[INFO] fetching crate incremental-writer 0.1.2...
[INFO] testing incremental-writer-0.1.2 against master#1f7f8ea0721a3b1eb73e6c6d25cccb371434b320 for pr-154065-1
[INFO] extracting crate incremental-writer 0.1.2 into /workspace/builds/worker-4-tc1/source
[INFO] started tweaking crates.io crate incremental-writer 0.1.2
[INFO] finished tweaking crates.io crate incremental-writer 0.1.2
[INFO] tweaked toml for crates.io crate incremental-writer 0.1.2 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate incremental-writer 0.1.2 on toolchain 1f7f8ea0721a3b1eb73e6c6d25cccb371434b320
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1f7f8ea0721a3b1eb73e6c6d25cccb371434b320" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate incremental-writer 0.1.2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1f7f8ea0721a3b1eb73e6c6d25cccb371434b320" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1f7f8ea0721a3b1eb73e6c6d25cccb371434b320" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 903086016d1ae55d0ded4d70e88a7ab1c10c93af1ba734fa699b6180fcfcf329
[INFO] running `Command { std: "docker" "start" "-a" "903086016d1ae55d0ded4d70e88a7ab1c10c93af1ba734fa699b6180fcfcf329", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "903086016d1ae55d0ded4d70e88a7ab1c10c93af1ba734fa699b6180fcfcf329", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "903086016d1ae55d0ded4d70e88a7ab1c10c93af1ba734fa699b6180fcfcf329", kill_on_drop: false }`
[INFO] [stdout] 903086016d1ae55d0ded4d70e88a7ab1c10c93af1ba734fa699b6180fcfcf329
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1f7f8ea0721a3b1eb73e6c6d25cccb371434b320" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 982358fcd3e20f0040e8be1681cd32914a029bf06f6e453a577704330ba68cf9
[INFO] running `Command { std: "docker" "start" "-a" "982358fcd3e20f0040e8be1681cd32914a029bf06f6e453a577704330ba68cf9", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.19
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling syn v1.0.38
[INFO] [stderr]    Compiling serde_derive v1.0.115
[INFO] [stderr]    Compiling serde v1.0.115
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling serde_json v1.0.57
[INFO] [stderr]    Compiling itoa v0.4.6
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]    Compiling incremental-writer v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct `Record` is never constructed
[INFO] [stdout]    --> src/json/mod.rs:104:8
[INFO] [stdout]     |
[INFO] [stdout] 104 | struct Record { 
[INFO] [stdout]     |        ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 13.56s
[INFO] running `Command { std: "docker" "inspect" "982358fcd3e20f0040e8be1681cd32914a029bf06f6e453a577704330ba68cf9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "982358fcd3e20f0040e8be1681cd32914a029bf06f6e453a577704330ba68cf9", kill_on_drop: false }`
[INFO] [stdout] 982358fcd3e20f0040e8be1681cd32914a029bf06f6e453a577704330ba68cf9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1f7f8ea0721a3b1eb73e6c6d25cccb371434b320" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 977886e109dcf0db1d77a435360844da1d5616c2f5778190b9a34b833b3b3609
[INFO] running `Command { std: "docker" "start" "-a" "977886e109dcf0db1d77a435360844da1d5616c2f5778190b9a34b833b3b3609", kill_on_drop: false }`
[INFO] [stdout] warning: struct `Record` is never constructed
[INFO] [stdout]    --> src/json/mod.rs:104:8
[INFO] [stdout]     |
[INFO] [stdout] 104 | struct Record { 
[INFO] [stdout]     |        ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling incremental-writer v0.1.2 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.54s
[INFO] running `Command { std: "docker" "inspect" "977886e109dcf0db1d77a435360844da1d5616c2f5778190b9a34b833b3b3609", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "977886e109dcf0db1d77a435360844da1d5616c2f5778190b9a34b833b3b3609", kill_on_drop: false }`
[INFO] [stdout] 977886e109dcf0db1d77a435360844da1d5616c2f5778190b9a34b833b3b3609
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1f7f8ea0721a3b1eb73e6c6d25cccb371434b320" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 007b1d73f8fd63fed769231ba427927fa9d875429fd9b54b45d4ad22a2e09557
[INFO] running `Command { std: "docker" "start" "-a" "007b1d73f8fd63fed769231ba427927fa9d875429fd9b54b45d4ad22a2e09557", kill_on_drop: false }`
[INFO] [stderr] warning: struct `Record` is never constructed
[INFO] [stderr]    --> src/json/mod.rs:104:8
[INFO] [stderr]     |
[INFO] [stderr] 104 | struct Record { 
[INFO] [stderr]     |        ^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `incremental-writer` (lib) generated 1 warning
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.06s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/incremental_writer-549b62d5ac58fbbc)
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test json::writer_writes_square_brackets_to_buffer ... FAILED
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout] 
[INFO] [stdout] ---- json::writer_writes_square_brackets_to_buffer stdout ----
[INFO] [stdout] 
[INFO] [stdout] thread 'json::writer_writes_square_brackets_to_buffer' (16) panicked at src/json/mod.rs:81:46:
[INFO] [stdout] called `Result::unwrap()` on an `Err` value: Os { code: 30, kind: ReadOnlyFilesystem, message: "Read-only file system" }
[INFO] [stdout] stack backtrace:
[INFO] [stdout]    0:     0x623d8f414a6a - std[f92b4c606f291077]::backtrace_rs::backtrace::libunwind::trace
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/../../backtrace/src/backtrace/libunwind.rs:117:9
[INFO] [stdout]    1:     0x623d8f414a6a - std[f92b4c606f291077]::backtrace_rs::backtrace::trace_unsynchronized::<std[f92b4c606f291077]::sys::backtrace::_print_fmt::{closure#1}>
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/../../backtrace/src/backtrace/mod.rs:66:14
[INFO] [stdout]    2:     0x623d8f414a6a - std[f92b4c606f291077]::sys::backtrace::_print_fmt
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/sys/backtrace.rs:74:9
[INFO] [stdout]    3:     0x623d8f414a6a - <<std[f92b4c606f291077]::sys::backtrace::BacktraceLock>::print::DisplayBacktrace as core[786f478f706679df]::fmt::Display>::fmt
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/sys/backtrace.rs:44:26
[INFO] [stdout]    4:     0x623d8f4287da - <core[786f478f706679df]::fmt::rt::Argument>::fmt
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/core/src/fmt/rt.rs:152:76
[INFO] [stdout]    5:     0x623d8f4287da - core[786f478f706679df]::fmt::write
[INFO] [stdout]    6:     0x623d8f4193c2 - std[f92b4c606f291077]::io::default_write_fmt::<alloc[64763625b5a07cdb]::vec::Vec<u8>>
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/io/mod.rs:639:11
[INFO] [stdout]    7:     0x623d8f4193c2 - <alloc[64763625b5a07cdb]::vec::Vec<u8> as std[f92b4c606f291077]::io::Write>::write_fmt
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/io/mod.rs:1994:13
[INFO] [stdout]    8:     0x623d8f3f3c4f - <std[f92b4c606f291077]::sys::backtrace::BacktraceLock>::print
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/sys/backtrace.rs:47:9
[INFO] [stdout]    9:     0x623d8f3f3c4f - std[f92b4c606f291077]::panicking::default_hook::{closure#0}
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/panicking.rs:292:27
[INFO] [stdout]   10:     0x623d8f40cfe9 - std[f92b4c606f291077]::panicking::default_hook
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/panicking.rs:316:9
[INFO] [stdout]   11:     0x623d8f3aa06c - <alloc[64763625b5a07cdb]::boxed::Box<dyn for<'a, 'b> core[786f478f706679df]::ops::function::Fn<(&'a std[f92b4c606f291077]::panic::PanicHookInfo<'b>,), Output = ()> + core[786f478f706679df]::marker::Sync + core[786f478f706679df]::marker::Send> as core[786f478f706679df]::ops::function::Fn<(&std[f92b4c606f291077]::panic::PanicHookInfo,)>>::call
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/alloc/src/boxed.rs:2254:9
[INFO] [stdout]   12:     0x623d8f3aa06c - test[20e1f0ae6cad7a17]::test_main_with_exit_callback::<test[20e1f0ae6cad7a17]::test_main::{closure#0}>::{closure#0}
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/test/src/lib.rs:145:21
[INFO] [stdout]   13:     0x623d8f40d1a2 - <alloc[64763625b5a07cdb]::boxed::Box<dyn for<'a, 'b> core[786f478f706679df]::ops::function::Fn<(&'a std[f92b4c606f291077]::panic::PanicHookInfo<'b>,), Output = ()> + core[786f478f706679df]::marker::Sync + core[786f478f706679df]::marker::Send> as core[786f478f706679df]::ops::function::Fn<(&std[f92b4c606f291077]::panic::PanicHookInfo,)>>::call
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/alloc/src/boxed.rs:2254:9
[INFO] [stdout]   14:     0x623d8f40d1a2 - std[f92b4c606f291077]::panicking::panic_with_hook
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/panicking.rs:833:13
[INFO] [stdout]   15:     0x623d8f3f3d08 - std[f92b4c606f291077]::panicking::panic_handler::{closure#0}
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/panicking.rs:698:13
[INFO] [stdout]   16:     0x623d8f3eb6a9 - std[f92b4c606f291077]::sys::backtrace::__rust_end_short_backtrace::<std[f92b4c606f291077]::panicking::panic_handler::{closure#0}, !>
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/sys/backtrace.rs:182:18
[INFO] [stdout]   17:     0x623d8f3f4a1d - __rustc[8241495c18a89d70]::rust_begin_unwind
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/panicking.rs:689:5
[INFO] [stdout]   18:     0x623d8f428f2c - core[786f478f706679df]::panicking::panic_fmt
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/core/src/panicking.rs:80:14
[INFO] [stdout]   19:     0x623d8f428ca2 - core[786f478f706679df]::result::unwrap_failed
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/core/src/result.rs:1867:5
[INFO] [stdout]   20:     0x623d8f3967a4 - <core[786f478f706679df]::result::Result<std[f92b4c606f291077]::fs::File, std[f92b4c606f291077]::io::error::Error>>::unwrap
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/core/src/result.rs:1233:23
[INFO] [stdout]   21:     0x623d8f3967a4 - incremental_writer[b053353e016d93d3]::json::writer_writes_square_brackets_to_buffer
[INFO] [stdout]                                at /opt/rustwide/workdir/src/json/mod.rs:81:46
[INFO] [stdout]   22:     0x623d8f3959b7 - incremental_writer[b053353e016d93d3]::json::writer_writes_square_brackets_to_buffer::{closure#0}
[INFO] [stdout]                                at /opt/rustwide/workdir/src/json/mod.rs:64:45
[INFO] [stdout]   23:     0x623d8f39a066 - <incremental_writer[b053353e016d93d3]::json::writer_writes_square_brackets_to_buffer::{closure#0} as core[786f478f706679df]::ops::function::FnOnce<()>>::call_once
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   24:     0x623d8f39e14b - <fn() -> core[786f478f706679df]::result::Result<(), alloc[64763625b5a07cdb]::string::String> as core[786f478f706679df]::ops::function::FnOnce<()>>::call_once
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   25:     0x623d8f39e14b - test[20e1f0ae6cad7a17]::__rust_begin_short_backtrace::<core[786f478f706679df]::result::Result<(), alloc[64763625b5a07cdb]::string::String>, fn() -> core[786f478f706679df]::result::Result<(), alloc[64763625b5a07cdb]::string::String>>
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/test/src/lib.rs:663:18
[INFO] [stdout]   26:     0x623d8f3aab3b - test[20e1f0ae6cad7a17]::run_test_in_process::{closure#0}
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/test/src/lib.rs:686:74
[INFO] [stdout]   27:     0x623d8f3aab3b - <core[786f478f706679df]::panic::unwind_safe::AssertUnwindSafe<test[20e1f0ae6cad7a17]::run_test_in_process::{closure#0}> as core[786f478f706679df]::ops::function::FnOnce<()>>::call_once
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/core/src/panic/unwind_safe.rs:275:9
[INFO] [stdout]   28:     0x623d8f3aab3b - std[f92b4c606f291077]::panicking::catch_unwind::do_call::<core[786f478f706679df]::panic::unwind_safe::AssertUnwindSafe<test[20e1f0ae6cad7a17]::run_test_in_process::{closure#0}>, core[786f478f706679df]::result::Result<(), alloc[64763625b5a07cdb]::string::String>>
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/panicking.rs:581:40
[INFO] [stdout]   29:     0x623d8f3aab3b - std[f92b4c606f291077]::panicking::catch_unwind::<core[786f478f706679df]::result::Result<(), alloc[64763625b5a07cdb]::string::String>, core[786f478f706679df]::panic::unwind_safe::AssertUnwindSafe<test[20e1f0ae6cad7a17]::run_test_in_process::{closure#0}>>
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/panicking.rs:544:19
[INFO] [stdout]   30:     0x623d8f3aab3b - std[f92b4c606f291077]::panic::catch_unwind::<core[786f478f706679df]::panic::unwind_safe::AssertUnwindSafe<test[20e1f0ae6cad7a17]::run_test_in_process::{closure#0}>, core[786f478f706679df]::result::Result<(), alloc[64763625b5a07cdb]::string::String>>
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/panic.rs:359:14
[INFO] [stdout]   31:     0x623d8f3aab3b - test[20e1f0ae6cad7a17]::run_test_in_process
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/test/src/lib.rs:686:27
[INFO] [stdout]   32:     0x623d8f3aab3b - test[20e1f0ae6cad7a17]::run_test::{closure#0}
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/test/src/lib.rs:607:43
[INFO] [stdout]   33:     0x623d8f3a6254 - test[20e1f0ae6cad7a17]::run_test::{closure#1}
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/test/src/lib.rs:637:41
[INFO] [stdout]   34:     0x623d8f3a6254 - std[f92b4c606f291077]::sys::backtrace::__rust_begin_short_backtrace::<test[20e1f0ae6cad7a17]::run_test::{closure#1}, ()>
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/sys/backtrace.rs:166:18
[INFO] [stdout]   35:     0x623d8f3ad742 - std[f92b4c606f291077]::thread::lifecycle::spawn_unchecked::<test[20e1f0ae6cad7a17]::run_test::{closure#1}, ()>::{closure#1}::{closure#0}
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/thread/lifecycle.rs:91:13
[INFO] [stdout]   36:     0x623d8f3ad742 - <core[786f478f706679df]::panic::unwind_safe::AssertUnwindSafe<std[f92b4c606f291077]::thread::lifecycle::spawn_unchecked<test[20e1f0ae6cad7a17]::run_test::{closure#1}, ()>::{closure#1}::{closure#0}> as core[786f478f706679df]::ops::function::FnOnce<()>>::call_once
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/core/src/panic/unwind_safe.rs:275:9
[INFO] [stdout]   37:     0x623d8f3ad742 - std[f92b4c606f291077]::panicking::catch_unwind::do_call::<core[786f478f706679df]::panic::unwind_safe::AssertUnwindSafe<std[f92b4c606f291077]::thread::lifecycle::spawn_unchecked<test[20e1f0ae6cad7a17]::run_test::{closure#1}, ()>::{closure#1}::{closure#0}>, ()>
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/panicking.rs:581:40
[INFO] [stdout]   38:     0x623d8f3ad742 - std[f92b4c606f291077]::panicking::catch_unwind::<(), core[786f478f706679df]::panic::unwind_safe::AssertUnwindSafe<std[f92b4c606f291077]::thread::lifecycle::spawn_unchecked<test[20e1f0ae6cad7a17]::run_test::{closure#1}, ()>::{closure#1}::{closure#0}>>
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/panicking.rs:544:19
[INFO] [stdout]   39:     0x623d8f3ad742 - std[f92b4c606f291077]::panic::catch_unwind::<core[786f478f706679df]::panic::unwind_safe::AssertUnwindSafe<std[f92b4c606f291077]::thread::lifecycle::spawn_unchecked<test[20e1f0ae6cad7a17]::run_test::{closure#1}, ()>::{closure#1}::{closure#0}>, ()>
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/panic.rs:359:14
[INFO] [stdout]   40:     0x623d8f3ad742 - std[f92b4c606f291077]::thread::lifecycle::spawn_unchecked::<test[20e1f0ae6cad7a17]::run_test::{closure#1}, ()>::{closure#1}
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/thread/lifecycle.rs:89:26
[INFO] [stdout]   41:     0x623d8f3ad742 - <std[f92b4c606f291077]::thread::lifecycle::spawn_unchecked<test[20e1f0ae6cad7a17]::run_test::{closure#1}, ()>::{closure#1} as core[786f478f706679df]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   42:     0x623d8f41433f - <alloc[64763625b5a07cdb]::boxed::Box<dyn core[786f478f706679df]::ops::function::FnOnce<(), Output = ()> + core[786f478f706679df]::marker::Send> as core[786f478f706679df]::ops::function::FnOnce<()>>::call_once
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/alloc/src/boxed.rs:2240:9
[INFO] [stdout]   43:     0x623d8f41433f - <std[f92b4c606f291077]::sys::thread::unix::Thread>::new::thread_start
[INFO] [stdout]                                at /rustc/1f7f8ea0721a3b1eb73e6c6d25cccb371434b320/library/std/src/sys/thread/unix.rs:118:17
[INFO] [stdout]   44:     0x7e6adad99aa4 - <unknown>
[INFO] [stdout]   45:     0x7e6adae26a64 - clone
[INFO] [stdout]   46:                0x0 - <unknown>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout]     json::writer_writes_square_brackets_to_buffer
[INFO] [stdout] 
[INFO] [stdout] test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.06s
[INFO] [stdout] 
[INFO] [stderr] error: test failed, to rerun pass `--lib`
[INFO] running `Command { std: "docker" "inspect" "007b1d73f8fd63fed769231ba427927fa9d875429fd9b54b45d4ad22a2e09557", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "007b1d73f8fd63fed769231ba427927fa9d875429fd9b54b45d4ad22a2e09557", kill_on_drop: false }`
[INFO] [stdout] 007b1d73f8fd63fed769231ba427927fa9d875429fd9b54b45d4ad22a2e09557
