[INFO] crate nixcfg 0.2.0 is already in cache
[INFO] extracting crate nixcfg 0.2.0 into work/ex/beta-1.38-1/sources/1.37.0/reg/nixcfg/0.2.0
[INFO] extracting crate nixcfg 0.2.0 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/nixcfg/0.2.0
[INFO] validating manifest of nixcfg-0.2.0 on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of nixcfg-0.2.0 on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing nixcfg-0.2.0
[INFO] finished frobbing nixcfg-0.2.0
[INFO] frobbed toml for nixcfg-0.2.0 written to work/ex/beta-1.38-1/sources/1.37.0/reg/nixcfg/0.2.0/Cargo.toml
[INFO] started frobbing nixcfg-0.2.0
[INFO] finished frobbing nixcfg-0.2.0
[INFO] frobbed toml for nixcfg-0.2.0 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/nixcfg/0.2.0/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing nixcfg-0.2.0 against beta-2019-08-13 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-0/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/nixcfg/0.2.0:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+beta-2019-08-13" "build" "--frozen"`
[INFO] [stdout] f8e5c811f0a580b299f5e001c1cf246f5228ae50eb9887e71b2d585ecafc414d
[INFO] running `"docker" "start" "-a" "f8e5c811f0a580b299f5e001c1cf246f5228ae50eb9887e71b2d585ecafc414d"`
[INFO] [stderr]    Compiling arenatree v0.1.3
[INFO] [stderr]    Compiling smol_str v0.1.12
[INFO] [stderr]    Compiling structopt v0.2.18
[INFO] [stderr]    Compiling rnix v0.4.2
[INFO] [stderr]    Compiling nixcfg v0.2.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:95:9
[INFO] [stderr]    |
[INFO] [stderr] 95 |         write!(file, "{}", content);
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/main.rs:126:13
[INFO] [stderr]     |
[INFO] [stderr] 126 |             write!(content, "{}", ast);
[INFO] [stderr]     |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]     = note: this warning originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 4.90s
[INFO] running `"docker" "inspect" "f8e5c811f0a580b299f5e001c1cf246f5228ae50eb9887e71b2d585ecafc414d"`
[INFO] running `"docker" "rm" "-f" "f8e5c811f0a580b299f5e001c1cf246f5228ae50eb9887e71b2d585ecafc414d"`
[INFO] [stdout] f8e5c811f0a580b299f5e001c1cf246f5228ae50eb9887e71b2d585ecafc414d
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-0/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/nixcfg/0.2.0:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+beta-2019-08-13" "test" "--frozen" "--no-run"`
[INFO] [stdout] 11ae18aa2a4377f96aa7e3d94a7e5aba6c68df2dfc100adc1589c98d53132662
[INFO] running `"docker" "start" "-a" "11ae18aa2a4377f96aa7e3d94a7e5aba6c68df2dfc100adc1589c98d53132662"`
[INFO] [stderr]    Compiling nixcfg v0.2.0 (/opt/crater/workdir)
[INFO] [stderr] error[E0308]: mismatched types
[INFO] [stderr]    --> src/main.rs:344:28
[INFO] [stderr]     |
[INFO] [stderr] 344 |                     value: replace_by
[INFO] [stderr]     |                            ^^^^^^^^^^
[INFO] [stderr]     |                            |
[INFO] [stderr]     |                            expected enum `std::option::Option`, found struct `std::string::String`
[INFO] [stderr]     |                            help: try using a variant of the expected type: `Some(replace_by)`
[INFO] [stderr]     |
[INFO] [stderr]     = note: expected type `std::option::Option<std::string::String>`
[INFO] [stderr]                found type `std::string::String`
[INFO] [stderr] 
[INFO] [stderr] error[E0063]: missing field `keep_eol` in initializer of `Command`
[INFO] [stderr]    --> src/main.rs:342:27
[INFO] [stderr]     |
[INFO] [stderr] 342 |                 let cmd = Command::Set {
[INFO] [stderr]     |                           ^^^^^^^^^^^^ missing `keep_eol`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0063, E0308.
[INFO] [stderr] For more information about an error, try `rustc --explain E0063`.
[INFO] [stderr] error: Could not compile `nixcfg`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "11ae18aa2a4377f96aa7e3d94a7e5aba6c68df2dfc100adc1589c98d53132662"`
[INFO] running `"docker" "rm" "-f" "11ae18aa2a4377f96aa7e3d94a7e5aba6c68df2dfc100adc1589c98d53132662"`
[INFO] [stdout] 11ae18aa2a4377f96aa7e3d94a7e5aba6c68df2dfc100adc1589c98d53132662