Nondeterministic results for --convert-repetitions

[Mrmaxmeier]

$ git describe
v0.3.1
$ ./target/debug/grex -r "AAAAAA"
^A{6}$
$ ./target/debug/grex -r "AAAAAA"
thread 'main' panicked at 'assertion failed: end <= len', <::core::macros::panic macros>:3:10
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace.
$ ./target/debug/grex -r "AAAAAA"
thread 'main' panicked at 'assertion failed: end <= len', <::core::macros::panic macros>:3:10
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace.
$ ./target/debug/grex -r "AAAAAA"
^A{6}$
$ ./target/debug/grex -r "AAAAAA"
^(AA){4}A$
$ ./target/debug/grex -r "AAAAAA"
^(AAA){2}$

backtrace for reference

⋊> ~/_/_/grex $ ./target/debug/grex -r "AAAAAA"
thread 'main' panicked at 'assertion failed: end <= len', <::core::macros::panic macros>:3:10
stack backtrace:
   0: backtrace::backtrace::libunwind::trace
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.40/src/backtrace/libunwind.rs:88
   1: backtrace::backtrace::trace_unsynchronized
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.40/src/backtrace/mod.rs:66
   2: std::sys_common::backtrace::_print_fmt
             at src/libstd/sys_common/backtrace.rs:77
   3: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
             at src/libstd/sys_common/backtrace.rs:59
   4: core::fmt::write
             at src/libcore/fmt/mod.rs:1057
   5: std::io::Write::write_fmt
             at src/libstd/io/mod.rs:1426
   6: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:62
   7: std::sys_common::backtrace::print
             at src/libstd/sys_common/backtrace.rs:49
   8: std::panicking::default_hook::{{closure}}
             at src/libstd/panicking.rs:195
   9: std::panicking::default_hook
             at src/libstd/panicking.rs:215
  10: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:472
  11: rust_begin_unwind
             at src/libstd/panicking.rs:376
  12: core::panicking::panic_fmt
             at src/libcore/panicking.rs:84
  13: core::panicking::panic
             at src/libcore/panicking.rs:51
  14: alloc::vec::Vec<T>::drain
             at ./<::core::macros::panic macros>:2
  15: alloc::vec::Vec<T>::splice
             at /rustc/a9c1c04e986dbf610be8cbe6a8107f90b4db61ce/src/liballoc/vec.rs:2180
  16: grex::grapheme::GraphemeCluster::replace_graphemes_with_repetitions
             at src/grapheme.rs:204
  17: grex::grapheme::GraphemeCluster::convert_repetitions
             at src/grapheme.rs:53
  18: grex::regexp::RegExp::grapheme_clusters
             at src/regexp.rs:123
  19: grex::regexp::RegExp::from
             at src/regexp.rs:93
  20: grex::regexp::RegExpBuilder::build
             at src/regexp.rs:69
  21: grex::handle_input
             at src/main.rs:109
  22: grex::main
             at src/main.rs:77
  23: std::rt::lang_start::{{closure}}
             at /rustc/a9c1c04e986dbf610be8cbe6a8107f90b4db61ce/src/libstd/rt.rs:67
  24: std::rt::lang_start_internal::{{closure}}
             at src/libstd/rt.rs:52
  25: std::panicking::try::do_call
             at src/libstd/panicking.rs:296
  26: __rust_maybe_catch_panic
             at src/libpanic_unwind/lib.rs:79
  27: std::panicking::try
             at src/libstd/panicking.rs:272
  28: std::panic::catch_unwind
             at src/libstd/panic.rs:394
  29: std::rt::lang_start_internal
             at src/libstd/rt.rs:51
  30: std::rt::lang_start
             at /rustc/a9c1c04e986dbf610be8cbe6a8107f90b4db61ce/src/libstd/rt.rs:67
  31: main
  32: __libc_start_main
             at ../csu/libc-start.c:308
  33: _start
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

It looks like the behavior is caused by unstable output of GraphemeCluster::sort_repetitions, but the input seems wrong as well ("AA" * 4 != "AAAAAA"[0..5]):

[src/grapheme.rs:154] &sorted_repetitions = [
    Some((["A", "A", "A"], 0..6, 2)),
    Some((["A", "A"], 0..5, 4)),
    Some((["A"], 0..6, 6)),
]

[pemistahl]

Thanks for your bug report @Mrmaxmeier. It is just in time because I'm currently finishing version 0.3.2 which fixes these problems. Please try the new version. Closed.