From ee7bcfd05cc1743ef1f5b37f91473a35257583fa Mon Sep 17 00:00:00 2001
From: Henrixounez <30901439+Henrixounez@users.noreply.github.com>
Date: Sun, 18 Apr 2021 15:26:40 +0200
Subject: [PATCH] =?UTF-8?q?checker:=20prevent=20double=20module=20name=20p?=
 =?UTF-8?q?repending=20on=20generics=20types=20regi=E2=80=A6=20(#9791)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 vlib/v/checker/checker.v                 |  2 +-
 vlib/v/tests/generics_in_generics_test.v | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)
 create mode 100644 vlib/v/tests/generics_in_generics_test.v

diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index c8a90c36e3..ab61db3a1c 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -1929,7 +1929,7 @@ pub fn (mut c Checker) fn_call(mut call_expr ast.CallExpr) ast.Type {
 		}
 	}
 	if has_generic_generic {
-		if c.mod != '' {
+		if c.mod != '' && !fn_name.starts_with('${c.mod}.') {
 			// Need to prepend the module when adding a generic type to a function
 			c.table.register_fn_generic_types(c.mod + '.' + fn_name, generic_types)
 		} else {
diff --git a/vlib/v/tests/generics_in_generics_test.v b/vlib/v/tests/generics_in_generics_test.v
new file mode 100644
index 0000000000..3e2149d548
--- /dev/null
+++ b/vlib/v/tests/generics_in_generics_test.v
@@ -0,0 +1,12 @@
+fn gen_fn2<T>(e T) string {
+	return '$e.str()'
+}
+
+fn gen_fn<T>(e T) string {
+	return gen_fn2<T>(e)
+}
+
+fn test_generics_in_generics() {
+	assert gen_fn(u64(42)) == '42'
+	assert gen_fn('42') == '42'
+}