Fix bug of [*] [**] {**} (*)

lib/katakata_irb/type_analyzer.rb

@@ -172,6 +172,8 @@ def evaluate_hash(node, scope)
         keys << evaluate(assoc.key, scope)
         values << evaluate(assoc.value, scope)
       when Prism::AssocSplatNode
+        next unless assoc.value # def f(**); {**}
+
         hash = evaluate assoc.value, scope
         unless hash.is_a?(KatakataIrb::Types::InstanceType) && hash.klass == Hash
           hash = method_call hash, :to_hash, [], nil, nil, scope
@@ -461,7 +463,6 @@ def evaluate_multi_write_node(node, scope)
       elsif node.value
         evaluate node.value, scope
       else
-        # For syntax invalid code like `(*a).b`
         KatakataIrb::Types::NIL
       end
     )
@@ -854,7 +855,7 @@ def assign_required_parameter(node, value, scope)
       end
     when :splat_node
       splat_value = value ? KatakataIrb::Types.array_of(value) : KatakataIrb::Types::ARRAY
-      assign_required_parameter node.expression, splat_value, scope
+      assign_required_parameter node.expression, splat_value, scope if node.expression
     end
   end
 
@@ -1032,7 +1033,7 @@ def evaluate_write(node, value, scope, evaluated_receivers)
     when Prism::CallNode
       evaluated_receivers&.[](node.receiver) || evaluate(node.receiver, scope) if node.receiver
     when Prism::SplatNode
-      evaluate_write node.expression, KatakataIrb::Types.array_of(value), scope, evaluated_receivers
+      evaluate_write node.expression, KatakataIrb::Types.array_of(value), scope, evaluated_receivers if node.expression
     when Prism::LocalVariableTargetNode, Prism::GlobalVariableTargetNode, Prism::InstanceVariableTargetNode, Prism::ClassVariableTargetNode, Prism::ConstantTargetNode
       scope[node.name.to_s] = value
     when Prism::ConstantPathTargetNode
@@ -1083,13 +1084,15 @@ def evaluate_multi_write_receiver(node, scope, evaluated_receivers)
   def evaluate_list_splat_items(list, scope)
     items = list.flat_map do |node|
       if node.is_a? Prism::SplatNode
+        next unless node.expression # def f(*); [*]
+
         splat = evaluate node.expression, scope
         array_elem, non_array = partition_to_array splat.nonnillable, :to_a
         [*array_elem, *non_array]
       else
         evaluate node, scope
       end
-    end.uniq
+    end.compact.uniq
     KatakataIrb::Types::UnionType[*items]
   end
 

test/test_type_analyze.rb

@@ -356,6 +356,7 @@ def test_def
     assert_call('def (a="").f; end; a.', include: String)
     assert_call('def f(a=1); a.', include: Integer)
     assert_call('def f(**nil); 1.', include: Integer)
+    assert_call('def f((*),*); 1.', include: Integer)
     assert_call('def f(a,*b); b.', include: Array)
     assert_call('def f(a,x:1); x.', include: Integer)
     assert_call('def f(a,x:,**); 1.', include: Integer)
@@ -366,6 +367,8 @@ def test_def
     assert_call('def f(a,...); 1.', include: Integer)
     assert_call('def f(...); g(...); 1.', include: Integer)
     assert_call('def f(*,**,&); g(*,**,&); 1.', include: Integer)
+    assert_call('def f(*,**,&); {**}.', include: Hash)
+    assert_call('def f(*,**,&); [*,**].', include: Array)
     assert_call('class Array; def f; self.', include: Array)
   end
 
@@ -465,6 +468,7 @@ def test_literal
     assert_call('true.', include: TrueClass)
     assert_call('false.', include: FalseClass)
     assert_call('nil.', include: NilClass)
+    assert_call('().', include: NilClass)
     assert_call('//.', include: Regexp)
     assert_call('/#{a=1}/.', include: Regexp)
     assert_call('/#{a=1}/; a.', include: Integer)
@@ -569,6 +573,7 @@ def test_while_until
   def test_for
     assert_call('for i in [1,2,3]; i.', include: Integer)
     assert_call('for i,j in [1,2,3]; i.', include: Integer)
+    assert_call('for *,(*) in [1,2,3]; 1.', include: Integer)
     assert_call('for *i in [1,2,3]; i.sample.', include: Integer)
     assert_call('for (a=1).b in [1,2,3]; a.', include: Integer)
     assert_call('for Array::B in [1,2,3]; Array::B.', include: Integer)