Fix heredoc content and closing identifier being removed in method call arguments

[fs0414]

📋 Summary

Fixes a bug where heredoc content and closing identifiers were incorrectly removed when heredocs were used as method call arguments (e.g., puts(<<~HEREDOC)).

Root cause: The extract_location method in prism_bridge.rb only checked direct child nodes for closing_loc. When heredocs appear as method call arguments, they are grandchild nodes nested under ArgumentsNode, so they were not detected.

🔧 Changes

🐛 Bug Fix (lib/rfmt/prism_bridge.rb)

• Recursive closing_loc search: Replaced the direct child-only check with a new find_max_closing_loc_recursive method that traverses all descendant nodes
• Depth guard: Recursion is capped at depth 10 to prevent infinite traversal
• Backwards compatible: The recursive approach is a superset of the previous logic — it handles both Issue [Bug]: Heredoc content and closing identifier are removed #74 (direct children) and Issue [Bug]: Heredoc content and terminator are incorrectly removed #86 (deeper nesting)

🧪 Tests (spec/rfmt_spec.rb)

• Multiple heredocs as arguments: puts(<<~HEREDOC, <<~HEREDOC2)
• Single heredoc as argument: puts(<<~HEREDOC)
• Heredoc with method chain: foo.bar(<<~SQL)

🗂️ Changed Files

• Core: lib/rfmt/prism_bridge.rb
• Tests: spec/rfmt_spec.rb

🧪 Tests

How to run

bundle exec rspec spec/rfmt_spec.rb -e "Issue #86" --format documentation

Results

• 90 examples, 0 failures (full suite)
• 3 new test cases for Issue [Bug]: Heredoc content and terminator are incorrectly removed #86

Verification

• Multiple heredocs in method call arguments preserved
• Single heredoc in method call argument preserved
• Heredoc with method chain preserved
• Existing heredoc tests (Issue [Bug]: Heredoc content and closing identifier are removed #74) still pass
• Full test suite passes
• RuboCop passes with no offenses

📦 Breaking Changes

None

Related Issue

Closes #86