Improve strategy for selecting targets to be scraped for examples
### What does this PR try to resolve?
After #10343, we have identified a clear set of conditions for whether a particular target should be considered by `-Zrustdoc-scrape-examples`. These conditions are described more clearly in #11425.
However, after some testing with complex Cargo workspaces (e.g. [wasmtime](https://github.com/bytecodealliance/wasmtime/)), I realized that the current approach of modifying the `CompileFilter` did not correctly implement this new specification. For example, a target with `doc = false` should not be scraped by default since it is not a documented unit, but the current approach would potentially include such a target for scraping.
This PR provides a new approach which I believe correctly implements the specification:
1. `generate_targets` is called with the same parameters except the `mode` which becomes `CompileMode::Docscrape` instead of `CompileMode::Doc`. `filter_default_targets` generates the same targets for `Docscrape` as for `Doc`.
2. Inside `generate_targets`, an initial set of `Proposal`s are created. This set of proposals is extended with further proposals based on targets identified as `doc-scrape-examples = true`, or Example targets where possible.
This PR subsumes #11423, and also fixes#10571.
### How should we test and review this PR?
I have added another test `docscrape::only_scrape_documented_targets` to verify that only documented or explicitly-enabled targets are included for scraping.
r? `@weihanglo`
Add error message when `cargo fix` on an empty repo
### What does this PR try to resolve?
close https://github.com/rust-lang/cargo/issues/11380
Add error message when `cargo fix` on an empty repo.
### How should we test and review this PR?
- [x] unit test
```sh
set -eux
cargo +nightly new repro
cd repro
echo "fn main() { let _ = 0.clone(); }" > src/main.rs
cargo fix
```
Store the sparse+ prefix in the SourceId for sparse registries
#11209 added a new `SourceKind::SparseRegistry` and removed the `sparse+` prefix from the URLs stored in the `SourceId`.
The removal of the `sparse+` prefix from the URLs in the `SourceId` has led to several bugs, since registry URLs no longer round-trip through a `SourceId`. The most recent one I found was that the example configuration generated by `cargo vendor` did not include the `sparse+` prefix. Any place that calls the `.url()` method on a `SourceId` potentially has this bug.
This change puts the `sparse+` prefix back in the URL stored in the `SourceId`, but keeps the new `SourceKind::SparseRegistry`.
A test is added for doing `cargo vendor` on an alternative registry using the sparse protocol.
add newline char to `cargo install .` error message for easier reading.
I just noticed the `cargo install .` error message was not formatted very nicely.
Just added a newline char to make it cleaner.
Thanks
Change rustdoc-scrape-examples to be a target-level configuration
This PR addresses issues raised in rust-lang/cargo#9525. Specifically:
1. It enables examples to be scraped from `#[test]` functions, by passing additional flags to Rustdoc to ensure that these functions aren't ignored by rustc.
2. It moves the `arg` from `-Z rustdoc-scrape-examples={arg}` into a target-level configuration that can be added to Cargo.toml.
The added test `scrape_examples_configure_target` shows a concrete example. In short, examples will be default scraped from Example and Lib targets. Then the user can enable or disable scraping like so:
```toml
[lib]
doc-scrape-examples = false
[[test]]
name = "my_test"
doc-scrape-examples = true
```
Add warning when `cargo tree -i <spec>` can not find packages
### What does this PR try to resolve?
close https://github.com/rust-lang/cargo/issues/11315
Add warning when `cargo tree -i <spec>` can not find packages.
### How should we test and review this PR?
Please run the unit test.
Clean profile, patch, and replace in cargo remove
### What does this PR try to resolve?
This PR is part of the continued work on cargo remove (#11099, see deferred work).
After a successful removal of a dependency, clean up the profile, patch, and replace sections to remove all references to it.
**Note** the GC process was expanded to clean up not just references to the dependencies just removed, but also references of all dependencies. This was because there's not an easy way to determine which dependencies correspond to the given TOML keys, without either 1) figuring that out before the removal (therefore having to predict the behavior), or 2) returning that information from the remove function (somewhat unorthodox for an op).
### How should we review and test this PR?
Verify that the implementation makes sense and that the tests are sufficient.
fix: return non UTF-8 error message
Fixes https://github.com/rust-lang/cargo/issues/11311
### Test Steps
1. Create a new empty Git repository
2. Create a `.gitignore` that is not valid UTF-8, for instance `printf '\xFF\xFE' > .gitignore`
3. `cargo init`
test(publish): Cover more wait-for-publish cases
These came from trying to guess what cases are causing problems in #11314. Unfortunately, can't reproduce it so far but figured it'd be good to keep these around.
