[INFO] fetching crate basic_xlsx_writer 0.1.3...
[INFO] checking basic_xlsx_writer-0.1.3 against try#8de4b308b608cded0ebccf658a0fc719bce87d4e for pr-89056
[INFO] extracting crate basic_xlsx_writer 0.1.3 into /workspace/builds/worker-42/source
[INFO] validating manifest of crates.io crate basic_xlsx_writer 0.1.3 on toolchain 8de4b308b608cded0ebccf658a0fc719bce87d4e
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "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-42/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-42/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-42/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9e504ac9a1579ae7a9d425768ba5d703bdd0720dd2d44b411c51013c7c31a484
[INFO] running `Command { std: "docker" "start" "-a" "9e504ac9a1579ae7a9d425768ba5d703bdd0720dd2d44b411c51013c7c31a484", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9e504ac9a1579ae7a9d425768ba5d703bdd0720dd2d44b411c51013c7c31a484", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9e504ac9a1579ae7a9d425768ba5d703bdd0720dd2d44b411c51013c7c31a484", kill_on_drop: false }`
[INFO] [stdout] 9e504ac9a1579ae7a9d425768ba5d703bdd0720dd2d44b411c51013c7c31a484
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-42/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-42/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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e9750c832e93e84b635d3707d4700e477a235be442b2ca121ef38c35810f3a2d
[INFO] running `Command { std: "docker" "start" "-a" "e9750c832e93e84b635d3707d4700e477a235be442b2ca121ef38c35810f3a2d", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.102
[INFO] [stderr]    Compiling cc v1.0.70
[INFO] [stderr]    Compiling pkg-config v0.3.19
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling crc32fast v1.2.1
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking podio v0.1.7
[INFO] [stderr]    Compiling miniz_oxide v0.4.4
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]    Compiling bzip2-sys v0.1.11+1.0.8
[INFO] [stderr]     Checking flate2 v1.0.22
[INFO] [stderr]     Checking msdos_time v0.1.6
[INFO] [stderr]     Checking bzip2 v0.3.3
[INFO] [stderr]     Checking zip v0.4.2
[INFO] [stderr]     Checking 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:143:38
[INFO] [stdout]     |
[INFO] [stdout] 143 |     pub fn write(&self, writer: &mut Write) -> Result<()> {
[INFO] [stdout]     |                                      ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                                             ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                                    ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                       ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                             ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                           ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                  ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                          ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                 ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                 ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                   ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                                ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                               ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                     ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                      ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                                             ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                                    ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                       ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                             ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                           ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                  ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                          ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                 ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                 ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                   ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                                ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                               ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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]     |                                     ^^^^^ help: use `dyn`: `dyn Write`
[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] 
[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: 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 5.39s
[INFO] running `Command { std: "docker" "inspect" "e9750c832e93e84b635d3707d4700e477a235be442b2ca121ef38c35810f3a2d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e9750c832e93e84b635d3707d4700e477a235be442b2ca121ef38c35810f3a2d", kill_on_drop: false }`
[INFO] [stdout] e9750c832e93e84b635d3707d4700e477a235be442b2ca121ef38c35810f3a2d