From f4586b1577bee988ad8f135a5ae282f53c105fff Mon Sep 17 00:00:00 2001
From: yuyi <yuyi98@163.com>
Date: Sat, 30 Apr 2022 10:29:33 +0800
Subject: [PATCH] parser: make sure interface field names use uppercase letters
 (#14228)

---
 .../tests/interface_field_name_err.out        | 20 +++++++++++++++++++
 .../checker/tests/interface_field_name_err.vv |  8 ++++++++
 vlib/v/parser/struct.v                        |  3 ++-
 3 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 vlib/v/checker/tests/interface_field_name_err.out
 create mode 100644 vlib/v/checker/tests/interface_field_name_err.vv

diff --git a/vlib/v/checker/tests/interface_field_name_err.out b/vlib/v/checker/tests/interface_field_name_err.out
new file mode 100644
index 0000000000..0b1e3bcdfc
--- /dev/null
+++ b/vlib/v/checker/tests/interface_field_name_err.out
@@ -0,0 +1,20 @@
+vlib/v/checker/tests/interface_field_name_err.vv:2:2: error: field name `Age` cannot contain uppercase letters, use snake_case instead
+    1 | interface Animal {
+    2 |     Age int
+      |     ~~~
+    3 |     Foo &int
+    4 |     Bar []string
+vlib/v/checker/tests/interface_field_name_err.vv:3:2: error: field name `Foo` cannot contain uppercase letters, use snake_case instead
+    1 | interface Animal {
+    2 |     Age int
+    3 |     Foo &int
+      |     ~~~
+    4 |     Bar []string
+    5 | }
+vlib/v/checker/tests/interface_field_name_err.vv:4:2: error: field name `Bar` cannot contain uppercase letters, use snake_case instead
+    2 |     Age int
+    3 |     Foo &int
+    4 |     Bar []string
+      |     ~~~
+    5 | }
+    6 |
diff --git a/vlib/v/checker/tests/interface_field_name_err.vv b/vlib/v/checker/tests/interface_field_name_err.vv
new file mode 100644
index 0000000000..7d9d748c7c
--- /dev/null
+++ b/vlib/v/checker/tests/interface_field_name_err.vv
@@ -0,0 +1,8 @@
+interface Animal {
+	Age int
+	Foo &int
+	Bar []string
+}
+
+fn main() {
+}
diff --git a/vlib/v/parser/struct.v b/vlib/v/parser/struct.v
index 016afd3f2f..24985e747e 100644
--- a/vlib/v/parser/struct.v
+++ b/vlib/v/parser/struct.v
@@ -517,7 +517,8 @@ fn (mut p Parser) interface_decl() ast.InterfaceDecl {
 	mut ifaces := []ast.InterfaceEmbedding{}
 	for p.tok.kind != .rcbr && p.tok.kind != .eof {
 		if p.tok.kind == .name && p.tok.lit.len > 0 && p.tok.lit[0].is_capital()
-			&& p.peek_tok.kind != .lpar {
+			&& (p.peek_tok.line_nr != p.tok.line_nr
+			|| p.peek_tok.kind !in [.name, .amp, .lsbr, .lpar]) {
 			iface_pos := p.tok.pos()
 			mut iface_name := p.tok.lit
 			iface_type := p.parse_type()