Panic on a pending inline snapshot when the code moves

[max-sixty]

What happened?

When there's a pending inline snapshot and the code changes such that the line moves, running cargo insta test panics with:

thread 'main' panicked at 'Could not find snapshot in line 109', /Users/maximilian/.cargo/registry/src/github.com-1ecc6299db9ec823/cargo-insta-1.13.0/src/inline.rs:66:21
stack backtrace:
   0:        0x102d73d88 - std::backtrace_rs::backtrace::libunwind::trace::hbad44c2b21d61f40
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:        0x102d73d88 - std::backtrace_rs::backtrace::trace_unsynchronized::h664423984da6366c
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:        0x102d73d88 - std::sys_common::backtrace::_print_fmt::ha0bed729b1de74e6
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/sys_common/backtrace.rs:67:5
   3:        0x102d73d88 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h58c637f9e30d1b8a
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/sys_common/backtrace.rs:46:22
   4:        0x102d93a60 - core::fmt::write::hc16ca97d9f5e0acd
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/core/src/fmt/mod.rs:1168:17
   5:        0x102d6f1b8 - std::io::Write::write_fmt::hd53dc7153ccce04d
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/io/mod.rs:1660:15
   6:        0x102d765ec - std::sys_common::backtrace::_print::h52e9a34b49f28ab7
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/sys_common/backtrace.rs:49:5
   7:        0x102d765ec - std::sys_common::backtrace::print::h0bf7306c450cdde6
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/sys_common/backtrace.rs:36:9
   8:        0x102d765ec - std::panicking::default_hook::{{closure}}::ha41f2cf175ca93cf
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/panicking.rs:211:50
   9:        0x102d76194 - std::panicking::default_hook::h838498b157804a1a
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/panicking.rs:228:9
  10:        0x102d76bb0 - std::panicking::rust_panic_with_hook::h7722806c30430655
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/panicking.rs:606:17
  11:        0x102d76920 - std::panicking::begin_panic_handler::{{closure}}::h265229fa7cad6de7
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/panicking.rs:502:13
  12:        0x102d74254 - std::sys_common::backtrace::__rust_end_short_backtrace::hfa83d61d0ed14557
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/sys_common/backtrace.rs:139:18
  13:        0x102d76688 - rust_begin_unwind
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/panicking.rs:498:5
  14:        0x102da6008 - core::panicking::panic_fmt::hd3f68d55261c2af0
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/core/src/panicking.rs:116:14
  15:        0x102b672a4 - cargo_insta::inline::FilePatcher::add_snapshot_macro::h8a79f97c8f49c2fe
  16:        0x102b1da70 - cargo_insta::cargo::SnapshotContainer::load::h274867ffb5783729
  17:        0x102b209c8 - core::ops::function::impls::<impl core::ops::function::FnMut<A> for &mut F>::call_mut::hfb6e5615a426443f
  18:        0x102b3ab90 - <core::iter::adapters::filter_map::FilterMap<I,F> as core::iter::traits::iterator::Iterator>::next::h183f1bfea2264370
  19:        0x102b311a8 - cargo_insta::cli::load_snapshot_containers::hf409b9dd856c3707
  20:        0x102b31a94 - cargo_insta::cli::process_snapshots::h397828296feac642
  21:        0x102b34210 - cargo_insta::cli::test_run::h9b83dbd1e984526b
  22:        0x102b38acc - cargo_insta::cli::run::h7b33cc41a7ac66db
  23:        0x102b3be9c - cargo_insta::main::hc514b8cc9ffa638d
  24:        0x102b3f3ac - std::sys_common::backtrace::__rust_begin_short_backtrace::h28a0262009a3684a
  25:        0x102b6cbe4 - std::rt::lang_start::{{closure}}::h008ec206a5775c7d
  26:        0x102d73574 - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::hba09dfad0460fd87
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/core/src/ops/function.rs:259:13
  27:        0x102d73574 - std::panicking::try::do_call::h4ce3f7a5c9aef539
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/panicking.rs:406:40
  28:        0x102d73574 - std::panicking::try::hd24b5077d4e7cf4f
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/panicking.rs:370:19
  29:        0x102d73574 - std::panic::catch_unwind::h7e4545d59021a7e8
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/panic.rs:133:14
  30:        0x102d73574 - std::rt::lang_start_internal::{{closure}}::h84dbc49308bdb431
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/rt.rs:128:48
  31:        0x102d73574 - std::panicking::try::do_call::h72e6b5f705f91e0a
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/panicking.rs:406:40
  32:        0x102d73574 - std::panicking::try::hb85264d1d4244b1a
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/panicking.rs:370:19
  33:        0x102d73574 - std::panic::catch_unwind::h202929673dde26bb
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/panic.rs:133:14
  34:        0x102d73574 - std::rt::lang_start_internal::h0c28bd035905a2f7
                               at /rustc/9d1b2106e23b1abd32fce1f17267604a5102f57a/library/std/src/rt.rs:128:20
  35:        0x102b3f460 - _main
[[Command exited with 101]]

I get this quite often since I generally leave on:

RUST_BACKTRACE=1 watchexec -c -e rs,pest -- cargo +nightly insta test --accept

...and so whenever there's a test that doesn't pass, and a snapshot changes, the snapshot stays pending, and adding or removing code which changes a line will then cause a panic.

I realize i haven't been involved much in development since the early days of 0.11.0 (!). But after I've finished the latest version of my current project, I could take this, if no one else does.

Reproduction steps

1. Write inline test
2. Run cargo insta test
3. Before reviewing, add a line to the code such that the inline test changes line
4. Run cargo insta test

Insta Version

1.13.0

rustc Version

1.59.0

What did you expect?

Probably deleting the out-of-date snapshot, maybe with a warning.

Maaaybe there's a case for an error, I wouldn't advocate for that though.