[Fix rubocop#8869] Fix a false positive for Style/RedundantBegin

Fixes rubocop#8869.

This PR fixes a false positive for `Style/RedundantBegin`
when using `begin` for or assignment and method call.

CHANGELOG.md

@@ -6,6 +6,7 @@
 
 * [#8782](https://github.com/rubocop-hq/rubocop/issues/8782): Fix incorrect autocorrection for `Style/TernaryParentheses` with `defined?`. ([@dvandersluis][])
 * [#8864](https://github.com/rubocop-hq/rubocop/issues/8864): Fix false positive for `Style/RedundantBegin` with a postfix `while` or `until`. ([@dvandersluis][])
+* [#8869](https://github.com/rubocop-hq/rubocop/issues/8869): Fix a false positive for `Style/RedundantBegin` when using `begin` for or assignment and method call. ([@koic][])
 
 ## 0.93.0 (2020-10-08)
 

lib/rubocop/cop/style/redundant_begin.rb

@@ -85,8 +85,7 @@ def on_block(node)
         end
 
         def on_kwbegin(node)
-          return if node.parent&.assignment?
-          return if node.parent&.post_condition_loop?
+          return if node.each_ancestor.any?(&:assignment?) || node.parent&.post_condition_loop?
 
           first_child = node.children.first
           return if first_child.rescue_type? || first_child.ensure_type?

spec/rubocop/cop/style/redundant_begin_spec.rb

@@ -222,6 +222,17 @@ def method
     RUBY
   end
 
+  it 'does not register an offense when using `begin` for or assignment and method call' do
+    expect_no_offenses(<<~RUBY)
+      var ||= begin
+        foo
+        bar
+      end.baz do
+        qux
+      end
+    RUBY
+  end
+
   context '< Ruby 2.5', :ruby24 do
     it 'accepts a do-end block with a begin-end' do
       expect_no_offenses(<<~RUBY)