From 932ce048feb9f26bcd9e8dc93ada4d2a407ace1f Mon Sep 17 00:00:00 2001 From: Nobuyoshi Nakada Date: Fri, 5 Dec 2025 19:01:21 +0900 Subject: [Bug #21669] Implement void value expression check for `case`/`when` If the all `when` and `else` branches are void, the `case` is also void. --- parse.y | 12 ++++++++++++ test/ruby/test_syntax.rb | 24 ++++++++++++++++++++++++ 2 files changed, 36 insertions(+) diff --git a/parse.y b/parse.y index 7efc7a7ea5..63b6ab9b16 100644 --- a/parse.y +++ b/parse.y @@ -13864,6 +13864,18 @@ value_expr_check(struct parser_params *p, NODE *node) case NODE_RETRY: goto found; + case NODE_CASE: + case NODE_CASE2: + for (node = RNODE_CASE(node)->nd_body; + node && nd_type_p(node, NODE_WHEN); + node = RNODE_WHEN(node)->nd_next) { + if (!(vn = value_expr_check(p, RNODE_WHEN(node)->nd_body))) { + return NULL; + } + if (!void_node) void_node = vn; + } + break; + case NODE_CASE3: if (!RNODE_CASE3(node)->nd_body || !nd_type_p(RNODE_CASE3(node)->nd_body, NODE_IN)) { compile_error(p, "unexpected node"); diff --git a/test/ruby/test_syntax.rb b/test/ruby/test_syntax.rb index 9a14375056..3638d83e2b 100644 --- a/test/ruby/test_syntax.rb +++ b/test/ruby/test_syntax.rb @@ -2053,6 +2053,30 @@ eom }; end + def test_value_expr_in_case + assert_syntax_error("#{<<~"{#"}\n#{<<~'};'}", /void value expression/, nil, "#{BUG_21669} 1.3") + {# + x = + case a + when 1; return + when 2; return + else return + end + }; + end + + def test_value_expr_in_case2 + assert_syntax_error("#{<<~"{#"}\n#{<<~'};'}", /void value expression/, nil, "#{BUG_21669} 1.3") + {# + x = + case + when 1; return + when 2; return + else return + end + }; + end + def test_tautological_condition assert_valid_syntax("def f() return if false and invalid; nil end") assert_valid_syntax("def f() return unless true or invalid; nil end") -- cgit v1.2.3