https://github.com/coadler/cargo-bug-repro

https://github.com/coadler/cargo-bug-repro

Last synced: 13 days ago
JSON representation

• Host: GitHub
• URL: https://github.com/coadler/cargo-bug-repro
• Owner: coadler
• Created: 2021-03-27T01:26:30.000Z (almost 4 years ago)
• Default Branch: master
• Last Pushed: 2021-03-27T01:38:11.000Z (almost 4 years ago)
• Last Synced: 2024-12-23T16:44:33.490Z (16 days ago)
• Language: Shell
• Size: 1.95 KB
• Stars: 1
• Watchers: 2
• Forks: 0
• Open Issues: 1
• Metadata Files:
  • Readme: README.md

Awesome Lists containing this project

README

        
# cargo-bug-repro

In a Dockerfile, when a COPY directive replaces an existing file, `cargo`

still seems to think it's the same file. Only after `touch`ing it does the

cache reset.

See the example Dockerfile:

```Dockerfile

FROM rust:1.51

WORKDIR /src

RUN cargo init

COPY Cargo.toml Cargo.lock ./

RUN cargo build

COPY . .

RUN cargo build

```

```txt

$ docker run -it cargo-bug-broken /bin/bash

root@cbe6d78de04c:/src# ls

Cargo.lock  Cargo.toml	Dockerfile.broken  Dockerfile.fixed  src  target  test.sh

root@cbe6d78de04c:/src# cat src/main.rs

fn main() {

    println!("Goodbye, world!");

}

root@cbe6d78de04c:/src# cargo build

    Finished dev [unoptimized + debuginfo] target(s) in 0.00s

root@cbe6d78de04c:/src# ./target/debug/cargo-bug-repro

Hello, world!

root@cbe6d78de04c:/src# touch src/main.rs

root@cbe6d78de04c:/src# cargo build

   Compiling cargo-bug-repro v0.1.0 (/src)

    Finished dev [unoptimized + debuginfo] target(s) in 0.23s

root@cbe6d78de04c:/src# ./target/debug/cargo-bug-repro

Goodbye, world!

root@cbe6d78de04c:/src#

```

As you can see, touching the file causes the cache to reset. A fixed

Dockerfile looks like this:

```Dockerfile

FROM rust:1.51

WORKDIR /src

RUN cargo init

COPY Cargo.toml Cargo.lock ./

RUN cargo build

COPY . .

RUN touch src/main.rs && cargo build

```

See test.sh for a comparison of running both the broken and fixed

Dockerfiles.