pi-lens/rules/tree-sitter-queries/typescript/no-jump-in-finally.yml

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# Control-flow jump in a finally block
# A return/break/continue/throw in finally overrides the try/catch outcome.
id: no-jump-in-finally
name: Control-flow jump in finally block
severity: warning
category: bug
inline_tier: warning
language: typescript

message: "return/break/continue/throw in finally overrides the try/catch result and silently swallows exceptions"

description: |
  A return, break, continue, or throw inside a finally block replaces any value
  or exception propagating from the try/catch — so thrown errors disappear and
  returned values are overwritten, often silently.

  ❌  try { return compute(); } finally { return cleanup(); }  // always returns cleanup()
  ✅  try { return compute(); } finally { cleanup(); }

  Move the control-flow statement out of finally. (Matches jumps written
  directly in the finally block; jumps buried inside nested blocks are not
  flagged to keep this check false-positive-free.)

query: |
  (finally_clause
    (statement_block
      [
        (return_statement)
        (break_statement)
        (continue_statement)
        (throw_statement)
      ] @JUMP))

metavars:
  - JUMP

has_fix: false

tags:
  - bug
  - error-handling

examples:
  bad: |
    try { return doWork(); } finally { return cleanup(); }
  good: |
    try { return doWork(); } finally { cleanup(); }