This is an archive of the discontinued Mercurial Phabricator instance.

Status	Author	Revision
Closed	SimonSapin	D9938 rust: use HgError in ConfigError
Closed	SimonSapin	D9906 rust: Fold find_root and check_requirements into Repo::find
Closed	SimonSapin	D9905 rhg: Simplify CommandError based on its use
Closed	SimonSapin	D9904 rust: replace ToString impls with Display
Closed	SimonSapin	D9897 rust: use HgError in RevlogError and Vfs
Closed	SimonSapin	D9896 rust: replace RequirementsError with HgError
Closed	SimonSapin	D9895 rhg: Print an error message in more cases
Closed	SimonSapin	D9894 rust: Remove DirstateParseError and ListDirstateTrackedFilesError
Closed	SimonSapin	D9893 rust: Replace DirstatePackError with HgError
Closed	SimonSapin	D9892 rust: Introduce an `HgError` enum for common error cases
Closed	SimonSapin	D9877 rust: remove three enums that were identical to `RevlogError`
Closed	SimonSapin	D9876 rhg: replace `map_*_error` functions with `From` impls
Closed	SimonSapin	D9875 rust: replace trivial `impl From …` with `#[derive(derive_more::From)]`
Closed	SimonSapin	D9874 rust: remove `FooError` structs with only `kind: FooErrorKind` enum field
Closed	SimonSapin	D9873 rhg: centralize parsing of `--rev` CLI arguments
Closed	SimonSapin	D9864 rust: Remove hex parsing from the nodemap
Closed	SimonSapin	D9863 rust: Make NodePrefix allocation-free and Copy, remove NodePrefixRef
Closed	SimonSapin	D9862 rust: Exclude empty node prefixes
Closed	SimonSapin	D9861 rust: Simplify error type for reading hex node IDs
Closed	SimonSapin	D9860 rust: replace Node::encode_hex with std::fmt::LowerHex

Diff 25432

rust/hg-core/src/errors.rs

This file was added.

				use std::fmt;

				/// Common error cases that can happen in many different APIs
				#[derive(Debug)]
				pub enum HgError {
				IoError {
				error: std::io::Error,
				context: IoErrorContext,
				},

				/// A file under `.hg/` normally only written by Mercurial
				///
				/// The given string is a short explanation for users, not intended to be
				/// machine-readable.
				CorruptedRepository(String),

				/// The respository or requested operation involves a feature not
				/// supported by the Rust implementation. Falling back to the Python
				/// implementation may or may not work.
				///
				/// The given string is a short explanation for users, not intended to be
				/// machine-readable.
				UnsupportedFeature(String),
				}

				/// Details about where an I/O error happened
				#[derive(Debug, derive_more::From)]
				pub enum IoErrorContext {
				/// A filesystem operation returned `std::io::Error`
				#[from]
				File(std::path::PathBuf),
				/// `std::env::current_dir` returned `std::io::Error`
				CurrentDir,
				}

				impl HgError {
				pub fn corrupted(explanation: impl Into<String>) -> Self {
				HgError::CorruptedRepository(explanation.into())
				}
				}

				// TODO: use `DisplayBytes` instead to show non-Unicode filenames losslessly?
				impl fmt::Display for HgError {
				fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
				match self {
				HgError::IoError { error, context } => {
				write!(f, "{}: {}", error, context)
				}
				HgError::CorruptedRepository(explanation) => {
				write!(f, "corrupted repository: {}", explanation)
				}
				HgError::UnsupportedFeature(explanation) => {
				write!(f, "unsupported feature: {}", explanation)
				}
				}
				}
				}

				// TODO: use `DisplayBytes` instead to show non-Unicode filenames losslessly?
				impl fmt::Display for IoErrorContext {
				fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
				match self {
				IoErrorContext::File(path) => path.display().fmt(f),
				IoErrorContext::CurrentDir => f.write_str("current directory"),
				}
				}
				}

				pub trait IoResultExt<T> {
				/// Annotate a possible I/O error as related to a file at the given path.
				///
				/// This allows printing something like “File not found: example.txt”
				/// instead of just “File not found”.
				///
				/// Converts a `Result` with `std::io::Error` into one with `HgError`.
				fn for_file(self, path: &std::path::Path) -> Result<T, HgError>;
				}

				impl<T> IoResultExt<T> for std::io::Result<T> {
				fn for_file(self, path: &std::path::Path) -> Result<T, HgError> {
				self.map_err(\|error\| HgError::IoError {
				error,
				context: IoErrorContext::File(path.to_owned()),
				})
				}
				}

				pub trait HgResultExt<T> {
				/// Handle missing files separately from other I/O error cases.
				///
				/// Wraps the `Ok` type in an `Option`:
				///
				/// * `Ok(x)` becomes `Ok(Some(x))`
				/// * An I/O "not found" error becomes `Ok(None)`
				/// * Other errors are unchanged
				fn io_not_found_as_none(self) -> Result<Option<T>, HgError>;
				}

				impl<T> HgResultExt<T> for Result<T, HgError> {
				fn io_not_found_as_none(self) -> Result<Option<T>, HgError> {
				match self {
				Ok(x) => Ok(Some(x)),
				Err(HgError::IoError { error, .. })
				if error.kind() == std::io::ErrorKind::NotFound =>
				{
				Ok(None)
				}
				Err(other_error) => Err(other_error),
				}
				}
				}

rust/hg-core/src/lib.rs

	// Copyright 2018-2020 Georges Racinet <georges.racinet@octobus.net>			// Copyright 2018-2020 Georges Racinet <georges.racinet@octobus.net>
	// and Mercurial contributors			// and Mercurial contributors
	//			//
	// This software may be used and distributed according to the terms of the			// This software may be used and distributed according to the terms of the
	// GNU General Public License version 2 or any later version.			// GNU General Public License version 2 or any later version.
	mod ancestors;			mod ancestors;
	pub mod dagops;			pub mod dagops;
				pub mod errors;
	pub use ancestors::{AncestorsIterator, LazyAncestors, MissingAncestors};			pub use ancestors::{AncestorsIterator, LazyAncestors, MissingAncestors};
	mod dirstate;			mod dirstate;
	pub mod discovery;			pub mod discovery;
	pub mod requirements;			pub mod requirements;
	pub mod testing; // unconditionally built, for use from integration tests			pub mod testing; // unconditionally built, for use from integration tests
	pub use dirstate::{			pub use dirstate::{
	dirs_multiset::{DirsMultiset, DirsMultisetIter},			dirs_multiset::{DirsMultiset, DirsMultisetIter},
	dirstate_map::DirstateMap,			dirstate_map::DirstateMap,

Diff	ID	Description	Created	Lint	Unit
Base		Base
Diff 1	25316		Jan 27 2021, 4:12 PM	★	★
Diff 2	25432	rHG39e9407820ac571d6040b8672c32bb943f7438aa	Jan 27 2021, 7:19 AM	★	★

This is an archive of the discontinued Mercurial Phabricator instance.

rust: Introduce an `HgError` enum for common error casesClosedPublic

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Diff 25432

rust/hg-core/src/errors.rs

rust/hg-core/src/lib.rs

rust: Introduce an `HgError` enum for common error cases
ClosedPublic

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