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Differential D9862

rust: Exclude empty node prefixes
ClosedPublic

Authored by SimonSapin on Jan 25 2021, 4:12 PM.

Details

Reviewers
Alphare
pulkit
Group Reviewers
hg-reviewers
Commits
rHGe61c2dc6e1c2: rust: Exclude empty node prefixes
Summary

We presumably don’t want --rev "" to select every single revision,
even though the empty string is a prefix of all strings.

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

SimonSapin created this revision.Jan 25 2021, 4:12 PM
SimonSapin updated this revision to Diff 25350.Jan 28 2021, 2:38 PM
Alphare accepted this revision.Jan 29 2021, 6:35 AM
pulkit accepted this revision.Jan 31 2021, 2:38 PM
This revision is now accepted and ready to land.Jan 31 2021, 2:38 PM
SimonSapin added a commit: rHGe61c2dc6e1c2: rust: Exclude empty node prefixes.Jan 31 2021, 3:26 PM
Closed by commit rHGe61c2dc6e1c2: rust: Exclude empty node prefixes (authored by SimonSapin). · Explain Why
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

PathPackages
Mrust/hg-core/src/revlog/node.rs (6 lines)

Diff 25416

rust/hg-core/src/revlog/node.rs

/// Similarly to `hex::decode`, can be used with Unicode string types /// Similarly to `hex::decode`, can be used with Unicode string types
/// (`String`, `&str`) as well as bytes. /// (`String`, `&str`) as well as bytes.
/// ///
/// To be used in FFI and I/O only, in order to facilitate future /// To be used in FFI and I/O only, in order to facilitate future
/// changes of hash format. /// changes of hash format.
pub fn from_hex(hex: impl AsRef<[u8]>) -> Result<Self, FromHexError> { pub fn from_hex(hex: impl AsRef<[u8]>) -> Result<Self, FromHexError> {
let hex = hex.as_ref(); let hex = hex.as_ref();
let len = hex.len(); let len = hex.len();
if len > NODE_NYBBLES_LENGTH { if len > NODE_NYBBLES_LENGTH || len == 0 {
return Err(FromHexError); return Err(FromHexError);
} }
let is_odd = len % 2 == 1; let is_odd = len % 2 == 1;
let even_part = if is_odd { &hex[..len - 1] } else { hex }; let even_part = if is_odd { &hex[..len - 1] } else { hex };
let mut buf: Vec<u8> = let mut buf: Vec<u8> =
Vec::from_hex(&even_part).map_err(|_| FromHexError)?; Vec::from_hex(&even_part).map_err(|_| FromHexError)?;
pub fn len(&self) -> usize { pub fn len(&self) -> usize {
if self.is_odd { if self.is_odd {
self.buf.len() * 2 - 1 self.buf.len() * 2 - 1
} else { } else {
self.buf.len() * 2 self.buf.len() * 2
} }
} }
pub fn is_empty(&self) -> bool {
self.len() == 0
}
pub fn is_prefix_of(&self, node: &Node) -> bool { pub fn is_prefix_of(&self, node: &Node) -> bool {
if self.is_odd { if self.is_odd {
let buf = self.buf; let buf = self.buf;
let last_pos = buf.len() - 1; let last_pos = buf.len() - 1;
node.data.starts_with(buf.split_at(last_pos).0) node.data.starts_with(buf.split_at(last_pos).0)
&& node.data[last_pos] >> 4 == buf[last_pos] >> 4 && node.data[last_pos] >> 4 == buf[last_pos] >> 4
} else { } else {
node.data.starts_with(self.buf) node.data.starts_with(self.buf)