[INFO] fetching crate png-achunk 0.1.0...
[INFO] testing png-achunk-0.1.0 against try#c2e32f1c9652b13ed99608599c1e855462f421f3 for pr-146098-8
[INFO] extracting crate png-achunk 0.1.0 into /workspace/builds/worker-0-tc2/source
[INFO] removed /workspace/builds/worker-0-tc2/source/rust-toolchain.toml
[INFO] started tweaking crates.io crate png-achunk 0.1.0
[INFO] finished tweaking crates.io crate png-achunk 0.1.0
[INFO] tweaked toml for crates.io crate png-achunk 0.1.0 written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate png-achunk 0.1.0 on toolchain c2e32f1c9652b13ed99608599c1e855462f421f3
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 57 packages to latest compatible versions
[INFO] [stderr]       Adding image v0.24.9 (available: v0.25.8)
[INFO] [stderr]       Adding png v0.17.16 (available: v0.18.0)
[INFO] [stderr]       Adding thiserror v1.0.69 (available: v2.0.17)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 422f2efdfe0760a638e3b708396be932d7c3556ba23738530d35b369356ace2b
[INFO] running `Command { std: "docker" "start" "-a" "422f2efdfe0760a638e3b708396be932d7c3556ba23738530d35b369356ace2b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "422f2efdfe0760a638e3b708396be932d7c3556ba23738530d35b369356ace2b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "422f2efdfe0760a638e3b708396be932d7c3556ba23738530d35b369356ace2b", kill_on_drop: false }`
[INFO] [stdout] 422f2efdfe0760a638e3b708396be932d7c3556ba23738530d35b369356ace2b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 33813a6c00984d04d7eaec0b02c560330dca63c57fb4e59e36e69b931325b1fb
[INFO] running `Command { std: "docker" "start" "-a" "33813a6c00984d04d7eaec0b02c560330dca63c57fb4e59e36e69b931325b1fb", kill_on_drop: false }`
[INFO] [stderr]    Compiling simd-adler32 v0.3.7
[INFO] [stderr]    Compiling adler2 v2.0.1
[INFO] [stderr]    Compiling crc32fast v1.5.0
[INFO] [stderr]    Compiling zerocopy v0.8.27
[INFO] [stderr]    Compiling either v1.15.0
[INFO] [stderr]    Compiling weezl v0.1.12
[INFO] [stderr]    Compiling bitflags v1.3.2
[INFO] [stderr]    Compiling bytemuck v1.24.0
[INFO] [stderr]    Compiling lebe v0.5.3
[INFO] [stderr]    Compiling num-traits v0.2.19
[INFO] [stderr]    Compiling bit_field v0.10.3
[INFO] [stderr]    Compiling color_quant v1.1.0
[INFO] [stderr]    Compiling byteorder v1.5.0
[INFO] [stderr]    Compiling syn v2.0.110
[INFO] [stderr]    Compiling ascii v1.1.0
[INFO] [stderr]    Compiling miniz_oxide v0.8.9
[INFO] [stderr]    Compiling zune-inflate v0.2.54
[INFO] [stderr]    Compiling fdeflate v0.3.7
[INFO] [stderr]    Compiling rayon v1.11.0
[INFO] [stderr]    Compiling qoi v0.4.1
[INFO] [stderr]    Compiling gif v0.13.3
[INFO] [stderr]    Compiling flate2 v1.1.5
[INFO] [stderr]    Compiling png v0.17.16
[INFO] [stderr]    Compiling jpeg-decoder v0.3.2
[INFO] [stderr]    Compiling tiff v0.9.1
[INFO] [stderr]    Compiling zerocopy-derive v0.8.27
[INFO] [stderr]    Compiling thiserror-impl v1.0.69
[INFO] [stderr]    Compiling thiserror v1.0.69
[INFO] [stderr]    Compiling half v2.7.1
[INFO] [stderr]    Compiling exr v1.74.0
[INFO] [stderr]    Compiling image v0.24.9
[INFO] [stderr]    Compiling png-achunk v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 28.19s
[INFO] running `Command { std: "docker" "inspect" "33813a6c00984d04d7eaec0b02c560330dca63c57fb4e59e36e69b931325b1fb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "33813a6c00984d04d7eaec0b02c560330dca63c57fb4e59e36e69b931325b1fb", kill_on_drop: false }`
[INFO] [stdout] 33813a6c00984d04d7eaec0b02c560330dca63c57fb4e59e36e69b931325b1fb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f822c4f087402191a85109cf1c04ce09271357a8d23275f98a578e663871ab5f
[INFO] running `Command { std: "docker" "start" "-a" "f822c4f087402191a85109cf1c04ce09271357a8d23275f98a578e663871ab5f", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.177
[INFO] [stderr]    Compiling getrandom v0.3.4
[INFO] [stderr]    Compiling once_cell v1.21.3
[INFO] [stderr]    Compiling tempfile v3.23.0
[INFO] [stderr]    Compiling png-achunk v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 3.28s
[INFO] running `Command { std: "docker" "inspect" "f822c4f087402191a85109cf1c04ce09271357a8d23275f98a578e663871ab5f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f822c4f087402191a85109cf1c04ce09271357a8d23275f98a578e663871ab5f", kill_on_drop: false }`
[INFO] [stdout] f822c4f087402191a85109cf1c04ce09271357a8d23275f98a578e663871ab5f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 3fb09480c3fd905378036b87802b23d5728732dad221d67c714cc87fae7f8bfb
[INFO] running `Command { std: "docker" "start" "-a" "3fb09480c3fd905378036b87802b23d5728732dad221d67c714cc87fae7f8bfb", kill_on_drop: false }`
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.09s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/png_achunk-dcea1fa31f1b5f8c)
[INFO] [stdout] running 0 tests
[INFO] [stderr]      Running tests/test.rs (/opt/rustwide/target/debug/deps/test-ea165891f75cc387)
[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] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test test ... ok
[INFO] [stderr]    Doc-tests png_achunk
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.01s
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 3 tests
[INFO] [stdout] test src/lib.rs - (line 53) ... FAILED
[INFO] [stdout] test src/lib.rs - (line 29) ... FAILED
[INFO] [stdout] test src/lib.rs - (line 15) ... FAILED
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout] 
[INFO] [stdout] ---- src/lib.rs - (line 53) stdout ----
[INFO] [stdout] error: expected item, found `$`
[INFO] [stdout]   --> src/lib.rs:54:1
[INFO] [stdout]    |
[INFO] [stdout] 54 | $ gcc test.c -L. -l:libpng_achunk.a -lm -o test
[INFO] [stdout]    | ^ expected item
[INFO] [stdout]    |
[INFO] [stdout]    = note: for a full list of items that can appear in modules, see <https://doc.rust-lang.org/reference/items.html>
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 1 previous error
[INFO] [stdout] 
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] ---- src/lib.rs - (line 29) stdout ----
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:32:65
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_29_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] 31 | // Decode image and ancillary chunks
[INFO] [stdout] 32 | let (image, chunks) = png_achunk::Decoder::from_file("test.png")?.decode_all()?;
[INFO] [stdout]    |                                                                 ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout] 30 ~ fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_29_0() -> Result<(), Box<dyn std::error::Error>> {
[INFO] [stdout] 31 | // Decode image and ancillary chunks
[INFO] [stdout] ...
[INFO] [stdout] 34 | let chunks = png_achunk::Decoder::from_file("test.png")?.decode_ancillary_chunks()?;
[INFO] [stdout] 35 +     Ok(())
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:32:79
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_29_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] 31 | // Decode image and ancillary chunks
[INFO] [stdout] 32 | let (image, chunks) = png_achunk::Decoder::from_file("test.png")?.decode_all()?;
[INFO] [stdout]    |                                                                               ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout] 30 ~ fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_29_0() -> Result<(), Box<dyn std::error::Error>> {
[INFO] [stdout] 31 | // Decode image and ancillary chunks
[INFO] [stdout] ...
[INFO] [stdout] 34 | let chunks = png_achunk::Decoder::from_file("test.png")?.decode_ancillary_chunks()?;
[INFO] [stdout] 35 +     Ok(())
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:34:56
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_29_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 34 | let chunks = png_achunk::Decoder::from_file("test.png")?.decode_ancillary_chunks()?;
[INFO] [stdout]    |                                                        ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout] 30 ~ fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_29_0() -> Result<(), Box<dyn std::error::Error>> {
[INFO] [stdout] 31 | // Decode image and ancillary chunks
[INFO] [stdout] ...
[INFO] [stdout] 34 | let chunks = png_achunk::Decoder::from_file("test.png")?.decode_ancillary_chunks()?;
[INFO] [stdout] 35 +     Ok(())
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:34:83
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_29_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 34 | let chunks = png_achunk::Decoder::from_file("test.png")?.decode_ancillary_chunks()?;
[INFO] [stdout]    |                                                                                   ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout] 30 ~ fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_29_0() -> Result<(), Box<dyn std::error::Error>> {
[INFO] [stdout] 31 | // Decode image and ancillary chunks
[INFO] [stdout] ...
[INFO] [stdout] 34 | let chunks = png_achunk::Decoder::from_file("test.png")?.decode_ancillary_chunks()?;
[INFO] [stdout] 35 +     Ok(())
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0277`.
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] ---- src/lib.rs - (line 15) stdout ----
[INFO] [stdout] error[E0423]: expected value, found crate `image`
[INFO] [stdout]   --> src/lib.rs:23:1
[INFO] [stdout]    |
[INFO] [stdout] 23 | image.write_with_encoder(
[INFO] [stdout]    | ^^^^^
[INFO] [stdout]    |
[INFO] [stdout] help: use the path separator to refer to an item
[INFO] [stdout]    |
[INFO] [stdout] 23 - image.write_with_encoder(
[INFO] [stdout] 23 + image::write_with_encoder(
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:20:60
[INFO] [stdout]    |
[INFO] [stdout] 16 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_15_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 20 | let chunk_type = png_achunk::ChunkType::from_ascii(&"teST")?;
[INFO] [stdout]    |                                                            ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout] 16 ~ fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_15_0() -> Result<(), Box<dyn std::error::Error>> {
[INFO] [stdout] 17 | // Create custom chunk
[INFO] [stdout] ...
[INFO] [stdout] 25 | )?;
[INFO] [stdout] 26 +     Ok(())
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:21:62
[INFO] [stdout]    |
[INFO] [stdout] 16 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_15_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 21 | let chunk = png_achunk::Chunk::new(chunk_type, vec![4, 5, 6])?;
[INFO] [stdout]    |                                                              ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout] 16 ~ fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_15_0() -> Result<(), Box<dyn std::error::Error>> {
[INFO] [stdout] 17 | // Create custom chunk
[INFO] [stdout] ...
[INFO] [stdout] 25 | )?;
[INFO] [stdout] 26 +     Ok(())
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]   --> src/lib.rs:24:49
[INFO] [stdout]    |
[INFO] [stdout] 16 | fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_15_0() {
[INFO] [stdout]    |                                      ---------------------------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 24 |     png_achunk::Encoder::new_to_file("test.png")?.with_custom_chunk(chunk.clone()),
[INFO] [stdout]    |                                                 ^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout]    |
[INFO] [stdout] help: consider adding return type
[INFO] [stdout]    |
[INFO] [stdout] 16 ~ fn main() { #[allow(non_snake_case)] fn _doctest_main_src_lib_rs_15_0() -> Result<(), Box<dyn std::error::Error>> {
[INFO] [stdout] 17 | // Create custom chunk
[INFO] [stdout] ...
[INFO] [stdout] 25 | )?;
[INFO] [stdout] 26 +     Ok(())
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0423.
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout]     src/lib.rs - (line 15)
[INFO] [stdout]     src/lib.rs - (line 29)
[INFO] [stdout]     src/lib.rs - (line 53)
[INFO] [stdout] 
[INFO] [stdout] test result: FAILED. 0 passed; 3 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.18s
[INFO] [stdout] 
[INFO] [stderr] error: doctest failed, to rerun pass `--doc`
[INFO] running `Command { std: "docker" "inspect" "3fb09480c3fd905378036b87802b23d5728732dad221d67c714cc87fae7f8bfb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3fb09480c3fd905378036b87802b23d5728732dad221d67c714cc87fae7f8bfb", kill_on_drop: false }`
[INFO] [stdout] 3fb09480c3fd905378036b87802b23d5728732dad221d67c714cc87fae7f8bfb
