Warn if using hash in git URL, Fixes #8241

[mjarkk]

This fixes an issue where if the user wants to set the git rev but doesn't know how and as results tries to set the ref in the url hash as also shown when downloading the dependency.
Now cargo returns a warning notifying the user about the correct way to set the ref.

Fixes #8241

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @ehuss (or someone else) soon.

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[alexcrichton]

Thanks! Could a test be added for this as well?

[ehuss]

Oh, and another thought, it might be clearer to specifically mention the URL fragment, and also say where the rev should go. Maybe something like this:

format!("URL fragment `#{}` in git URL is ignored for dependency ({}). \
    If you were trying to specify a specific git revision, \
    use `rev = \"{}\"` in the dependency declaration.", fragment, name_in_toml, fragment);

[mjarkk]

@alexcrichton I've added a test

[ehuss]

Thanks!

@bors r+

[bors]

📌 Commit 91f6617 has been approved by ehuss

[bors]

⌛ Testing commit 91f6617 with merge 40ebd52...

[bors]

☀️ Test successful - checks-azure
Approved by: ehuss
Pushing 40ebd52 to master...

[rofrol]

Added this to Cargo.toml:

typed-html = { git = "https://github.com/bodil/typed-html", rev = "4c13ecca" }
typed-html-macros = { git = "https://github.com/bodil/typed-html", rev = "4c13ecca" }

Now I got urls like ?rev=4c13ecca#4c13ecca:

   Compiling typed-html-macros v0.2.2 (https://github.com/bodil/typed-html?rev=4c13ecca#4c13ecca)
   Compiling typed-html v0.2.2 (https://github.com/bodil/typed-html?rev=4c13ecca#4c13ecca)