Merge pull request rubocop#10277 from koic/fix_incorrect_autocorrect_…

…for_style_redundant_interpolation

[Fix rubocop#10276] Fix an incorrect autocorrect for `Style/RedundantInterpolation`

changelog/fix_incorrect_autocorrect_for_style_redundant_interpolation.md

@@ -0,0 +1 @@
+* [#10276](https://github.com/rubocop/rubocop/issues/10276): Fix an incorrect autocorrect for `Style/RedundantInterpolation` when using a method call without parentheses in string interpolation. ([@koic][])

lib/rubocop/cop/style/redundant_interpolation.rb

@@ -82,10 +82,20 @@ def autocorrect_variable_interpolation(corrector, embedded_node, node)
         end
 
         def autocorrect_single_variable_interpolation(corrector, embedded_node, node)
-          variable_loc = embedded_node.children.first.loc
-          replacement = "#{variable_loc.expression.source}.to_s"
+          embedded_var = embedded_node.children.first
 
-          corrector.replace(node, replacement)
+          source = if require_parentheses?(embedded_var)
+                     receiver = range_between(
+                       embedded_var.loc.expression.begin_pos, embedded_var.loc.selector.end_pos
+                     )
+                     arguments = embedded_var.arguments.map(&:source).join(', ')
+
+                     "#{receiver.source}(#{arguments})"
+                   else
+                     embedded_var.source
+                   end
+
+          corrector.replace(node, "#{source}.to_s")
         end
 
         def autocorrect_other(corrector, embedded_node, node)
@@ -97,6 +107,10 @@ def autocorrect_other(corrector, embedded_node, node)
           corrector.replace(embedded_loc.begin, '(')
           corrector.replace(embedded_loc.end, ').to_s')
         end
+
+        def require_parentheses?(node)
+          node.send_type? && !node.arguments.count.zero? && !node.parenthesized_call?
+        end
       end
     end
   end

spec/rubocop/cop/style/redundant_interpolation_spec.rb

@@ -177,6 +177,28 @@
     RUBY
   end
 
+  it 'registers an offense for "#{do_something 42}"' do
+    expect_offense(<<~'RUBY')
+      "#{do_something 42}"
+      ^^^^^^^^^^^^^^^^^^^^ Prefer `to_s` over string interpolation.
+    RUBY
+
+    expect_correction(<<~'RUBY')
+      do_something(42).to_s
+    RUBY
+  end
+
+  it 'registers an offense for "#{foo.do_something 42}"' do
+    expect_offense(<<~'RUBY')
+      "#{foo.do_something 42}"
+      ^^^^^^^^^^^^^^^^^^^^^^^^ Prefer `to_s` over string interpolation.
+    RUBY
+
+    expect_correction(<<~'RUBY')
+      foo.do_something(42).to_s
+    RUBY
+  end
+
   it 'registers an offense for "#{var}"' do
     expect_offense(<<~'RUBY')
       var = 1; "#{var}"