Fix inconsistent evaluation of keyword splat (#10959)

[Bug #20180]

Backports #9624.

2 files changed, 21 insertions, 1 deletions

diff --git a/compile.c b/compile.c
index 3c92729760..a938d58abb 100644
--- a/compile.c
+++ b/compile.c
@@ -4826,7 +4826,12 @@ compile_array_1(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *node)
     }
     else {
         CHECK(COMPILE_(ret, "array element", node, FALSE));
-        ADD_INSN1(ret, node, newarray, INT2FIX(1));
+        if (keyword_node_p(node)) {
+            ADD_INSN1(ret, node, newarraykwsplat, INT2FIX(1));
+        }
+        else {
+            ADD_INSN1(ret, node, newarray, INT2FIX(1));
+        }
     }
 
     return 1;
diff --git a/test/ruby/test_syntax.rb b/test/ruby/test_syntax.rb
index 2d4ce59b39..a7a25ef3c0 100644
--- a/test/ruby/test_syntax.rb
+++ b/test/ruby/test_syntax.rb
@@ -233,6 +233,7 @@ class TestSyntax < Test::Unit::TestCase
   def test_array_kwsplat_hash
     kw = {}
     h = {a: 1}
+    a = []
     assert_equal([], [**{}])
     assert_equal([], [**kw])
     assert_equal([h], [**h])
@@ -247,6 +248,20 @@ class TestSyntax < Test::Unit::TestCase
     assert_equal([1, kw], [1, kw])
     assert_equal([1, h], [1, h])
 
+    assert_equal([], [*a, **{}])
+    assert_equal([], [*a, **kw])
+    assert_equal([h], [*a, **h])
+    assert_equal([{}], [*a, {}])
+    assert_equal([kw], [*a, kw])
+    assert_equal([h], [*a, h])
+
+    assert_equal([1], [1, *a, **{}])
+    assert_equal([1], [1, *a, **kw])
+    assert_equal([1, h], [1, *a, **h])
+    assert_equal([1, {}], [1, *a, {}])
+    assert_equal([1, kw], [1, *a, kw])
+    assert_equal([1, h], [1, *a, h])
+
     assert_equal([], [**kw, **kw])
     assert_equal([], [**kw, **{}, **kw])
     assert_equal([1], [1, **kw, **{}, **kw])