[INFO] crate recoreco 0.1.9 is already in cache
[INFO] extracting crate recoreco 0.1.9 into work/ex/beta-1.37-6/sources/1.36.0/reg/recoreco/0.1.9
[INFO] extracting crate recoreco 0.1.9 into work/ex/beta-1.37-6/sources/beta-2019-07-23/reg/recoreco/0.1.9
[INFO] validating manifest of recoreco-0.1.9 on toolchain 1.36.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of recoreco-0.1.9 on toolchain beta-2019-07-23
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing recoreco-0.1.9
[INFO] finished frobbing recoreco-0.1.9
[INFO] frobbed toml for recoreco-0.1.9 written to work/ex/beta-1.37-6/sources/1.36.0/reg/recoreco/0.1.9/Cargo.toml
[INFO] started frobbing recoreco-0.1.9
[INFO] finished frobbing recoreco-0.1.9
[INFO] frobbed toml for recoreco-0.1.9 written to work/ex/beta-1.37-6/sources/beta-2019-07-23/reg/recoreco/0.1.9/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache lock
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] testing recoreco-0.1.9 against 1.36.0 for beta-1.37-6
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-6/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/reg/recoreco/0.1.9:/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" "+1.36.0" "build" "--frozen"`
[INFO] [stdout] a1356221807d19b5619e7c1aa6294d98c67b5ff872e1c3161553091a1e302ea8
[INFO] running `"docker" "start" "-a" "a1356221807d19b5619e7c1aa6294d98c67b5ff872e1c3161553091a1e302ea8"`
[INFO] [stderr]    Compiling recoreco v0.1.9 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:184:17
[INFO] [stderr]     |
[INFO] [stderr] 184 |             let mut user_history = &mut samples_of_a[user_idx];
[INFO] [stderr]     |                 ----^^^^^^^^^^^^
[INFO] [stderr]     |                 |
[INFO] [stderr]     |                 help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.81s
[INFO] running `"docker" "inspect" "a1356221807d19b5619e7c1aa6294d98c67b5ff872e1c3161553091a1e302ea8"`
[INFO] running `"docker" "rm" "-f" "a1356221807d19b5619e7c1aa6294d98c67b5ff872e1c3161553091a1e302ea8"`
[INFO] [stdout] a1356221807d19b5619e7c1aa6294d98c67b5ff872e1c3161553091a1e302ea8
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-6/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/reg/recoreco/0.1.9:/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" "+1.36.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] 4bd5f5c6f3b6dcff357479dd9c2625b57706398e90e7ba8fc03a1d45523eacd3
[INFO] running `"docker" "start" "-a" "4bd5f5c6f3b6dcff357479dd9c2625b57706398e90e7ba8fc03a1d45523eacd3"`
[INFO] [stderr]    Compiling recoreco v0.1.9 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:184:17
[INFO] [stderr]     |
[INFO] [stderr] 184 |             let mut user_history = &mut samples_of_a[user_idx];
[INFO] [stderr]     |                 ----^^^^^^^^^^^^
[INFO] [stderr]     |                 |
[INFO] [stderr]     |                 help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 4.97s
[INFO] running `"docker" "inspect" "4bd5f5c6f3b6dcff357479dd9c2625b57706398e90e7ba8fc03a1d45523eacd3"`
[INFO] running `"docker" "rm" "-f" "4bd5f5c6f3b6dcff357479dd9c2625b57706398e90e7ba8fc03a1d45523eacd3"`
[INFO] [stdout] 4bd5f5c6f3b6dcff357479dd9c2625b57706398e90e7ba8fc03a1d45523eacd3
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-6/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/reg/recoreco/0.1.9:/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" "+1.36.0" "test" "--frozen"`
[INFO] [stdout] 1abb833547608027884bea4df3c0915d9ebd5e7cd5d39eadacaadfb0a9b0b593
[INFO] running `"docker" "start" "-a" "1abb833547608027884bea4df3c0915d9ebd5e7cd5d39eadacaadfb0a9b0b593"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.10s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/recoreco-34224757457b8e1a
[INFO] [stdout] 
[INFO] [stdout] running 7 tests
[INFO] [stdout] test llr::tests::scored_item_ordering_reversed ... ok
[INFO] [stdout] test stats::tests::dict_from_owned_tuple_iterator ... ok
[INFO] [stdout] test llr::tests::topk ... ok
[INFO] [stdout] test stats::tests::dict_from_tuple_iterator ... ok
[INFO] [stdout] test stats::tests::renaming_from_dict ... ok
[INFO] [stdout] test llr::tests::llr ... ok
[INFO] [stdout] test usage_tests::tests::programmatic_usage ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 7 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/crater/target/debug/deps/recoreco-0d63dd1985458872
[INFO] [stdout] running 0 tests
[INFO] [stderr]    Doc-tests recoreco
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test src/lib.rs - indicators (line 72) ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "1abb833547608027884bea4df3c0915d9ebd5e7cd5d39eadacaadfb0a9b0b593"`
[INFO] running `"docker" "rm" "-f" "1abb833547608027884bea4df3c0915d9ebd5e7cd5d39eadacaadfb0a9b0b593"`
[INFO] [stdout] 1abb833547608027884bea4df3c0915d9ebd5e7cd5d39eadacaadfb0a9b0b593