Only gitignore the top level target directory for 'cargo new'

[dylanmckay]

This modifies the default .gitignore for new projects to ignore only the target folder in the crate root.

Without this, you cannot have a target/mod.rs module.

This will also mean that projects with crate dependencies in the same repository will have their target directories recognised by version control. In these cases, the projects should be using workspaces.

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[steveklabnik]

Without this, you cannot have a target/mod.rs module.

Is there a good reason for this? seems like an anti-pattern.

[dylanmckay]

seems like an anti-pattern.

How do you figure?

[steveklabnik]

in general, target is a directory that's for generated files, not source. Source files should be in src, tests, examples, and the like. I'd expect that rm -rf target would be the rough equivalent to cargo clean; you can't even make use of a target/mod.rs without special configuration.

[jonas-schievink]

this is about things like src/target/mod.rs

[alexcrichton]

Thanks for the PR! This has been proposed before, however, and closed due to this making the multi-crate experience work not-as-great by default.

The template is of course just that, a template, and can always be modified to suit an application's needs. I don't think there's going to be a one-size-fits-all here, unfortunately.