Redirect after a list or pipeline attaches to the whole list instead of the last command #345

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1. fprochazka commented on Sep 19, 2026

   

   fprochazka

   on Sep 19, 2026

   More actions

   A pipe after the redirect makes this worse than misattribution — it changes pipeline membership.

   foo && cat f > out | head -80
   
   (program
     (pipeline
       (redirected_statement
         body: (list
           (command name: (command_name (word)))
           (command name: (command_name (word)) argument: (word)))
         redirect: (file_redirect destination: (word)))
       (command name: (command_name (word)) argument: (number))))
   

   The over-extended redirected_statement is now the first member of the pipeline, so the tree says (foo && cat f > out) | head -80. Bash binds the pipe tighter than && and runs foo && (cat f > out | head -80):

   $ false && echo hi | wc -l
   $ echo "exit=$?"
   exit=1
   

   Nothing is printed. Grouped the other way, wc -l would run and print 0.

   Without the redirect the same shape nests correctly:

   foo && cat f | head -80
   
   (program
     (list
       (command name: (command_name (word)))
       (pipeline
         (command name: (command_name (word)) argument: (word))
         (command name: (command_name (word)) argument: (number)))))
   

   And with the redirect on an earlier member rather than the last one it is also correct:

   foo > o && cat f | head -80
   
   (program
     (list
       (redirected_statement body: (command ...) redirect: (file_redirect ...))
       (pipeline (command ...) (command ...))))
   

   So the inversion needs three things together: an and-or list, a redirect on its last member, and a pipe after it. 2> behaves identically to > here, which matches bash — a redirect has no effect on pipeline shape.

   Seen on tree-sitter-bash 0.25.1 with the Python binding 0.25.2.
2. fprochazka

   added a commit that references this issue on Sep 19, 2026

   Attribute a redirect to the command it was written on

   ...

   d3b3610