From e912854e9e71aa04a7dae9ba947fa919dfdbbaf8 Mon Sep 17 00:00:00 2001
From: Felipe Pena <felipensp@gmail.com>
Date: Thu, 3 Apr 2025 10:21:42 -0300
Subject: [PATCH] checker, cgen: fix selector option unwrapping on infix (fix
 #24108) (#24115)

---
 vlib/v/checker/if.v                           |  3 +-
 vlib/v/gen/c/cgen.v                           |  3 +-
 vlib/v/tests/loops/for_smartcast_test.v       |  2 +-
 vlib/v/tests/options/option_if_unwrap_test.v  | 54 +++++++++++++++++++
 vlib/v/tests/options/option_ptr_unwrap_test.v |  4 +-
 .../option_struct_init_with_ref_opt_test.v    |  2 +-
 vlib/v/type_resolver/comptime_resolver.v      |  5 ++
 7 files changed, 67 insertions(+), 6 deletions(-)
 create mode 100644 vlib/v/tests/options/option_if_unwrap_test.v

diff --git a/vlib/v/checker/if.v b/vlib/v/checker/if.v
index 543cfb7f4..e33801af5 100644
--- a/vlib/v/checker/if.v
+++ b/vlib/v/checker/if.v
@@ -691,7 +691,8 @@ fn (mut c Checker) smartcast_if_conds(mut node ast.Expr, mut scope ast.Scope, co
 		mut first_cond := control_expr.branches[0].cond
 		// handles unwrapping on if var == none { /**/ } else { /*unwrapped var*/ }
 		if mut first_cond is ast.InfixExpr {
-			if first_cond.left is ast.Ident && first_cond.op == .eq && first_cond.right is ast.None {
+			if first_cond.left in [ast.Ident, ast.SelectorExpr] && first_cond.op == .eq
+				&& first_cond.right is ast.None {
 				if c.comptime.get_ct_type_var(first_cond.left) == .smartcast {
 					first_cond.left_type = c.type_resolver.get_type(first_cond.left)
 					c.smartcast(mut first_cond.left, first_cond.left_type, first_cond.left_type.clear_flag(.option), mut
diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index 83181ab0e..2850c1112 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -4185,7 +4185,8 @@ fn (mut g Gen) selector_expr(node ast.SelectorExpr) {
 					for i, typ in field.smartcasts {
 						if i == 0 && (is_option_unwrap || nested_unwrap) {
 							deref := if g.inside_selector {
-								if is_iface_or_sumtype {
+								if is_iface_or_sumtype || (field.orig_type.is_ptr() && g.left_is_opt
+									&& is_option_unwrap) {
 									'*'.repeat(field.smartcasts.last().nr_muls())
 								} else {
 									'*'.repeat(field.smartcasts.last().nr_muls() + 1)
diff --git a/vlib/v/tests/loops/for_smartcast_test.v b/vlib/v/tests/loops/for_smartcast_test.v
index 393a0652d..ea327cb92 100644
--- a/vlib/v/tests/loops/for_smartcast_test.v
+++ b/vlib/v/tests/loops/for_smartcast_test.v
@@ -16,7 +16,7 @@ fn test_nested_sumtype_selector() {
 		pos: 1
 	}))}
 	for c.node is Expr {
-		assert typeof(c.node).name == 'Node'
+		assert typeof(c.node).name == 'Expr'
 		break
 	}
 }
diff --git a/vlib/v/tests/options/option_if_unwrap_test.v b/vlib/v/tests/options/option_if_unwrap_test.v
new file mode 100644
index 000000000..7e41fe191
--- /dev/null
+++ b/vlib/v/tests/options/option_if_unwrap_test.v
@@ -0,0 +1,54 @@
+fn unwrap(a ?[3]u8) {
+	if a == none {
+		println('${@FN}:${@LINE}: ${typeof(a).name}')
+		assert typeof(a).name == '?[3]u8'
+	} else {
+		println('${@FN}:${@LINE}: ${typeof(a).name}')
+		assert typeof(a).name == '[3]u8'
+	}
+	if a != none {
+		println('${@FN}:${@LINE}: ${typeof(a).name}')
+		assert typeof(a).name == '[3]u8'
+	} else {
+		println('${@FN}:${@LINE}: ${typeof(a).name}')
+		assert typeof(a).name == '?[3]u8'
+	}
+}
+
+struct Opt {
+pub mut:
+	f ?[3]u8
+}
+
+fn unwrap_field(opt Opt) {
+	if opt.f == none {
+		println('${@FN}:${@LINE}: ${typeof(opt.f).name}')
+		assert opt.f == ?[3]u8(none)
+		assert typeof(opt.f).name == '?[3]u8'
+	} else {
+		println('${@FN}:${@LINE}: ${typeof(opt.f).name}')
+		assert opt.f == [u8(2), 2, 2]!
+		assert typeof(opt.f).name == '[3]u8'
+	}
+	if opt.f != none {
+		println('${@FN}:${@LINE}: ${typeof(opt.f).name}')
+		assert opt.f == [u8(2), 2, 2]!
+		assert typeof(opt.f).name == '[3]u8'
+	} else {
+		println('${@FN}:${@LINE}: ${typeof(opt.f).name}')
+		assert opt.f == ?[3]u8(none)
+		assert typeof(opt.f).name == '?[3]u8'
+	}
+}
+
+fn test_main() {
+	mut a := ?[3]u8(none)
+	unwrap(a)
+	a = [3]u8{init: 1}
+	unwrap(a)
+
+	mut f := Opt{}
+	unwrap_field(f)
+	f.f = [3]u8{init: 2}
+	unwrap_field(f)
+}
diff --git a/vlib/v/tests/options/option_ptr_unwrap_test.v b/vlib/v/tests/options/option_ptr_unwrap_test.v
index d0334e8b4..4e10a054a 100644
--- a/vlib/v/tests/options/option_ptr_unwrap_test.v
+++ b/vlib/v/tests/options/option_ptr_unwrap_test.v
@@ -27,9 +27,9 @@ fn (mut li LinkedList[T]) add[T](data T) ? {
 		node.prev = node
 	} else {
 		node.next = li.head
-		node.prev = li.head?.prev
+		node.prev = li.head.prev
 		node.prev?.next = node
-		li.head?.prev = node
+		li.head.prev = node
 	}
 
 	li.size += 1
diff --git a/vlib/v/tests/options/option_struct_init_with_ref_opt_test.v b/vlib/v/tests/options/option_struct_init_with_ref_opt_test.v
index b618ff9c2..d9d0d0e64 100644
--- a/vlib/v/tests/options/option_struct_init_with_ref_opt_test.v
+++ b/vlib/v/tests/options/option_struct_init_with_ref_opt_test.v
@@ -31,7 +31,7 @@ pub fn (mut l LinkedList) pop() int {
 		l.head = none
 		l.tail = none
 	} else { // multiple elements
-		mut prev := tail.prev or { panic('prev cannot be none at this point') }
+		mut prev := tail.prev
 		prev.next = none
 		l.tail = prev
 	}
diff --git a/vlib/v/type_resolver/comptime_resolver.v b/vlib/v/type_resolver/comptime_resolver.v
index 53de0f516..e3eed8a58 100644
--- a/vlib/v/type_resolver/comptime_resolver.v
+++ b/vlib/v/type_resolver/comptime_resolver.v
@@ -75,6 +75,11 @@ pub fn (mut t TypeResolver) typeof_type(node ast.Expr, default_type ast.Type) as
 		if node.expr is ast.Ident && node.is_field_typ {
 			return t.get_type_from_comptime_var(node.expr)
 		}
+		if field := node.scope.find_struct_field(node.expr.str(), node.expr_type, node.field_name) {
+			if field.smartcasts.len > 0 {
+				return field.smartcasts.last()
+			}
+		}
 		sym := t.table.sym(t.resolver.unwrap_generic(node.expr_type))
 		if f := t.table.find_field_with_embeds(sym, node.field_name) {
 			return f.typ
-- 
2.39.5