexe.basetv = basetv;
+	funcexe.check_type = type;
 	ret = get_func_tv(s, len, rettv, arg, evalarg, &funcexe);
     }
     vim_free(s);

src/evalfunc.c

@@ -3497,7 +3497,8 @@ common_function(typval_T *argvars, typval_T *rettv, int is_funcref)
     {
 	name = s;
 	trans_name = trans_function_name(&name, &is_global, FALSE,
-	     TFN_INT | TFN_QUIET | TFN_NO_AUTOLOAD | TFN_NO_DEREF, NULL, NULL);
+	     TFN_INT | TFN_QUIET | TFN_NO_AUTOLOAD | TFN_NO_DEREF,
+							     NULL, NULL, NULL);
 	if (*name != NUL)
 	    s = NULL;
     }

src/evalvars.c

@@ -2639,8 +2639,7 @@ check_vars(char_u *name, int len)
  * Find variable "name" in the list of variables.
  * Return a pointer to it if found, NULL if not found.
  * Careful: "a:0" variables don't have a name.
- * When "htp" is not NULL we are writing to the variable, set "htp" to the
+ * When "htp" is not NULL  set "htp" to the hashtab_T used.
- * hashtab_T used.
  */
     dictitem_T *
 find_var(char_u *name, hashtab_T **htp, int no_autoload)
@@ -2654,12 +2653,12 @@ find_var(char_u *name, hashtab_T **htp, int no_autoload)
 	*htp = ht;
     if (ht == NULL)
 	return NULL;
-    ret = find_var_in_ht(ht, *name, varname, no_autoload || htp != NULL);
+    ret = find_var_in_ht(ht, *name, varname, no_autoload);
     if (ret != NULL)
 	return ret;
 
     // Search in parent scope for lambda
-    ret = find_var_in_scoped_ht(name, no_autoload || htp != NULL);
+    ret = find_var_in_scoped_ht(name, no_autoload);
     if (ret != NULL)
 	return ret;
 
@@ -2669,8 +2668,7 @@ find_var(char_u *name, hashtab_T **htp, int no_autoload)
 	ht = get_script_local_ht();
 	if (ht != NULL)
 	{
-	    ret = find_var_in_ht(ht, *name, varname,
+	    ret = find_var_in_ht(ht, *name, varname, no_autoload);
-						   no_autoload || htp != NULL);
 	    if (ret != NULL)
 	    {
 		if (htp != NULL)

src/proto/userfunc.pro

@@ -4,7 +4,7 @@ hashtab_T *func_tbl_get(void);
 char_u *get_lambda_name(void);
 char_u *register_cfunc(cfunc_T cb, cfunc_free_T cb_free, void *state);
 int get_lambda_tv(char_u **arg, typval_T *rettv, int types_optional, evalarg_T *evalarg);
-char_u *deref_func_name(char_u *name, int *lenp, partial_T **partialp, int no_autoload);
+char_u *deref_func_name(char_u *name, int *lenp, partial_T **partialp, type_T **type, int no_autoload);
 void emsg_funcname(char *ermsg, char_u *name);
 int get_func_tv(char_u *name, int len, typval_T *rettv, char_u **arg, evalarg_T *evalarg, funcexe_T *funcexe);
 char_u *fname_trans_sid(char_u *name, char_u *fname_buf, char_u **tofree, int *error);
@@ -31,7 +31,7 @@ int call_callback(callback_T *callback, int len, typval_T *rettv, int argcount,
 void user_func_error(int error, char_u *name);
 int call_func(char_u *funcname, int len, typval_T *rettv, int argcount_in, typval_T *argvars_in, funcexe_T *funcexe);
 char_u *printable_func_name(ufunc_T *fp);
-char_u *trans_function_name(char_u **pp, int *is_global, int skip, int flags, funcdict_T *fdp, partial_T **partial);
+char_u *trans_function_name(char_u **pp, int *is_global, int skip, int flags, funcdict_T *fdp, partial_T **partial, type_T **type);
 char_u *untrans_function_name(char_u *name);
 void list_functions(regmatch_T *regmatch);
 ufunc_T *define_function(exarg_T *eap, char_u *name_arg);

src/proto/vim9type.pro

@@ -16,6 +16,7 @@ void type_mismatch(type_T *expected, type_T *actual);
 void arg_type_mismatch(type_T *expected, type_T *actual, int argidx);
 int check_type(type_T *expected, type_T *actual, int give_msg, int argidx);
 int check_arg_type(type_T *expected, type_T *actual, int argidx);
+int check_argument_types(type_T *type, typval_T *argvars, int argcount, char_u *name);
 char_u *skip_type(char_u *start, int optional);
 type_T *parse_type(char_u **arg, garray_T *type_gap, int give_error);
 int equal_type(type_T *type1, type_T *type2);

src/structs.h

@@ -1944,6 +1944,7 @@ typedef struct {
     partial_T	*partial;	// for extra arguments
     dict_T	*selfdict;	// Dictionary for "self"
     typval_T	*basetv;	// base for base->method()
+    type_T	*check_type;	// type from funcref or NULL
 } funcexe_T;
 
 /*

src/testdir/test_vim9_func.vim

@@ -579,6 +579,22 @@ def Test_call_funcref_wrong_args()
 
   CheckScriptFailure(head + ["funcMap['func']('str', 123)"] + tail, 'E119:')
   CheckScriptFailure(head + ["funcMap['func']('str', 123, [1], 4)"] + tail, 'E118:')
+
+  var lines =<< trim END
+      vim9script
+      var Ref: func(number): any
+      Ref = (j) => !j
+      echo Ref(false)
+  END
+  CheckScriptFailure(lines, 'E1013: Argument 1: type mismatch, expected number but got bool', 4)
+
+  lines =<< trim END
+      vim9script
+      var Ref: func(number): any
+      Ref = (j) => !j
+      call Ref(false)
+  END
+  CheckScriptFailure(lines, 'E1013: Argument 1: type mismatch, expected number but got bool', 4)
 enddef
 
 def Test_call_lambda_args()

src/userfunc.c

@@ -727,47 +727,68 @@ errret:
  * name it contains, otherwise return "name".
  * If "partialp" is not NULL, and "name" is of type VAR_PARTIAL also set
  * "partialp".
+ * If "type" is not NULL and a Vim9 script-local variable is found look up the
+ * type of the variable.
  */
     char_u *
-deref_func_name(char_u *name, int *lenp, partial_T **partialp, int no_autoload)
+deref_func_name(
+	char_u	    *name,
+	int	    *lenp,
+	partial_T   **partialp,
+	type_T	    **type,
+	int	    no_autoload)
 {
     dictitem_T	*v;
     int		cc;
-    char_u	*s;
+    char_u	*s = NULL;
+    hashtab_T	*ht;
 
     if (partialp != NULL)
 	*partialp = NULL;
 
     cc = name[*lenp];
     name[*lenp] = NUL;
-    v = find_var(name, NULL, no_autoload);
+    v = find_var(name, &ht, no_autoload);
     name[*lenp] = cc;
-    if (v != NULL && v->di_tv.v_type == VAR_FUNC)
+    if (v != NULL)
     {
-	if (v->di_tv.vval.v_string == NULL)
+	if (v->di_tv.v_type == VAR_FUNC)
 	{
-	    *lenp = 0;
+	    if (v->di_tv.vval.v_string == NULL)
-	    return (char_u *)"";	// just in case
+	    {
+		*lenp = 0;
+		return (char_u *)"";	// just in case
+	    }
+	    s = v->di_tv.vval.v_string;
+	    *lenp = (int)STRLEN(s);
 	}
-	s = v->di_tv.vval.v_string;
-	*lenp = (int)STRLEN(s);
-	return s;
-    }
 
-    if (v != NULL && v->di_tv.v_type == VAR_PARTIAL)
+	if (v->di_tv.v_type == VAR_PARTIAL)
-    {
-	partial_T *pt = v->di_tv.vval.v_partial;
-
-	if (pt == NULL)
 	{
-	    *lenp = 0;
+	    partial_T *pt = v->di_tv.vval.v_partial;
-	    return (char_u *)"";	// just in case
+
+	    if (pt == NULL)
+	    {
+		*lenp = 0;
+		return (char_u *)"";	// just in case
+	    }
+	    if (partialp != NULL)
+		*partialp = pt;
+	    s = partial_name(pt);
+	    *lenp = (int)STRLEN(s);
+	}
+
+	if (s != NULL)
+	{
+	    if (type != NULL && ht == get_script_local_ht())
+	    {
+		svar_T  *sv = find_typval_in_script(&v->di_tv);
+
+		if (sv != NULL)
+		    *type = sv->sv_type;
+	    }
+	    return s;
 	}
-	if (partialp != NULL)
-	    *partialp = pt;
-	s = partial_name(pt);
-	*lenp = (int)STRLEN(s);
-	return s;
     }
 
     return name;
@@ -2387,6 +2408,14 @@ call_func(
 	}
     }
 
+    if (error == FCERR_NONE && funcexe->check_type != NULL && funcexe->evaluate)
+    {
+	// Check that the argument types are OK for the types of the funcref.
+	if (check_argument_types(funcexe->check_type, argvars, argcount,
+								 name) == FAIL)
+	    error = FCERR_OTHER;
+    }
+
     if (error == FCERR_NONE && funcexe->evaluate)
     {
 	char_u *rfname = fname;
@@ -2629,7 +2658,8 @@ trans_function_name(
     int		skip,		// only find the end, don't evaluate
     int		flags,
     funcdict_T	*fdp,		// return: info about dictionary used
-    partial_T	**partial)	// return: partial of a FuncRef
+    partial_T	**partial,	// return: partial of a FuncRef
+    type_T	**type)		// return: type of funcref if not NULL
 {
     char_u	*name = NULL;
     char_u	*start;
@@ -2733,7 +2763,7 @@ trans_function_name(
     if (lv.ll_exp_name != NULL)
     {
 	len = (int)STRLEN(lv.ll_exp_name);
-	name = deref_func_name(lv.ll_exp_name, &len, partial,
+	name = deref_func_name(lv.ll_exp_name, &len, partial, type,
 						     flags & TFN_NO_AUTOLOAD);
 	if (name == lv.ll_exp_name)
 	    name = NULL;
@@ -2741,7 +2771,8 @@ trans_function_name(
     else if (!(flags & TFN_NO_DEREF))
     {
 	len = (int)(end - *pp);
-	name = deref_func_name(*pp, &len, partial, flags & TFN_NO_AUTOLOAD);
+	name = deref_func_name(*pp, &len, partial, type,
+						      flags & TFN_NO_AUTOLOAD);
 	if (name == *pp)
 	    name = NULL;
     }
@@ -3064,7 +3095,7 @@ define_function(exarg_T *eap, char_u *name_arg)
     else
     {
 	name = trans_function_name(&p, &is_global, eap->skip,
-						 TFN_NO_AUTOLOAD, &fudi, NULL);
+					   TFN_NO_AUTOLOAD, &fudi, NULL, NULL);
 	paren = (vim_strchr(p, '(') != NULL);
 	if (name == NULL && (fudi.fd_dict == NULL || !paren) && !eap->skip)
 	{
@@ -3479,7 +3510,8 @@ define_function(exarg_T *eap, char_u *name_arg)
 		if (*p == '!')
 		    p = skipwhite(p + 1);
 		p += eval_fname_script(p);
-		vim_free(trans_function_name(&p, NULL, TRUE, 0, NULL, NULL));
+		vim_free(trans_function_name(&p, NULL, TRUE, 0, NULL,
+								  NULL, NULL));
 		if (*skipwhite(p) == '(')
 		{
 		    if (nesting == MAX_FUNC_NESTING - 1)
@@ -3616,7 +3648,7 @@ define_function(exarg_T *eap, char_u *name_arg)
     {
 	hashtab_T	*ht;
 
-	v = find_var(name, &ht, FALSE);
+	v = find_var(name, &ht, TRUE);
 	if (v != NULL && v->di_tv.v_type == VAR_FUNC)
 	{
 	    emsg_funcname(N_("E707: Function name conflicts with variable: %s"),
@@ -4007,7 +4039,7 @@ function_exists(char_u *name, int no_deref)
     flag = TFN_INT | TFN_QUIET | TFN_NO_AUTOLOAD;
     if (no_deref)
 	flag |= TFN_NO_DEREF;
-    p = trans_function_name(&nm, &is_global, FALSE, flag, NULL, NULL);
+    p = trans_function_name(&nm, &is_global, FALSE, flag, NULL, NULL, NULL);
     nm = skipwhite(nm);
 
     // Only accept "funcname", "funcname ", "funcname (..." and
@@ -4027,7 +4059,7 @@ get_expanded_name(char_u *name, int check)
     int		is_global = FALSE;
 
     p = trans_function_name(&nm, &is_global, FALSE,
-						TFN_INT|TFN_QUIET, NULL, NULL);
+					  TFN_INT|TFN_QUIET, NULL, NULL, NULL);
 
     if (p != NULL && *nm == NUL
 		       && (!check || translated_function_exists(p, is_global)))
@@ -4097,7 +4129,8 @@ ex_delfunction(exarg_T *eap)
     int		is_global = FALSE;
 
     p = eap->arg;
-    name = trans_function_name(&p, &is_global, eap->skip, 0, &fudi, NULL);
+    name = trans_function_name(&p, &is_global, eap->skip, 0, &fudi,
+								   NULL, NULL);
     vim_free(fudi.fd_newkey);
     if (name == NULL)
     {
@@ -4328,6 +4361,7 @@ ex_call(exarg_T *eap)
     funcdict_T	fudi;
     partial_T	*partial = NULL;
     evalarg_T	evalarg;
+    type_T	*type = NULL;
 
     fill_evalarg_from_eap(&evalarg, eap, eap->skip);
     if (eap->skip)
@@ -4343,8 +4377,8 @@ ex_call(exarg_T *eap)
 	return;
     }
 
-    tofree = trans_function_name(&arg, NULL, eap->skip,
+    tofree = trans_function_name(&arg, NULL, eap->skip, TFN_INT,
-						     TFN_INT, &fudi, &partial);
+			      &fudi, &partial, in_vim9script() ? &type : NULL);
     if (fudi.fd_newkey != NULL)
     {
 	// Still need to give an error message for missing key.
@@ -4363,8 +4397,8 @@ ex_call(exarg_T *eap)
     // contents.  For VAR_PARTIAL get its partial, unless we already have one
     // from trans_function_name().
     len = (int)STRLEN(tofree);
-    name = deref_func_name(tofree, &len,
+    name = deref_func_name(tofree, &len, partial != NULL ? NULL : &partial,
-				    partial != NULL ? NULL : &partial, FALSE);
+			in_vim9script() && type == NULL ? &type : NULL, FALSE);
 
     // Skip white space to allow ":call func ()".  Not good, but required for
     // backward compatibility.
@@ -4416,6 +4450,7 @@ ex_call(exarg_T *eap)
 	funcexe.evaluate = !eap->skip;
 	funcexe.partial = partial;
 	funcexe.selfdict = fudi.fd_dict;
+	funcexe.check_type = type;
 	if (get_func_tv(name, -1, &rettv, &arg, &evalarg, &funcexe) == FAIL)
 	{
 	    failed = TRUE;

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2306,
 /**/
     2305,
 /**/

src/vim9compile.c

@@ -1790,9 +1790,9 @@ generate_PCALL(
 						       stack->ga_len + offset];
 		    type_T *expected;
 
-		    if (varargs && i >= type->tt_min_argcount - 1)
+		    if (varargs && i >= type->tt_argcount - 1)
 			expected = type->tt_args[
-					 type->tt_min_argcount - 1]->tt_member;
+					     type->tt_argcount - 1]->tt_member;
 		    else
 			expected = type->tt_args[i];
 		    if (need_type(actual, expected, offset,

src/vim9execute.c

@@ -3423,7 +3423,7 @@ ex_disassemble(exarg_T *eap)
     }
     else
 	fname = trans_function_name(&arg, &is_global, FALSE,
-			    TFN_INT | TFN_QUIET | TFN_NO_AUTOLOAD, NULL, NULL);
+		      TFN_INT | TFN_QUIET | TFN_NO_AUTOLOAD, NULL, NULL, NULL);
     if (fname == NULL)
     {
 	semsg(_(e_invarg2), eap->arg);

src/vim9type.c

@@ -527,6 +527,46 @@ check_arg_type(type_T *expected, type_T *actual, int argidx)
     return check_type(expected, actual, TRUE, argidx);
 }
 
+/*
+ * Check that the arguments of "type" match "argvars[argcount]".
+ * Return OK/FAIL.
+ */
+    int
+check_argument_types(type_T *type, typval_T *argvars, int argcount, char_u *name)
+{
+    int	    varargs = (type->tt_flags & TTFLAG_VARARGS) ? 1 : 0;
+    int	    i;
+
+    if (type->tt_type != VAR_FUNC && type->tt_type != VAR_PARTIAL)
+	return OK;  // just in case
+    if (argcount < type->tt_min_argcount - varargs)
+    {
+	semsg(_(e_toofewarg), name);
+	return FAIL;
+    }
+    if (!varargs && type->tt_argcount >= 0 && argcount > type->tt_argcount)
+    {
+	semsg(_(e_toomanyarg), name);
+	return FAIL;
+    }
+    if (type->tt_args == NULL)
+	return OK;  // cannot check
+
+
+    for (i = 0; i < argcount; ++i)
+    {
+	type_T	*expected;
+
+	if (varargs && i >= type->tt_argcount - 1)
+	    expected = type->tt_args[type->tt_argcount - 1]->tt_member;
+	else
+	    expected = type->tt_args[i];
+	if (check_typval_type(expected, &argvars[i], i + 1) == FAIL)
+	    return FAIL;
+    }
+    return OK;
+}
+
 /*
  * Skip over a type definition and return a pointer to just after it.
  * When "optional" is TRUE then a leading "?" is accepted.