Fix false positive for Style/EmptyLiteral with Hash.new([])

The first parameter for Hash.new is the default value: ```rb Hash.new([])[:foo] # => [] ``` Side note: this usage is most likely a programming error. You want the block form where different keys _don't_ share the same underlying array.
rubocop · Sep 1, 2024 · 60d3cd6 · 60d3cd6
1 parent 7bb9708
commit 60d3cd6
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diff --git a/changelog/fix_false_positive_empty_literal.md b/changelog/fix_false_positive_empty_literal.md
@@ -0,0 +1 @@
+* [#13178](https://github.com/rubocop/rubocop/pull/13178): Fix false positive for `Style/EmptyLiteral` with `Hash.new([])`. ([@earlopain][])
diff --git a/lib/rubocop/cop/style/empty_literal.rb b/lib/rubocop/cop/style/empty_literal.rb
@@ -34,7 +34,7 @@ class EmptyLiteral < Base
         def_node_matcher :array_node, '(send (const {nil? cbase} :Array) :new (array)?)'
 
         # @!method hash_node(node)
-        def_node_matcher :hash_node, '(send (const {nil? cbase} :Hash) :new (array)?)'
+        def_node_matcher :hash_node, '(send (const {nil? cbase} :Hash) :new)'
 
         # @!method str_node(node)
         def_node_matcher :str_node, '(send (const {nil? cbase} :String) :new)'

diff --git a/spec/rubocop/cop/style/empty_literal_spec.rb b/spec/rubocop/cop/style/empty_literal_spec.rb
@@ -78,7 +78,6 @@
       it_behaves_like 'registers_and_corrects', initializer: 'Hash.new()'
       it_behaves_like 'registers_and_corrects', initializer: 'Hash.new'
       it_behaves_like 'registers_and_corrects', initializer: '::Hash.new()'
-      it_behaves_like 'registers_and_corrects', initializer: 'Hash.new([])'
       it_behaves_like 'registers_and_corrects', initializer: 'Hash[]'
       it_behaves_like 'registers_and_corrects', initializer: 'Hash([])'
     end
@@ -107,6 +106,10 @@
       expect_no_offenses('test = ::Hash.new { block }')
     end
 
+    it 'does not register an offense for Hash.new([])' do
+      expect_no_offenses('Hash.new([])')
+    end
+
     context 'Ruby 2.7', :ruby27 do
       it 'does not register an offense for Hash.new { _1[_2] = [] }' do
         expect_no_offenses('test = Hash.new { _1[_2] = [] }')
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		* [#13178](https://github.com/rubocop/rubocop/pull/13178): Fix false positive for `Style/EmptyLiteral` with `Hash.new([])`. ([@earlopain][])