Null pointer when running code2prompt from CLI with LC_ALL unset

[superandoni]

Installed code2prompt 3.0.2 via homebrew on MacOS X Sequoia 15.4.1 on a M1 Macbook Pro.

My output of locale:

LANG="en_UK.UTF-8"
LC_COLLATE="C"
LC_CTYPE="C"
LC_MESSAGES="C"
LC_MONETARY="C"
LC_NUMERIC="C"
LC_TIME="C"
LC_ALL=

Running code2prompt in any folder gives the following error:

▹▹▹▹▸ Done!
thread 'main' panicked at crates/code2prompt/src/main.rs:182:89:
called `Result::unwrap()` on an `Err` value: Error { kind: SystemInvalidReturn { function_name: "newlocale", message: "newlocale unexpectedly returned a null pointer." } }
stack backtrace:
   0:        0x102db5d58 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::he95167bc0db69172
   1:        0x102c2920c - core::fmt::write::h7a9b1a2c5a4d720d
   2:        0x102d9d068 - std::io::Write::write_fmt::h6ba1180d709be9ef
   3:        0x102db5c18 - std::sys::backtrace::BacktraceLock::print::he986caf53af0c7c0
   4:        0x102dbb17c - std::panicking::default_hook::{{closure}}::h91abe66414d5ff97
   5:        0x102dbb08c - std::panicking::default_hook::hd88a7d3ab5420733
   6:        0x102dbb700 - std::panicking::rust_panic_with_hook::h0c4570804070c568
   7:        0x102db615c - std::panicking::begin_panic_handler::{{closure}}::h137406384c01ca5e
   8:        0x102db5fa0 - std::sys::backtrace::__rust_end_short_backtrace::hbbf6c8bb05b960c8
   9:        0x102dbb218 - _rust_begin_unwind
  10:        0x102e4659c - core::panicking::panic_fmt::h8df0ae8acbd1e44d
  11:        0x102e464ec - core::result::unwrap_failed::h724a6477a0a39f8d
  12:        0x102c0933c - code2prompt::main::h5a9036ecf9c28fb2
[2]    28425 abort      RUST_BACKTRACE=full code2prompt .

Workaround found by explicitly setting LC_ALL:
LC_ALL="C" code2prompt .

[ODAncona]

Hi @superandoni,

Does this issue still arise with the latest version ?

I was unable to reproduce it with my Linux

olivier@RocketPC:~/projet/code2prompt/crates$ LANG="en_UK.UTF-8" \
LC_COLLATE="C" \
LC_CTYPE="C" \
LC_MESSAGES="C" \
LC_MONETARY="C" \
LC_NUMERIC="C" \
LC_TIME="C" \
LC_ALL= \
code2prompt .
▹▹▹▹▸ Done!                                                                                                                                                                             [i] Token count: 98564, Model info: ChatGPT models, text-embedding-ada-002
[✓] Copied to clipboard successfully.

[superandoni]

Yes, still failing on version 4.0.2, despite my current locale command output now being:

LANG="en_UK.UTF-8"
LC_COLLATE="C"
LC_CTYPE="C"
LC_MESSAGES="C"
LC_MONETARY="C"
LC_NUMERIC="C"
LC_TIME="C"
LC_ALL="C"

The workaround of running LC_ALL="C" code2prompt . still works fine.

Current error trace:

❯ RUST_BACKTRACE=full code2prompt .
▹▹▹▹▸ Done!
thread 'main' panicked at crates/code2prompt/src/main.rs:162:89:
called `Result::unwrap()` on an `Err` value: Error { kind: SystemInvalidReturn { function_name: "newlocale", message: "newlocale unexpectedly returned a null pointer." } }
stack backtrace:
   0:        0x10309c32c - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::h9e223a7170c87c9b
   1:        0x102ee9ed0 - core::fmt::write::hf208100295273523
   2:        0x103071e94 - std::io::Write::write_fmt::h5f2b208c86ba2551
   3:        0x10309c1ec - std::sys::backtrace::BacktraceLock::print::h1c8ca659c64c79a6
   4:        0x103084e58 - std::panicking::default_hook::{{closure}}::h00ab63c517aa9bf7
   5:        0x103084d54 - std::panicking::default_hook::h7114060274cbd9c1
   6:        0x103085408 - std::panicking::rust_panic_with_hook::hf568cae7cf253602
   7:        0x10309c834 - std::panicking::begin_panic_handler::{{closure}}::h8ca8cc2ff429dfd9
   8:        0x10309c564 - std::sys::backtrace::__rust_end_short_backtrace::h43a9189ff310312a
   9:        0x103084f58 - __rustc[75b86e412cc6dff0]::rust_begin_unwind
  10:        0x10314e0f4 - core::panicking::panic_fmt::h7ed32a806317de14
  11:        0x10314e42c - core::result::unwrap_failed::h49d0e59be965fa97
  12:        0x102ebacc4 - code2prompt::run_cli_mode_with_args::{{closure}}::hacabd29f4d6cd444
  13:        0x102ec1f0c - code2prompt::main::{{closure}}::h2665ca49b3654326
  14:        0x102ebff28 - code2prompt::main::h99f0cac01f107470
[1]    24922 abort      RUST_BACKTRACE=full code2prompt .

Now on MacOS 15.6.1 and zsh 5.9 (arm64-apple-darwin24.0)