From daeb548e7b284cf4423362b4a640355845d5e532 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Sat, 19 Oct 2024 21:51:02 -0300
Subject: [PATCH] cgen: fix codegen for if with struct init that contains
 option type (fix #22577) (#22578)

---
 vlib/v/ast/types.v                            |  1 +
 vlib/v/gen/c/if.v                             |  2 ++
 vlib/v/parser/struct.v                        |  3 ++
 .../options/option_struct_init_on_if_test.v   | 36 +++++++++++++++++++
 4 files changed, 42 insertions(+)
 create mode 100644 vlib/v/tests/options/option_struct_init_on_if_test.v

diff --git a/vlib/v/ast/types.v b/vlib/v/ast/types.v
index 271a6fa89..52f951780 100644
--- a/vlib/v/ast/types.v
+++ b/vlib/v/ast/types.v
@@ -169,6 +169,7 @@ pub mut:
 	is_minify      bool
 	is_anon        bool
 	is_generic     bool
+	has_option     bool // contains any option field
 	generic_types  []Type
 	concrete_types []Type
 	parent_type    Type
diff --git a/vlib/v/gen/c/if.v b/vlib/v/gen/c/if.v
index e89cde29e..048eb57ee 100644
--- a/vlib/v/gen/c/if.v
+++ b/vlib/v/gen/c/if.v
@@ -156,6 +156,8 @@ fn (mut g Gen) need_tmp_var_in_expr(expr ast.Expr) bool {
 					return true
 				}
 			}
+			sym := g.table.sym(expr.typ)
+			return sym.info is ast.Struct && sym.info.has_option
 		}
 		else {}
 	}
diff --git a/vlib/v/parser/struct.v b/vlib/v/parser/struct.v
index d2d564904..b8ed12afb 100644
--- a/vlib/v/parser/struct.v
+++ b/vlib/v/parser/struct.v
@@ -97,6 +97,7 @@ fn (mut p Parser) struct_decl(is_anon bool) ast.StructDecl {
 	mut implements_types := []ast.TypeNode{cap: 3} // ast.void_type
 	mut last_line := p.prev_tok.pos().line_nr + 1
 	mut end_comments := []ast.Comment{}
+	mut has_option := false
 	if !no_body {
 		if p.tok.kind == .key_implements {
 			is_implements = true
@@ -253,6 +254,7 @@ fn (mut p Parser) struct_decl(is_anon bool) ast.StructDecl {
 				field_pos = field_start_pos.extend(p.prev_tok.pos())
 				if typ.has_option_or_result() {
 					option_pos = p.peek_token(-2).pos()
+					has_option = true
 				}
 			}
 			// Comments after type (same line)
@@ -372,6 +374,7 @@ fn (mut p Parser) struct_decl(is_anon bool) ast.StructDecl {
 			generic_types: generic_types
 			attrs:         attrs
 			is_anon:       is_anon
+			has_option:    has_option
 		}
 		is_pub:   is_pub
 	}
diff --git a/vlib/v/tests/options/option_struct_init_on_if_test.v b/vlib/v/tests/options/option_struct_init_on_if_test.v
new file mode 100644
index 000000000..76b691f1a
--- /dev/null
+++ b/vlib/v/tests/options/option_struct_init_on_if_test.v
@@ -0,0 +1,36 @@
+struct Number {
+	natural ?string
+	integer string
+}
+
+fn number(n int) Number {
+	return if n >= 0 { // a single return here
+		Number{
+			natural: '${n}'
+			integer: '${n}'
+		}
+	} else {
+		Number{
+			integer: '${n}'
+		}
+	}
+}
+
+fn test_main() {
+	mut ret := []Number{}
+	for n in [1, 0, -1] {
+		ret << number(n)
+	}
+	assert ret[0] == Number{
+		natural: ?string('1')
+		integer: '1'
+	}
+	assert ret[1] == Number{
+		natural: ?string('0')
+		integer: '0'
+	}
+	assert ret[2] == Number{
+		natural: ?string(none)
+		integer: '-1'
+	}
+}
-- 
2.39.5