Ignore /target instead of any target

[behnam]

When creating a .gitignore file with this line:

target

it will ignore any file/dir named target anywhere in the repo. Meaning, this would also ignore /src/target/, a submodule, and all its content.

To resolve this problem, we should instead ignore the target dir on the top level:

/target

and, if we want to make sure it's only ignored if a dir:

/target/

What do you think?

[alexcrichton]

This has come up a few times before (#3158, #2565, #1952, #1415), but it seems surprising enough that something needs to change! Mind taking a look at some of those linked issues and see if it changes things?

[behnam]

So, this was not an issue before, because target would only match the path in root. But, now that we're in the migration to gitignore-style matching, we will need to update this after State 1.1 of the migration makes it to beta or stable channels.

Keeping this issue open as a tracker for this specific of the migration.

[behnam]

This is already addressed in master:

cargo/src/cargo/ops/cargo_new.rs

Lines 395 to 404 in 62f800f

	// Please ensure that ignore and hgignore are in sync.
	let ignore = ["/target/\n", "**/*.rs.bk\n",
	if !opts.bin { "Cargo.lock\n" } else { "" }]
	.concat();
	// Mercurial glob ignores can't be rooted, so just sticking a 'syntax: glob' at the top of the
	// file will exclude too much. Instead, use regexp-based ignores. See 'hg help ignore' for
	// more.
	let hgignore = ["^target/\n", "glob:*.rs.bk\n",
	if !opts.bin { "glob:Cargo.lock\n" } else { "" }]
	.concat();

PR: #4099