fix: use tmpfile to avoid bash 3.2 apostrophe bug in agent launcher#262
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imsickofmaps wants to merge 1 commit into
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fix: use tmpfile to avoid bash 3.2 apostrophe bug in agent launcher#262imsickofmaps wants to merge 1 commit into
imsickofmaps wants to merge 1 commit into
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macOS ships bash 3.2 which has a lexer bug: apostrophes inside heredoc content nested within \$(...) cause a syntax error. Replace the nested heredoc pattern with a tmpfile approach (top-level heredoc + cat) for AgentAider, AgentOpenCode, and the default case. AgentAmp is unaffected as it already uses top-level stdin piping. Adds a regression test case with apostrophes in the prompt. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Problem
writeAgentLaunchergeneratesstart.shscripts using a heredoc nested inside a$(...)command substitution:macOS ships bash 3.2 (GPL2 constraint). Bash 3.2 has a known lexer bug: when scanning ahead for the closing
)", it incorrectly tracks single-quote state across the heredoc body. Any apostrophe in the prompt —today's,don't,it's— causes:This silently breaks agent launch for any task description containing an apostrophe, which is extremely common.
Fix
Replace the nested heredoc with a tmpfile approach — write the prompt via a top-level heredoc (safe on all bash versions), then read it with a plain
$(cat "$TMPFILE"):Applied to
AgentAider,AgentOpenCode, and the default case.AgentAmpis unaffected — it already uses top-level stdin piping.A regression test case with apostrophes in the prompt is included, along with assertions that non-Amp scripts use the tmpfile pattern.
A note on provenance: I'm not a Go programmer — I'm just an avid and very happy Sidecar user who hit this bug. This fix was written with Claude Code (with me pointing it at the bug report and reviewing the output). I've done my best to follow the project's patterns and test conventions, but please scrutinise the diff accordingly. Happy to iterate if anything's off.