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use crate::errors::{HgError, HgResultExt, IoResultExt};
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use crate::repo::Repo;
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|
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fn parse(bytes: &[u8]) -> Result<Vec<String>, HgError> {
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// The Python code reading this file uses `str.splitlines`
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// which looks for a number of line separators (even including a couple of
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|
// non-ASCII ones), but Python code writing it always uses `\n`.
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|
let lines = bytes.split(|&byte| byte == b'\n');
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|
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lines
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.filter(|line| !line.is_empty())
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|
.map(|line| {
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|
|
// Python uses Unicode `str.isalnum` but feature names are all
|
|
|
// ASCII
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|
|
if line[0].is_ascii_alphanumeric() && line.is_ascii() {
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|
Ok(String::from_utf8(line.into()).unwrap())
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|
} else {
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|
|
Err(HgError::corrupted("parse error in 'requires' file"))
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|
}
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|
})
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|
.collect()
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|
}
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|
pub fn load(repo: &Repo) -> Result<Vec<String>, HgError> {
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|
if let Some(bytes) = repo
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|
|
.hg_vfs()
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|
|
.read("requires")
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|
|
.for_file("requires".as_ref())
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|
|
.io_not_found_as_none()?
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|
|
{
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|
|
parse(&bytes)
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|
|
} else {
|
|
|
// Treat a missing file the same as an empty file.
|
|
|
// From `mercurial/localrepo.py`:
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|
|
// > requires file contains a newline-delimited list of
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|
|
// > features/capabilities the opener (us) must have in order to use
|
|
|
// > the repository. This file was introduced in Mercurial 0.9.2,
|
|
|
// > which means very old repositories may not have one. We assume
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|
|
// > a missing file translates to no requirements.
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|
|
Ok(Vec::new())
|
|
|
}
|
|
|
}
|
|
|
|
|
|
pub fn check(repo: &Repo) -> Result<(), HgError> {
|
|
|
for feature in load(repo)? {
|
|
|
if !SUPPORTED.contains(&&*feature) {
|
|
|
// TODO: collect and all unknown features and include them in the
|
|
|
// error message?
|
|
|
return Err(HgError::UnsupportedFeature(format!(
|
|
|
"repository requires feature unknown to this Mercurial: {}",
|
|
|
feature
|
|
|
)));
|
|
|
}
|
|
|
}
|
|
|
Ok(())
|
|
|
}
|
|
|
|
|
|
// TODO: set this to actually-supported features
|
|
|
const SUPPORTED: &[&str] = &[
|
|
|
"dotencode",
|
|
|
"fncache",
|
|
|
"generaldelta",
|
|
|
"revlogv1",
|
|
|
"sparserevlog",
|
|
|
"store",
|
|
|
// As of this writing everything rhg does is read-only.
|
|
|
// When it starts writing to the repository, it’ll need to either keep the
|
|
|
// persistent nodemap up to date or remove this entry:
|
|
|
"persistent-nodemap",
|
|
|
];
|
|
|
|
