Keep the end of long output, and pass the command line to _helpless - #246
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The typescript was capped with head -n 1024, keeping the start of the output. Errors are usually at the end (tracebacks, make: *** Error, segfaults), so a program that printed a lot and then failed lost its error before any helper or _helpless saw it. Now keep the first 64 lines (where the command line is echoed and found) plus the last 1024, with a marker for what was omitted. _helpless now also receives the command line as a second argument, so whatever explains the output (in cs50/codespace, the CS50 Duck via cs50.ai) can see what was run. The default _helpless ignores it; output stays the first argument, so the codespace's empty-output check is unaffected.
Nothing exercised _help50 itself: the head/tail cap and the new command-line argument were only checked by hand under a pty. Drive _help50 directly in the image instead, with a fabricated typescript and a fake _helpless, and assert that a command printing 3000 lines then an error yields the command line as the second argument and, as the first, output that starts at the program's first line, carries the omission marker, drops the middle, and ends with the error. Also check that a failed command with no output yields an empty first argument, which is what the codespace's empty-output check depends on. The check fails against the previous help50.sh.
hgarfer
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cs50/cli#246 passes the failed command's line to _helpless as a second argument. Include it, as a transcript ($ cmd, then output), so cs50.ai can see what the student ran, not just what came back.
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Reimplements help50 in Bash, running locally and automatically per login shell, without a server. Usage is inspired by systemctl: - help50 start/stop/status/enable/disable/is-enabled control a session that logs the shell's I/O via script to /tmp/help50.$PPID - help50 COMMAND [ARGS...] runs COMMAND as though typed directly, with the same exit status - HELP50_DISABLED in the environment is a kill switch, so that as a Codespaces secret help50 can be turned off fleet-wide without a rebuild /etc/profile.d/help50.sh installs a PROMPT_COMMAND hook that, after a failed command, strips the typescript of ANSI/control characters and terminal echo, bounds the read (first 64K + last 1M) and the output (first 64 + last 1,024 lines), and passes it to each executable helper in /opt/cs50/lib/help50/ under a 5-second timeout. Helper output is shown via _helpful; otherwise _helpless receives the output and command line (a no-op here, overridden in cs50/codespace to relay to the CS50 Duck). Also adds /opt/cs50/lib/cli helper functions (_alert, _ansi, _find, _fold, _sure) used by the make, sqlite3, http-server, and valgrind wrappers; helpers for bash, cd, clang, make, and python; tests/smoke.sh (make smoke), run in CI against each architecture's build before pushing to Docker Hub; and installs bsdextrautils, colorized-logs, file, expect, and fzf, dropping the Python help50 package. Squashed from 99 commits, including #244, #245, #246, #247, and #248. Co-authored-by: Rongxin Liu <10591665+rongxin-liu@users.noreply.github.com>
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Two improvements to what reaches the CS50 Duck when no helper matches, from testing on the canary codespace (cs50/codespace#196).
Keep the end of long output. The typescript was capped with
head -n 1024, i.e. the start of the output. Errors are usually at the end: tracebacks,make: *** Error, segfaults. A program that printed a few thousand lines and then crashed lost its error entirely, so neither the helpers nor_helplessever saw it. Now the first 64 lines are kept (the echoed command line lives there and is still found) plus the last 1024, with a[... N lines omitted ...]marker between them. Short output is unchanged.Pass the command line to
_helpless. cs50.ai's/api/v1/helpwraps whatever it receives in a code block and asks the model to explain it, but until now it only got the output, not what the student typed._helplessnow receives the command line as a second argument (_helpless OUTPUT CMD). The default_helplessignores it; output stays$1, so cs50/codespace's "empty output, nothing to explain" check is unaffected. The companion change that uses it is cs50/codespace#199.The hook contract is now documented above the default definitions in
help50.sh.Testing.
tests/smoke.shnow drives_help50directly in the image with a fabricated typescript and a fake_helpless: a command that prints 3000 lines and then fails yields./slowas the second argument and, as the first, output that starts at the program's first line, contains[... 1914 lines omitted ...], no longer contains the middle, and ends with the error; a failed command with no output yields an empty first argument. The check fails against the previoushelp50.sh. Also verified under a pty on the canary codespace:cat nothereyields$ cat nothere+ its error in the codespace payload.