From c7360f9af3cfafcfb1b5f3cc0f3ad2fbdef27b90 Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@medvednikov.com>
Date: Thu, 26 Feb 2026 10:18:43 +0300
Subject: [PATCH] checker: fix embedded struct member visibility (fixes #13607)

---
 vlib/v/checker/fn.v                            |  3 ++-
 .../embedded_private_method_visibility.out     |  1 +
 .../drawlib.v                                  | 12 ++++++++++++
 .../embedded_private_method_visibility/main.v  | 18 ++++++++++++++++++
 4 files changed, 33 insertions(+), 1 deletion(-)
 create mode 100644 vlib/v/checker/tests/modules/embedded_private_method_visibility.out
 create mode 100644 vlib/v/checker/tests/modules/embedded_private_method_visibility/drawlib.v
 create mode 100644 vlib/v/checker/tests/modules/embedded_private_method_visibility/main.v

diff --git a/vlib/v/checker/fn.v b/vlib/v/checker/fn.v
index ac91b07e2..45a738c4a 100644
--- a/vlib/v/checker/fn.v
+++ b/vlib/v/checker/fn.v
@@ -2518,7 +2518,8 @@ fn (mut c Checker) method_call(mut node ast.CallExpr, mut continue_check &bool)
 	if method.return_type.has_flag(.generic) {
 		node.return_type_generic = method.return_type
 	}
-	if !method.is_pub && method.mod != c.mod {
+	is_used_outside_receiver_module := left_sym.mod != c.mod && method.mod != c.mod
+	if !method.is_pub && is_used_outside_receiver_module {
 		// If a private method is called outside of the module
 		// its receiver type is defined in, show an error.
 		// println('warn ${method_name} lef.mod=${left_type_sym.mod} c.mod=${c.mod}')
diff --git a/vlib/v/checker/tests/modules/embedded_private_method_visibility.out b/vlib/v/checker/tests/modules/embedded_private_method_visibility.out
new file mode 100644
index 000000000..d00491fd7
--- /dev/null
+++ b/vlib/v/checker/tests/modules/embedded_private_method_visibility.out
@@ -0,0 +1 @@
+1
diff --git a/vlib/v/checker/tests/modules/embedded_private_method_visibility/drawlib.v b/vlib/v/checker/tests/modules/embedded_private_method_visibility/drawlib.v
new file mode 100644
index 000000000..4a882db62
--- /dev/null
+++ b/vlib/v/checker/tests/modules/embedded_private_method_visibility/drawlib.v
@@ -0,0 +1,12 @@
+module drawlib
+
+pub struct TextDrawer {
+mut:
+	runes []rune
+}
+
+fn (mut td TextDrawer) calc_wordwrap() {
+	if td.runes.len == 0 {
+		td.runes << `Z`
+	}
+}
diff --git a/vlib/v/checker/tests/modules/embedded_private_method_visibility/main.v b/vlib/v/checker/tests/modules/embedded_private_method_visibility/main.v
new file mode 100644
index 000000000..865aa08ee
--- /dev/null
+++ b/vlib/v/checker/tests/modules/embedded_private_method_visibility/main.v
@@ -0,0 +1,18 @@
+module main
+
+import drawlib
+
+struct TextBox {
+	drawlib.TextDrawer
+}
+
+fn (mut tb TextBox) set() {
+	tb.runes << `A`
+	tb.calc_wordwrap()
+}
+
+fn main() {
+	mut tb := TextBox{}
+	tb.set()
+	println(tb.runes.len)
+}
-- 
2.39.5