[vcs] cargo new --vcs fossil changes global settings for fossil-scm.

[yasuoohno]

Problem

cargo new --vcs fossil changes global ignore-glob/clean-glob settings for fossil-scm instead of repository local settings.
It will also affect other fossil-scm working copies.

Steps

1. clear global setings `fossil unset ignore-glob --global & fossil unset clean-glob --global
2. create new cargo package with cargo new project_name --vcs fossil
3. global settings has been changed.

Possible Solution(s)

https://github.com/rust-lang/cargo/blob/master/src/cargo/util/vcs.rs#L99-L111

It seems that cargo executes fossil settings on the current working directory for cargo.
If it has to change the local settings of the repository, we need to do it in the project working directory.

just like this?

        ProcessBuilder::new("fossil")
            .cwd(&path)
            .arg("settings")
            .arg("ignore-glob")
            .arg("target")
            .exec()?;

        ProcessBuilder::new("fossil")
            .cwd(&path)
            .arg("settings")
            .arg("clean-glob")
            .arg("target")
            .exec()?;

But it is unversioned settings.
I think it would be better using versioned setting files in the project working directory.

1. create .fossil-settings/ignore-glob and .fossil-settings/clean-glob files.
2. (optional) add configuration files to the repository.
   fossil add .fossil-settings/ignore-glob .fossil-settings/clean-glob

Notes

Output of cargo version:
cargo 1.51.0 (43b129a 2021-03-16)

output of rustup show:
Default host: x86_64-pc-windows-msvc
stable-x86_64-pc-windows-msvc (default)
rustc 1.51.0 (2fd73fabe 2021-03-23)

Output of fossil version:
This is fossil version 2.15.1 [2f901f98b3] 2021-04-08 01:05:44 UTC

[ehuss]

Yea, it seems like it would make sense to have those be repository settings. I don't use fossil, but it sounds reasonable to me to change it.

[PaulDance]

@yasuoohno #9469 hopefully fixed this part of the code. If you have a bit of time to try this out when it lands on nightly, I would love to hear some feedback!

[yasuoohno]

Hi @PaulDance, Thank you for the fix. I'll try this and give you some feedback when I have time.

[yasuoohno]

I confirmed with cargo 1.54.0-nightly.
It works fine as I expected with cargo new --vcs fossil and also cargo init --vcs fossil.

# the global settings are unchanged :-)
$ fossil settings ignore-glob --global
ignore-glob
$ fossil settings clean-glob --global
clean-glob

# and local settings are versionable
$ fossil settings ignore-glob
ignore-glob
  (overridden by contents of file .fossil-settings/ignore-glob)
$ fossil settings clean-glob
clean-glob
  (overridden by contents of file .fossil-settings/clean-glob)

$ cat .fossil-settings/ignore-glob
target
$ cat .fossil-settings/clean-glob
target

Thanks!

[PaulDance]

@yasuoohno Cool, glad to hear it works as expected!