[INFO] fetching crate basic_xlsx_writer 0.1.3...
[INFO] testing basic_xlsx_writer-0.1.3 against beta-2022-04-10 for beta-1.61-1
[INFO] extracting crate basic_xlsx_writer 0.1.3 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate basic_xlsx_writer 0.1.3 on toolchain beta-2022-04-10
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-04-10" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate basic_xlsx_writer 0.1.3
[INFO] finished tweaking crates.io crate basic_xlsx_writer 0.1.3
[INFO] tweaked toml for crates.io crate basic_xlsx_writer 0.1.3 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-04-10" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-04-10" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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:eaef2f80f755933c374d2ae5edccceec0c1312ceb8a4e0b6404e8ab76561e1e5" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 6b4ac42db0ced19806bd3e0083773cb45508a3b304c8c1f52b9d632eca539a76
[INFO] running `Command { std: "docker" "start" "-a" "6b4ac42db0ced19806bd3e0083773cb45508a3b304c8c1f52b9d632eca539a76", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6b4ac42db0ced19806bd3e0083773cb45508a3b304c8c1f52b9d632eca539a76", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6b4ac42db0ced19806bd3e0083773cb45508a3b304c8c1f52b9d632eca539a76", kill_on_drop: false }`
[INFO] [stdout] 6b4ac42db0ced19806bd3e0083773cb45508a3b304c8c1f52b9d632eca539a76
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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=warn" "-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:eaef2f80f755933c374d2ae5edccceec0c1312ceb8a4e0b6404e8ab76561e1e5" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 34c168167315b1e7b4e394c19d34d3e004a3e8df5925a4ce5e3e0c1485bcc809
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "34c168167315b1e7b4e394c19d34d3e004a3e8df5925a4ce5e3e0c1485bcc809", kill_on_drop: false }`
[INFO] [stderr]    Compiling pkg-config v0.3.25
[INFO] [stderr]    Compiling crc32fast v1.3.2
[INFO] [stderr]    Compiling podio v0.1.7
[INFO] [stderr]    Compiling miniz_oxide v0.5.1
[INFO] [stderr]    Compiling time v0.1.44
[INFO] [stderr]    Compiling msdos_time v0.1.6
[INFO] [stderr]    Compiling bzip2-sys v0.1.11+1.0.8
[INFO] [stderr]    Compiling flate2 v1.0.23
[INFO] [stderr]    Compiling bzip2 v0.3.3
[INFO] [stderr]    Compiling zip v0.4.2
[INFO] [stderr]    Compiling basic_xlsx_writer v0.1.3 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:174:61
[INFO] [stdout]     |
[INFO] [stdout] 174 | fn write_value(cv: &CellValue, ref_id: String, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                                             ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 174 - fn write_value(cv: &CellValue, ref_id: String, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 174 + fn write_value(cv: &CellValue, ref_id: String, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:143:38
[INFO] [stdout]     |
[INFO] [stdout] 143 |     pub fn write(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                      ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 143 -     pub fn write(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 143 +     pub fn write(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:217:52
[INFO] [stdout]     |
[INFO] [stdout] 217 |     fn write(&self, row_index: usize, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                                    ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 217 -     fn write(&self, row_index: usize, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 217 +     fn write(&self, row_index: usize, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:270:39
[INFO] [stdout]     |
[INFO] [stdout] 270 |     fn write_head(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                       ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 270 -     fn write_head(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 270 +     fn write_head(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:300:45
[INFO] [stdout]     |
[INFO] [stdout] 300 |     fn write_data_begin(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                             ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 300 -     fn write_data_begin(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 300 +     fn write_data_begin(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:304:43
[INFO] [stdout]     |
[INFO] [stdout] 304 |     fn write_data_end(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                           ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 304 -     fn write_data_end(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 304 +     fn write_data_end(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:308:34
[INFO] [stdout]     |
[INFO] [stdout] 308 |     fn close(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                  ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 308 -     fn close(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 308 +     fn close(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:146:42
[INFO] [stdout]     |
[INFO] [stdout] 146 |     fn create_content_types(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                          ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 146 -     fn create_content_types(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 146 +     fn create_content_types(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:168:33
[INFO] [stdout]     |
[INFO] [stdout] 168 |     fn create_rels(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                 ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 168 -     fn create_rels(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 168 +     fn create_rels(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:179:32
[INFO] [stdout]     |
[INFO] [stdout] 179 |     fn create_app(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 179 -     fn create_app(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 179 +     fn create_app(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:204:33
[INFO] [stdout]     |
[INFO] [stdout] 204 |     fn create_core(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                 ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 204 -     fn create_core(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 204 +     fn create_core(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:213:35
[INFO] [stdout]     |
[INFO] [stdout] 213 |     fn create_styles(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                   ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 213 -     fn create_styles(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 213 +     fn create_styles(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:260:48
[INFO] [stdout]     |
[INFO] [stdout] 260 |     fn create_workbook(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                                ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 260 -     fn create_workbook(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 260 +     fn create_workbook(&mut self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:282:47
[INFO] [stdout]     |
[INFO] [stdout] 282 |     fn create_xl_rels(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                               ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 282 -     fn create_xl_rels(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 282 +     fn create_xl_rels(&mut self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:303:37
[INFO] [stdout]     |
[INFO] [stdout] 303 |     fn create_xl_theme(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                     ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 303 -     fn create_xl_theme(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 303 +     fn create_xl_theme(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stdout]   --> src/workbook.rs:90:9
[INFO] [stdout]    |
[INFO] [stdout] 90 |         fs::create_dir(root.as_path()).is_ok();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 16 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 11.62s
[INFO] running `Command { std: "docker" "inspect" "34c168167315b1e7b4e394c19d34d3e004a3e8df5925a4ce5e3e0c1485bcc809", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "34c168167315b1e7b4e394c19d34d3e004a3e8df5925a4ce5e3e0c1485bcc809", kill_on_drop: false }`
[INFO] [stdout] 34c168167315b1e7b4e394c19d34d3e004a3e8df5925a4ce5e3e0c1485bcc809
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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=warn" "-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:eaef2f80f755933c374d2ae5edccceec0c1312ceb8a4e0b6404e8ab76561e1e5" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 31004ca8b8a83a9a51bf4a454e36b58bac723b7a6c74d856580c4a0569f80353
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "31004ca8b8a83a9a51bf4a454e36b58bac723b7a6c74d856580c4a0569f80353", kill_on_drop: false }`
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:174:61
[INFO] [stdout]     |
[INFO] [stdout] 174 | fn write_value(cv: &CellValue, ref_id: String, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                                             ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 174 - fn write_value(cv: &CellValue, ref_id: String, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 174 + fn write_value(cv: &CellValue, ref_id: String, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:143:38
[INFO] [stdout]     |
[INFO] [stdout] 143 |     pub fn write(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                      ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 143 -     pub fn write(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 143 +     pub fn write(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling basic_xlsx_writer v0.1.3 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:217:52
[INFO] [stdout]     |
[INFO] [stdout] 217 |     fn write(&self, row_index: usize, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                                    ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 217 -     fn write(&self, row_index: usize, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 217 +     fn write(&self, row_index: usize, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:270:39
[INFO] [stdout]     |
[INFO] [stdout] 270 |     fn write_head(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                       ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 270 -     fn write_head(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 270 +     fn write_head(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:300:45
[INFO] [stdout]     |
[INFO] [stdout] 300 |     fn write_data_begin(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                             ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 300 -     fn write_data_begin(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 300 +     fn write_data_begin(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:304:43
[INFO] [stdout]     |
[INFO] [stdout] 304 |     fn write_data_end(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                           ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 304 -     fn write_data_end(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 304 +     fn write_data_end(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:308:34
[INFO] [stdout]     |
[INFO] [stdout] 308 |     fn close(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                  ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 308 -     fn close(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 308 +     fn close(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:146:42
[INFO] [stdout]     |
[INFO] [stdout] 146 |     fn create_content_types(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                          ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 146 -     fn create_content_types(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 146 +     fn create_content_types(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:168:33
[INFO] [stdout]     |
[INFO] [stdout] 168 |     fn create_rels(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                 ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 168 -     fn create_rels(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 168 +     fn create_rels(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:179:32
[INFO] [stdout]     |
[INFO] [stdout] 179 |     fn create_app(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 179 -     fn create_app(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 179 +     fn create_app(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:204:33
[INFO] [stdout]     |
[INFO] [stdout] 204 |     fn create_core(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                 ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 204 -     fn create_core(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 204 +     fn create_core(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:213:35
[INFO] [stdout]     |
[INFO] [stdout] 213 |     fn create_styles(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                   ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 213 -     fn create_styles(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 213 +     fn create_styles(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:260:48
[INFO] [stdout]     |
[INFO] [stdout] 260 |     fn create_workbook(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                                ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 260 -     fn create_workbook(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 260 +     fn create_workbook(&mut self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:282:47
[INFO] [stdout]     |
[INFO] [stdout] 282 |     fn create_xl_rels(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                               ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 282 -     fn create_xl_rels(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 282 +     fn create_xl_rels(&mut self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:303:37
[INFO] [stdout]     |
[INFO] [stdout] 303 |     fn create_xl_theme(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                     ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 303 -     fn create_xl_theme(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 303 +     fn create_xl_theme(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stdout]   --> src/workbook.rs:90:9
[INFO] [stdout]    |
[INFO] [stdout] 90 |         fs::create_dir(root.as_path()).is_ok();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 16 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:174:61
[INFO] [stdout]     |
[INFO] [stdout] 174 | fn write_value(cv: &CellValue, ref_id: String, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                                             ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 174 - fn write_value(cv: &CellValue, ref_id: String, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 174 + fn write_value(cv: &CellValue, ref_id: String, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:143:38
[INFO] [stdout]     |
[INFO] [stdout] 143 |     pub fn write(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                      ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 143 -     pub fn write(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 143 +     pub fn write(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:217:52
[INFO] [stdout]     |
[INFO] [stdout] 217 |     fn write(&self, row_index: usize, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                                    ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 217 -     fn write(&self, row_index: usize, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 217 +     fn write(&self, row_index: usize, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:270:39
[INFO] [stdout]     |
[INFO] [stdout] 270 |     fn write_head(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                       ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 270 -     fn write_head(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 270 +     fn write_head(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:300:45
[INFO] [stdout]     |
[INFO] [stdout] 300 |     fn write_data_begin(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                             ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 300 -     fn write_data_begin(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 300 +     fn write_data_begin(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:304:43
[INFO] [stdout]     |
[INFO] [stdout] 304 |     fn write_data_end(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                           ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 304 -     fn write_data_end(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 304 +     fn write_data_end(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/sheet.rs:308:34
[INFO] [stdout]     |
[INFO] [stdout] 308 |     fn close(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                  ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 308 -     fn close(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 308 +     fn close(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:146:42
[INFO] [stdout]     |
[INFO] [stdout] 146 |     fn create_content_types(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                          ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 146 -     fn create_content_types(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 146 +     fn create_content_types(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:168:33
[INFO] [stdout]     |
[INFO] [stdout] 168 |     fn create_rels(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                 ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 168 -     fn create_rels(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 168 +     fn create_rels(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:179:32
[INFO] [stdout]     |
[INFO] [stdout] 179 |     fn create_app(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 179 -     fn create_app(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 179 +     fn create_app(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:204:33
[INFO] [stdout]     |
[INFO] [stdout] 204 |     fn create_core(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                 ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 204 -     fn create_core(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 204 +     fn create_core(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:213:35
[INFO] [stdout]     |
[INFO] [stdout] 213 |     fn create_styles(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                   ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 213 -     fn create_styles(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 213 +     fn create_styles(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:260:48
[INFO] [stdout]     |
[INFO] [stdout] 260 |     fn create_workbook(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                                ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 260 -     fn create_workbook(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 260 +     fn create_workbook(&mut self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:282:47
[INFO] [stdout]     |
[INFO] [stdout] 282 |     fn create_xl_rels(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                               ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 282 -     fn create_xl_rels(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stdout] 282 +     fn create_xl_rels(&mut self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/workbook.rs:303:37
[INFO] [stdout]     |
[INFO] [stdout] 303 |     fn create_xl_theme(writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                     ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 303 -     fn create_xl_theme(writer: &mut Write) -> Result<()> {
[INFO] [stdout] 303 +     fn create_xl_theme(writer: &mut dyn Write) -> Result<()> {
[INFO] [stdout]     | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stdout]   --> src/workbook.rs:90:9
[INFO] [stdout]    |
[INFO] [stdout] 90 |         fs::create_dir(root.as_path()).is_ok();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 16 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.93s
[INFO] [stderr]   Executable unittests src/lib.rs (/opt/rustwide/target/debug/deps/basic_xlsx_writer-86935d7e07712ff4)
[INFO] running `Command { std: "docker" "inspect" "31004ca8b8a83a9a51bf4a454e36b58bac723b7a6c74d856580c4a0569f80353", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "31004ca8b8a83a9a51bf4a454e36b58bac723b7a6c74d856580c4a0569f80353", kill_on_drop: false }`
[INFO] [stdout] 31004ca8b8a83a9a51bf4a454e36b58bac723b7a6c74d856580c4a0569f80353
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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=warn" "-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:eaef2f80f755933c374d2ae5edccceec0c1312ceb8a4e0b6404e8ab76561e1e5" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] e8100c838d3c38e65f470c4a5fa9495c5fc29c7fdc119041b622f557a7a0a56f
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "e8100c838d3c38e65f470c4a5fa9495c5fc29c7fdc119041b622f557a7a0a56f", kill_on_drop: false }`
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/sheet.rs:174:61
[INFO] [stderr]     |
[INFO] [stderr] 174 | fn write_value(cv: &CellValue, ref_id: String, writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                                             ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 174 - fn write_value(cv: &CellValue, ref_id: String, writer: &mut Write) -> Result<()> {
[INFO] [stderr] 174 + fn write_value(cv: &CellValue, ref_id: String, writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/sheet.rs:143:38
[INFO] [stderr]     |
[INFO] [stderr] 143 |     pub fn write(&self, writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                      ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 143 -     pub fn write(&self, writer: &mut Write) -> Result<()> {
[INFO] [stderr] 143 +     pub fn write(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/sheet.rs:217:52
[INFO] [stderr]     |
[INFO] [stderr] 217 |     fn write(&self, row_index: usize, writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                                    ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 217 -     fn write(&self, row_index: usize, writer: &mut Write) -> Result<()> {
[INFO] [stderr] 217 +     fn write(&self, row_index: usize, writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/sheet.rs:270:39
[INFO] [stderr]     |
[INFO] [stderr] 270 |     fn write_head(&self, writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                       ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 270 -     fn write_head(&self, writer: &mut Write) -> Result<()> {
[INFO] [stderr] 270 +     fn write_head(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/sheet.rs:300:45
[INFO] [stderr]     |
[INFO] [stderr] 300 |     fn write_data_begin(&self, writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                             ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 300 -     fn write_data_begin(&self, writer: &mut Write) -> Result<()> {
[INFO] [stderr] 300 +     fn write_data_begin(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/sheet.rs:304:43
[INFO] [stderr]     |
[INFO] [stderr] 304 |     fn write_data_end(&self, writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                           ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 304 -     fn write_data_end(&self, writer: &mut Write) -> Result<()> {
[INFO] [stderr] 304 +     fn write_data_end(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/sheet.rs:308:34
[INFO] [stderr]     |
[INFO] [stderr] 308 |     fn close(&self, writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                  ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 308 -     fn close(&self, writer: &mut Write) -> Result<()> {
[INFO] [stderr] 308 +     fn close(&self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/workbook.rs:146:42
[INFO] [stderr]     |
[INFO] [stderr] 146 |     fn create_content_types(writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                          ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 146 -     fn create_content_types(writer: &mut Write) -> Result<()> {
[INFO] [stderr] 146 +     fn create_content_types(writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/workbook.rs:168:33
[INFO] [stderr]     |
[INFO] [stderr] 168 |     fn create_rels(writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                 ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 168 -     fn create_rels(writer: &mut Write) -> Result<()> {
[INFO] [stderr] 168 +     fn create_rels(writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/workbook.rs:179:32
[INFO] [stderr]     |
[INFO] [stderr] 179 |     fn create_app(writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 179 -     fn create_app(writer: &mut Write) -> Result<()> {
[INFO] [stderr] 179 +     fn create_app(writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/workbook.rs:204:33
[INFO] [stderr]     |
[INFO] [stderr] 204 |     fn create_core(writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                 ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 204 -     fn create_core(writer: &mut Write) -> Result<()> {
[INFO] [stderr] 204 +     fn create_core(writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/workbook.rs:213:35
[INFO] [stderr]     |
[INFO] [stderr] 213 |     fn create_styles(writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                   ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 213 -     fn create_styles(writer: &mut Write) -> Result<()> {
[INFO] [stderr] 213 +     fn create_styles(writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/workbook.rs:260:48
[INFO] [stderr]     |
[INFO] [stderr] 260 |     fn create_workbook(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                                ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 260 -     fn create_workbook(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stderr] 260 +     fn create_workbook(&mut self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/workbook.rs:282:47
[INFO] [stderr]     |
[INFO] [stderr] 282 |     fn create_xl_rels(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                               ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 282 -     fn create_xl_rels(&mut self, writer: &mut Write) -> Result<()> {
[INFO] [stderr] 282 +     fn create_xl_rels(&mut self, writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]    --> src/workbook.rs:303:37
[INFO] [stderr]     |
[INFO] [stderr] 303 |     fn create_xl_theme(writer: &mut Write) -> Result<()> {
[INFO] [stderr]     |                                     ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]     |
[INFO] [stderr] 303 -     fn create_xl_theme(writer: &mut Write) -> Result<()> {
[INFO] [stderr] 303 +     fn create_xl_theme(writer: &mut dyn Write) -> Result<()> {
[INFO] [stderr]     | 
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]   --> src/workbook.rs:90:9
[INFO] [stderr]    |
[INFO] [stderr] 90 |         fs::create_dir(root.as_path()).is_ok();
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stdout] 
[INFO] [stderr] warning: `basic_xlsx_writer` (lib) generated 16 warnings
[INFO] [stdout] running 0 tests
[INFO] [stderr] warning: `basic_xlsx_writer` (lib test) generated 16 warnings (16 duplicates)
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.03s
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/basic_xlsx_writer-86935d7e07712ff4)
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests basic_xlsx_writer
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "e8100c838d3c38e65f470c4a5fa9495c5fc29c7fdc119041b622f557a7a0a56f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e8100c838d3c38e65f470c4a5fa9495c5fc29c7fdc119041b622f557a7a0a56f", kill_on_drop: false }`
[INFO] [stdout] e8100c838d3c38e65f470c4a5fa9495c5fc29c7fdc119041b622f557a7a0a56f