[INFO] crate hindley-milner 0.1.0 is already in cache
[INFO] extracting crate hindley-milner 0.1.0 into work/ex/beta-1.38-1/sources/1.37.0/reg/hindley-milner/0.1.0
[INFO] extracting crate hindley-milner 0.1.0 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/hindley-milner/0.1.0
[INFO] validating manifest of hindley-milner-0.1.0 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 hindley-milner-0.1.0 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 hindley-milner-0.1.0
[INFO] finished frobbing hindley-milner-0.1.0
[INFO] frobbed toml for hindley-milner-0.1.0 written to work/ex/beta-1.38-1/sources/1.37.0/reg/hindley-milner/0.1.0/Cargo.toml
[INFO] started frobbing hindley-milner-0.1.0
[INFO] finished frobbing hindley-milner-0.1.0
[INFO] frobbed toml for hindley-milner-0.1.0 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/hindley-milner/0.1.0/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 hindley-milner-0.1.0 against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/hindley-milner/0.1.0:/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" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] c31abc39581b657dfc414d15bb5e45b3c78da4d6e70d5594074f5d5fddaab5c5
[INFO] running `"docker" "start" "-a" "c31abc39581b657dfc414d15bb5e45b3c78da4d6e70d5594074f5d5fddaab5c5"`
[INFO] [stderr]    Compiling hindley-milner v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: struct is never constructed: `Namer`
[INFO] [stderr]   --> src/lib.rs:77:1
[INFO] [stderr]    |
[INFO] [stderr] 77 | struct Namer {
[INFO] [stderr]    | ^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `next`
[INFO] [stderr]   --> src/lib.rs:83:5
[INFO] [stderr]    |
[INFO] [stderr] 83 |     fn next(&mut self) -> String {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `name`
[INFO] [stderr]   --> src/lib.rs:89:5
[INFO] [stderr]    |
[INFO] [stderr] 89 |     fn name(&mut self, t: ArenaType) -> String {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `id`
[INFO] [stderr]    --> src/lib.rs:124:5
[INFO] [stderr]     |
[INFO] [stderr] 124 |     fn id(&self) -> usize {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `as_string`
[INFO] [stderr]    --> src/lib.rs:146:5
[INFO] [stderr]     |
[INFO] [stderr] 146 |     fn as_string(&self, a: &Vec<Type>, namer: &mut Namer) -> String {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `test_env`
[INFO] [stderr]    --> src/lib.rs:537:1
[INFO] [stderr]     |
[INFO] [stderr] 537 | fn test_env() -> (Vec<Type>, Env) {
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.72s
[INFO] running `"docker" "inspect" "c31abc39581b657dfc414d15bb5e45b3c78da4d6e70d5594074f5d5fddaab5c5"`
[INFO] running `"docker" "rm" "-f" "c31abc39581b657dfc414d15bb5e45b3c78da4d6e70d5594074f5d5fddaab5c5"`
[INFO] [stdout] c31abc39581b657dfc414d15bb5e45b3c78da4d6e70d5594074f5d5fddaab5c5
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/hindley-milner/0.1.0:/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" "+1.37.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] d2a6407e4c99cb99e69e74899994516af45f84583f7df41fd73331422248cf27
[INFO] running `"docker" "start" "-a" "d2a6407e4c99cb99e69e74899994516af45f84583f7df41fd73331422248cf27"`
[INFO] [stderr]    Compiling hindley-milner v0.1.0 (/opt/crater/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.01s
[INFO] running `"docker" "inspect" "d2a6407e4c99cb99e69e74899994516af45f84583f7df41fd73331422248cf27"`
[INFO] running `"docker" "rm" "-f" "d2a6407e4c99cb99e69e74899994516af45f84583f7df41fd73331422248cf27"`
[INFO] [stdout] d2a6407e4c99cb99e69e74899994516af45f84583f7df41fd73331422248cf27
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/hindley-milner/0.1.0:/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" "+1.37.0" "test" "--frozen"`
[INFO] [stdout] e134f56f63e8cf2423c4e8b3d1957ede46dbe60944319d2cdc5d7ef59d8524c7
[INFO] running `"docker" "start" "-a" "e134f56f63e8cf2423c4e8b3d1957ede46dbe60944319d2cdc5d7ef59d8524c7"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/hindley_milner-7c67534fe38aaf9d
[INFO] [stdout] 
[INFO] [stdout] running 9 tests
[INFO] [stdout] test test_int ... ok
[INFO] [stdout] test test_composition ... ok
[INFO] [stdout] test test_fun ... ok
[INFO] [stdout] test test_factorial ... ok
[INFO] [stdout] test test_generic_nongeneric ... ok
[INFO] [stdout] test test_mul ... ok
[INFO] [stdout] test test_mismatch ... ok
[INFO] [stdout] test test_recursive ... ok
[INFO] [stdout] test test_pair ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 9 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "e134f56f63e8cf2423c4e8b3d1957ede46dbe60944319d2cdc5d7ef59d8524c7"`
[INFO] running `"docker" "rm" "-f" "e134f56f63e8cf2423c4e8b3d1957ede46dbe60944319d2cdc5d7ef59d8524c7"`
[INFO] [stdout] e134f56f63e8cf2423c4e8b3d1957ede46dbe60944319d2cdc5d7ef59d8524c7