We use this crate to filter out sources that do not need full software clearing,
so are not interested in the dev or build dependencies.

It is possible to identify these clearly with cargo tree by specifying --edges normal flag (other potentially interesting options: no-build, no-dev, no-proc-macro).
Unfortunately, the flag is not available with cargo metadata as discussed in rust-lang/cargo#10718.

Proposition: add an optional boolean flag --exclude-dev-and-build-deps to cargo vendor filterer (alternative: mimic cargo tree edges options).
If the flag is set, after removing the unwanted platforms and tiers, call cargo tree to get a list of packages required for the application with all features.
Iterate over the packages HashMap and remove all entries not present in the list received from cargo tree.

Expected behavior when running on the crate itself: when the flag is set the once_cell dev package shall be removed -> add a unit test.

By default the flag is not active for backwards compatibility.

Current workaround: manually remove development crates (it is annoying)

Let me know what you think and if you agree that this is a good extension for the current crate, I can send a PR implementing this feature.