checker: show position for variadic/shared/method argument errors (#8939)

vlib/v/checker/checker.v

@@ -1526,8 +1526,8 @@ pub fn (mut c Checker) call_method(mut call_expr ast.CallExpr) table.Type {
 			got_arg_typ := c.expr(arg.expr)
 			call_expr.args[i].typ = got_arg_typ
 			if method.is_variadic && got_arg_typ.has_flag(.variadic) && call_expr.args.len - 1 > i {
-				c.error('when forwarding a varg variable, it must be the final argument',
-					call_expr.pos)
+				c.error('when forwarding a variadic variable, it must be the final argument',
+					arg.pos)
 			}
 			if exp_arg_sym.kind == .interface_ {
 				c.type_implements(got_arg_typ, exp_arg_typ, arg.expr.position())
@@ -1545,7 +1545,7 @@ pub fn (mut c Checker) call_method(mut call_expr ast.CallExpr) table.Type {
 				// }
 				if got_arg_typ != table.void_type {
 					c.error('$err in argument ${i + 1} to `${left_type_sym.name}.$method_name`',
-						call_expr.pos)
+						arg.pos)
 				}
 			}
 			param := if method.is_variadic && i >= method.params.len - 1 {
@@ -1556,7 +1556,7 @@ pub fn (mut c Checker) call_method(mut call_expr ast.CallExpr) table.Type {
 			param_share := param.typ.share()
 			if param_share == .shared_t && (c.locked_names.len > 0 || c.rlocked_names.len > 0) {
 				c.error('method with `shared` arguments cannot be called inside `lock`/`rlock` block',
-					call_expr.pos)
+					arg.pos)
 			}
 			if arg.is_mut {
 				to_lock, pos := c.fail_if_immutable(arg.expr)
@@ -1932,13 +1932,13 @@ pub fn (mut c Checker) call_fn(mut call_expr ast.CallExpr) table.Type {
 		typ_sym := c.table.get_type_symbol(typ)
 		arg_typ_sym := c.table.get_type_symbol(arg.typ)
 		if f.is_variadic && typ.has_flag(.variadic) && call_expr.args.len - 1 > i {
-			c.error('when forwarding a varg variable, it must be the final argument',
-				call_expr.pos)
+			c.error('when forwarding a variadic variable, it must be the final argument',
+				call_arg.pos)
 		}
 		arg_share := arg.typ.share()
 		if arg_share == .shared_t && (c.locked_names.len > 0 || c.rlocked_names.len > 0) {
 			c.error('function with `shared` arguments cannot be called inside `lock`/`rlock` block',
-				call_expr.pos)
+				call_arg.pos)
 		}
 		if call_arg.is_mut {
 			to_lock, pos := c.fail_if_immutable(call_arg.expr)

vlib/v/checker/tests/fn_variadic.out

@@ -0,0 +1,14 @@
+vlib/v/checker/tests/fn_variadic.vv:3:8: error: when forwarding a variadic variable, it must be the final argument
+    1 | fn f(vi ...int) int {
+    2 |     _ = f(...vi) // OK
+    3 |     _ = f(...vi, 2)
+      |           ~~~~~
+    4 |     return 0
+    5 | }
+vlib/v/checker/tests/fn_variadic.vv:11:10: error: when forwarding a variadic variable, it must be the final argument
+    9 | fn (s S1) m(vi ...int) int {
+   10 |     _ = s.m(...vi) // OK
+   11 |     _ = s.m(...vi, 2)
+      |             ~~~~~
+   12 |     return 0
+   13 | }

vlib/v/checker/tests/fn_variadic.vv

@@ -0,0 +1,13 @@
+fn f(vi ...int) int {
+	_ = f(...vi) // OK
+	_ = f(...vi, 2)
+	return 0
+}
+
+struct S1 {}
+
+fn (s S1) m(vi ...int) int {
+	_ = s.m(...vi) // OK
+	_ = s.m(...vi, 2)
+	return 0
+}

vlib/v/checker/tests/function_variadic_arg_non_final.out

@@ -1,5 +0,0 @@
-vlib/v/checker/tests/function_variadic_arg_non_final.vv:1:6: error: cannot use ...(variadic) with non-final parameter para1
-    1 | fn f(para1 ...int, para2 f32) int {
-      |      ~~~~~
-    2 |     return 22
-    3 | }

vlib/v/checker/tests/method_wrong_arg_type.out

@@ -1,13 +1,13 @@
-vlib/v/checker/tests/method_wrong_arg_type.vv:10:4: error: cannot use `MyEnum` as `string` in argument 1 to `Sss.info`
+vlib/v/checker/tests/method_wrong_arg_type.vv:10:9: error: cannot use `MyEnum` as `string` in argument 1 to `Sss.info`
     8 |     e := MyEnum.x
     9 |     s := Sss{}
    10 |     s.info(e)
-      |       ~~~~~~~
+      |            ^
    11 | }
    12 |
-vlib/v/checker/tests/method_wrong_arg_type.vv:18:4: error: cannot use `int` as `&Sss` in argument 1 to `Sss.ptr`
+vlib/v/checker/tests/method_wrong_arg_type.vv:18:8: error: cannot use `int` as `&Sss` in argument 1 to `Sss.ptr`
    16 |     s := Sss{}
    17 |     v := 4
    18 |     s.ptr(v)
-      |       ~~~~~~
+      |           ^
    19 | }

vlib/v/checker/tests/shared_lock.out

@@ -0,0 +1,21 @@
+vlib/v/checker/tests/shared_lock.vv:19:5: error: method with `shared` receiver cannot be called inside `lock`/`rlock` block
+   17 |     }
+   18 |     lock x {
+   19 |         x.r(x)
+      |           ~~~~
+   20 |         x.m(x)
+   21 |         f(0, x)
+vlib/v/checker/tests/shared_lock.vv:20:7: error: method with `shared` arguments cannot be called inside `lock`/`rlock` block
+   18 |     lock x {
+   19 |         x.r(x)
+   20 |         x.m(x)
+      |             ^
+   21 |         f(0, x)
+   22 |     }
+vlib/v/checker/tests/shared_lock.vv:21:8: error: function with `shared` arguments cannot be called inside `lock`/`rlock` block
+   19 |         x.r(x)
+   20 |         x.m(x)
+   21 |         f(0, x)
+      |              ^
+   22 |     }
+   23 | }

vlib/v/checker/tests/shared_lock.vv

@@ -0,0 +1,23 @@
+struct St {
+mut:
+	a int
+}
+fn (shared s St) r(x St) {
+}
+fn (s St) m(shared x St) {
+}
+
+
+fn f(w int, shared x St) {
+}
+
+fn g() {
+	shared x := St{
+		a: 5
+	}
+	lock x {
+		x.r(x)
+		x.m(x)
+		f(0, x)
+	}
+}

vlib/v/parser/tests/function_variadic_arg_non_final.out

@@ -0,0 +1,5 @@
+vlib/v/parser/tests/function_variadic_arg_non_final.vv:1:6: error: cannot use ...(variadic) with non-final parameter para1
+    1 | fn f(para1 ...int, para2 f32) int {
+      |      ~~~~~
+    2 |     return 22
+    3 | }