From e67ce5ea7bddf0a54d4945fc0e4ef74e9271b9dc Mon Sep 17 00:00:00 2001
From: yuyi <yuyi98@163.com>
Date: Tue, 9 Mar 2021 19:25:31 +0800
Subject: [PATCH] cgen: fix error of alias interpolation (#9209)

---
 vlib/v/gen/c/str.v                             | 6 +++++-
 vlib/v/tests/string_interpolation_alias_test.v | 8 ++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/vlib/v/gen/c/str.v b/vlib/v/gen/c/str.v
index 37f27cbe98..3e531089e2 100644
--- a/vlib/v/gen/c/str.v
+++ b/vlib/v/gen/c/str.v
@@ -204,7 +204,11 @@ fn (mut g Gen) string_inter_literal(node ast.StringInterLiteral) {
 			break
 		}
 		g.write(escaped_val)
-		typ := g.unwrap_generic(node.expr_types[i])
+		mut typ := g.unwrap_generic(node.expr_types[i])
+		sym := g.table.get_type_symbol(typ)
+		if sym.kind == .alias {
+			typ = (sym.info as table.Alias).parent_type
+		}
 		// write correct format specifier to intermediate string
 		g.write('%')
 		fspec := node.fmts[i]
diff --git a/vlib/v/tests/string_interpolation_alias_test.v b/vlib/v/tests/string_interpolation_alias_test.v
index 6d620eb180..cb576e07db 100644
--- a/vlib/v/tests/string_interpolation_alias_test.v
+++ b/vlib/v/tests/string_interpolation_alias_test.v
@@ -15,3 +15,11 @@ fn test_map_alias_string() {
 	assert '$m'.contains("'one': '1'")
 	assert '$m'.contains("'two': '2'")
 }
+
+type Duration = i64
+
+fn test_i64_number_alias_string() {
+    x := i64(9_123_456_789)
+    y := Duration(x)
+    assert '$x' == '$y'
+}