cargo new --template ignores/replaces/overwrites .gitignore

[ssokolow]

While investigating another flaw in --template, I discovered the following undesired behaviour when generating a test project from my boilerplate for CLI utilities:

diff -u -ur ../rust-cli-boilerplate/.gitignore ./.gitignore
--- ../rust-cli-boilerplate/.gitignore  2017-03-09 13:33:13.345285768 -0500
+++ ./.gitignore        2017-03-23 11:41:35.619386304 -0400
@@ -1,2 +1,3 @@
-/callgrind.out.justfile
-/target
+target/
+**/*.rs.bk
+Cargo.lock

While I admit I forgot to exclude *.rs.bk, the rest is unhelpful.

What's worse is that I don't see how this actually helps anything, given that, for a project template, there isn't really much of a purpose to .gitignore outside of being passed on to the generated projects. (It's not as if the template's Cargo.toml is valid TOML before the placeholder for the author list gets substituted.)

You'll also notice that it's adding Cargo.lock to the .gitignore when this is specifically intended as --bin project template, not a --lib one, so that's not helpful either.

I think a proper solution would be to only generate a .gitignore if none is present in the template

As-is, I'm forced to go back to what I used before... a wrapper script.

[alexcrichton]

cc @ehiggs @gchp

[ehiggs]

If I understand correctly, your template has a .gitignore but it wasn't used by cargo new and some other .gitignore was generated. And the expected behaviour is that it should use the .gitignore from your template verbatim. Makes sense to me.

[ssokolow]

Yes, that's correct.

The template contains a .gitignore which ignores the target folder and the temporary file used by my justfile for passing profiles from callgrind to kcachegrind.

cargo new instead populates new projects with a .gitignore which ignores target, *.rs.bk, and Cargo.lock. (The latter being a problem because not all templates are going to be --lib templates.)

[alexcrichton]

Yeah makes sense to me as well to use the .gitignore from templates over the built-in one, thanks for the report @ssokolow!

[ehiggs]

Templates have been removed pending an RFC. There is a pre-RFC thread here. I think this can be closed for now.

[alexcrichton]

Thanks @ehiggs!