##// END OF EJS Templates
rust: fix unsound `OwningDirstateMap`...
rust: fix unsound `OwningDirstateMap` As per the previous patch, `OwningDirstateMap` is unsound. Self-referential structs are difficult to implement correctly in Rust since the compiler is free to move structs around as much as it wants to. They are also very rarely needed in practice, so the state-of-the-art on how they should be done within the Rust rules is still a bit new. The crate `ouroboros` is an attempt at providing a safe way (in the Rust sense) of declaring self-referential structs. It is getting a lot attention and was improved very quickly when soundness issues were found in the past: rather than relying on our own (limited) review circle, we might as well use the de-facto common crate to fix this problem. This will give us a much better chance of finding issues should any new ones be discovered as well as the benefit of fewer `unsafe` APIs of our own. I was starting to think about how I would present a safe API to the old struct but soon realized that the callback-based approach was already done in `ouroboros`, along with a lot more care towards refusing incorrect structs. In short: we don't return a mutable reference to the `DirstateMap` anymore, we expect users of its API to pass a `FnOnce` that takes the map as an argument. This allows our `OwningDirstateMap` to control the input and output lifetimes of the code that modifies it to prevent such issues. Changing to `ouroboros` meant changing every API with it, but it is relatively low churn in the end. It correctly identified the example buggy modification of `copy_map_insert` outlined in the previous patch as violating the borrow rules. Differential Revision: https://phab.mercurial-scm.org/D12429

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r49284:9b0e1f64 default
r49857:c9f44fc9 stable
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files.rs
101 lines | 3.1 KiB | application/rls-services+xml | RustLexer
use crate::error::CommandError;
use crate::ui::Ui;
use crate::utils::path_utils::RelativizePaths;
use clap::Arg;
use hg::errors::HgError;
use hg::operations::list_rev_tracked_files;
use hg::operations::Dirstate;
use hg::repo::Repo;
use hg::utils::hg_path::HgPath;
pub const HELP_TEXT: &str = "
List tracked files.
Returns 0 on success.
";
pub fn args() -> clap::App<'static, 'static> {
clap::SubCommand::with_name("files")
.arg(
Arg::with_name("rev")
.help("search the repository as it is in REV")
.short("-r")
.long("--revision")
.value_name("REV")
.takes_value(true),
)
.about(HELP_TEXT)
}
pub fn run(invocation: &crate::CliInvocation) -> Result<(), CommandError> {
let relative = invocation.config.get(b"ui", b"relative-paths");
if relative.is_some() {
return Err(CommandError::unsupported(
"non-default ui.relative-paths",
));
}
let rev = invocation.subcommand_args.value_of("rev");
let repo = invocation.repo?;
// It seems better if this check is removed: this would correspond to
// automatically enabling the extension if the repo requires it.
// However we need this check to be in sync with vanilla hg so hg tests
// pass.
if repo.has_sparse()
&& invocation.config.get(b"extensions", b"sparse").is_none()
{
return Err(CommandError::unsupported(
"repo is using sparse, but sparse extension is not enabled",
));
}
if let Some(rev) = rev {
if repo.has_narrow() {
return Err(CommandError::unsupported(
"rhg files -r <rev> is not supported in narrow clones",
));
}
let files = list_rev_tracked_files(repo, rev).map_err(|e| (e, rev))?;
display_files(invocation.ui, repo, files.iter())
} else {
// The dirstate always reflects the sparse narrowspec, so if
// we only have sparse without narrow all is fine.
// If we have narrow, then [hg files] needs to check if
// the store narrowspec is in sync with the one of the dirstate,
// so we can't support that without explicit code.
if repo.has_narrow() {
return Err(CommandError::unsupported(
"rhg files is not supported in narrow clones",
));
}
let distate = Dirstate::new(repo)?;
let files = distate.tracked_files()?;
display_files(invocation.ui, repo, files.into_iter().map(Ok))
}
}
fn display_files<'a>(
ui: &Ui,
repo: &Repo,
files: impl IntoIterator<Item = Result<&'a HgPath, HgError>>,
) -> Result<(), CommandError> {
let mut stdout = ui.stdout_buffer();
let mut any = false;
let relativize = RelativizePaths::new(repo)?;
for result in files {
let path = result?;
stdout.write_all(&relativize.relativize(path))?;
stdout.write_all(b"\n")?;
any = true;
}
stdout.flush()?;
if any {
Ok(())
} else {
Err(CommandError::Unsuccessful)
}
}