Trailing slash in destination path results in strange behaviour

[vale summit]

Version: 0.15.1
The trailing slash in the destination path of withFile in containerB results in the file having the name of the destination directory.
Shouldn't the output of containerB and containerC be the same?
Code:

import { connect } from '@dagger.io/dagger';

async function main() {
  await connect(async (client) => {
    const containerA = client.container().from('alpine').withWorkdir('/app').withExec(['touch', 'a']);
    const containerB = client
      .container()
      .from('alpine')
      .withWorkdir('/app')
      .withFile('/app/', containerA.file('/app/a'));
    const containerC = client
      .container()
      .from('alpine')
      .withWorkdir('/app')
      .withFile('/app/a', containerA.file('/app/a'));
    console.log(await containerB.withExec(['tree', '/app']).stdout());
    console.log(await containerC.withExec(['tree', '/app']).stdout());
  });
}

main();

Output:

/app
└── app

0 directories, 1 files

/app
└── a

0 directories, 1 files

[hollow quiver]

Yes, that's expected. This follows the same behavior as Dockerfile's COPY instruction. ref: https://docs.docker.com/reference/dockerfile/#copy

[vale summit]

I see, but why doesn't it throw an error when /app already exists (it can't write the file to /app) but creates a file in this directory?

Also the trailing slash should indicate to create it in the directory in the first place.

[hollow quiver]

🤷‍♂️. I'd assume this probably has a long and interesting discussion in the Docker world, lol

[vale summit]

@hollow quiver Was fixed with the newest release: https://github.com/dagger/dagger/pull/9457