tools/crates/gnrt/crates.rs - chromium/src - Git at Google

 // Copyright 2022 The Chromium Authors.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 //! Utilities to handle vendored third-party crates.

 use crate::manifest;

 use std::fmt::{self, Display};
 use std::fs;
 use std::io;
 use std::path::{Path, PathBuf};
 use std::str::FromStr;

 /// A normalized version as used in third_party/rust crate paths.
 ///
 /// A crate version is identified by the major version, if it's >= 1, or the
 /// minor version, if the major version is 0. There is a many-to-one
 /// relationship between crate versions and epochs.
 #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
 pub enum Epoch {
     /// Epoch with major version == 0. The field is the minor version. It is an
     /// error to use 0: methods may panic in this case.
     Minor(u64),
     /// Epoch with major version >= 1. It is an error to use 0: methods may
     /// panic in this case.
     Major(u64),
 }

 impl Epoch {
     /// Get the semver version string for this Epoch. This will only have a
     /// non-zero major component, or a zero major component and a non-zero minor
     /// component. Note this differs from Epoch's `fmt::Display` impl.
     pub fn to_version_string(&self) -> String {
         match *self {
             // These should never return Err since formatting an integer is
             // infallible.
             Epoch::Minor(minor) => {
                 assert_ne!(minor, 0);
                 format!("0.{minor}")
             }
             Epoch::Major(major) => {
                 assert_ne!(major, 0);
                 format!("{major}")
             }
         }
     }

     /// Compute the Epoch from a `semver::Version`. This is useful since we can
     /// parse versions from `cargo_metadata` and in Cargo.toml files using the
     /// `semver` library.
     pub fn from_version(version: &semver::Version) -> Self {
         match version.major {
             0 => Self::Minor(version.minor.try_into().unwrap()),
             x => Self::Major(x.try_into().unwrap()),
         }
     }

     /// Get the requested epoch from a supported dependency version string.
     /// `req` should be a version request as used in Cargo.toml's [dependencies]
     /// section.
     ///
     /// `req` must use the default strategy as defined in
     /// https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html#specifying-dependencies-from-cratesio
     pub fn from_version_req_str(req: &str) -> Self {
         // For convenience, leverage semver::VersionReq for parsing even
         // though we don't need the full expressiveness.
         let req = semver::VersionReq::from_str(req).unwrap();
         // We require the spec to have exactly one comparator, which must use
         // the default strategy.
         assert_eq!(req.comparators.len(), 1);
         let comp: &semver::Comparator = &req.comparators[0];
         // Caret is semver's name for the default strategy.
         assert_eq!(comp.op, semver::Op::Caret);
         match (comp.major, comp.minor) {
             (0, Some(0) | None) => panic!("invalid version req {req}"),
             (0, Some(x)) => Epoch::Minor(x),
             (x, _) => Epoch::Major(x),
         }
     }
 }

 // This gives us a ToString implementation for free.
 impl Display for Epoch {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match *self {
             // These should never return Err since formatting an integer is
             // infallible.
             Epoch::Minor(minor) => {
                 assert_ne!(minor, 0);
                 f.write_fmt(format_args!("v0_{minor}")).unwrap()
             }
             Epoch::Major(major) => {
                 assert_ne!(major, 0);
                 f.write_fmt(format_args!("v{major}")).unwrap()
             }
         }

         Ok(())
     }
 }

 impl FromStr for Epoch {
     type Err = EpochParseError;

     /// A valid input string is of the form:
     /// * "v{i}", where i >= 1, or
     /// * "v0_{i}", where i >= 1
     ///
     /// Any other string is invalid. If the "v" is missing, there are extra
     /// underscore-separated components, or there are two numbers but both
     /// are 0 or greater than zero are all invalid strings.
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         // Split off the "v" prefix.
         let mut iter = s.split_inclusive('v');
         if iter.next() != Some("v") {
             return Err(EpochParseError::BadFormat);
         }
         let s = iter.next().ok_or(EpochParseError::BadFormat)?;
         if iter.next() != None {
             return Err(EpochParseError::BadFormat);
         }

         // Split the major and minor version numbers.
         let mut parts = s.split('_');
         let major: Option<u64> =
             parts.next().map(|s| s.parse().map_err(EpochParseError::InvalidInt)).transpose()?;
         let minor: Option<u64> =
             parts.next().map(|s| s.parse().map_err(EpochParseError::InvalidInt)).transpose()?;

         // Get the final epoch, checking that the (major, minor) pair is valid.
         let result = match (major, minor) {
             (Some(0), Some(0)) => Err(EpochParseError::BadVersion),
             (Some(0), Some(minor)) => Ok(Epoch::Minor(minor)),
             (Some(major), None) => Ok(Epoch::Major(major)),
             (Some(_), Some(_)) => Err(EpochParseError::BadVersion),
             (None, None) => Err(EpochParseError::BadFormat),
             _ => unreachable!(),
         }?;

         // Ensure there's no remaining parts.
         if parts.next() == None { Ok(result) } else { Err(EpochParseError::BadFormat) }
     }
 }

 #[derive(Clone, Debug, Eq, PartialEq)]
 pub enum EpochParseError {
     /// An integer could not be parsed where expected.
     InvalidInt(std::num::ParseIntError),
     /// The string was not formatted correctly. It was missing the 'v' prefix,
     /// was missing the '_' separator, or had a tail after the last integer.
     BadFormat,
     /// The epoch had an invalid combination of versions: e.g. "v0_0", "v1_0",
     /// "v1_1".
     BadVersion,
 }

 impl Display for EpochParseError {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         use EpochParseError::*;
         match self {
             InvalidInt(parse_int_error) => parse_int_error.fmt(f),
             BadFormat => f.write_str("epoch string had incorrect format"),
             BadVersion => f.write_str("epoch string had invalid version"),
         }
     }
 }

 impl std::error::Error for EpochParseError {}

 /// A crate name normalized to the format we use in //third_party.
 #[derive(Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
 pub struct NormalizedName(String);

 impl NormalizedName {
     /// Wrap a normalized name, checking that it is valid.
     pub fn new(normalized_name: &str) -> Option<NormalizedName> {
         let converted_name = Self::from_crate_name(normalized_name);
         if converted_name.0 == normalized_name { Some(converted_name) } else { None }
     }

     /// Normalize a crate name. `crate_name` is the name Cargo uses to refer to
     /// the crate.
     pub fn from_crate_name(crate_name: &str) -> NormalizedName {
         NormalizedName(
             crate_name
                 .chars()
                 .map(|c| match c {
                     '-' | '.' => '_',
                     c => c,
                 })
                 .collect(),
         )
     }
 }

 impl fmt::Display for NormalizedName {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.write_str(&self.0)
     }
 }

 /// Identifies a vendored third-party crate.
 #[derive(Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
 pub struct ThirdPartyCrate {
     /// The upstream name as specified in its Cargo.toml.
     pub name: String,
     /// The crate's epoch, as defined by `Epoch`.
     pub epoch: Epoch,
 }

 impl ThirdPartyCrate {
     /// The location of this crate's directory, including its source subdir and
     /// build files, relative to the third-party Rust crate directory. Crates
     /// are laid out according to their name and epoch.
     pub fn build_path(&self) -> PathBuf {
         let mut path = PathBuf::new();
         path.push(NormalizedName::from_crate_name(&self.name).0);
         path.push(self.epoch.to_string());
         path
     }

     /// The location of this crate's source relative to the third-party Rust
     /// crate directory.
     pub fn crate_path(&self) -> PathBuf {
         let mut path = self.build_path();
         path.push("crate");
         path
     }

     /// Unique but arbitrary name for this (crate, epoch) pair. Suitable for use
     /// in Cargo.toml [patch] sections.
     pub fn patch_name(&self) -> String {
         format!("{}_{}", self.name, self.epoch)
     }
 }

 impl fmt::Display for ThirdPartyCrate {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.write_fmt(format_args!("{} {}", self.name, self.epoch))
     }
 }

 /// Traverse vendored third-party crates and collect the set of names and
 /// epochs. Each `ThirdPartyCrate` entry is paired with the package metadata
 /// from its manifest. The returned list is in unspecified order.
 pub fn collect_third_party_crates<P: AsRef<Path>>(
     crates_path: P,
 ) -> io::Result<Vec<(ThirdPartyCrate, manifest::CargoPackage)>> {
     let mut crates = Vec::new();

     for crate_dir in fs::read_dir(crates_path)? {
         // Look at each crate directory.
         let crate_dir: fs::DirEntry = crate_dir?;
         if !crate_dir.file_type()?.is_dir() {
             continue;
         }

         let crate_path = crate_dir.path();

         // Ensure the path has a valid name: is UTF8, has our normalized format.
         let normalized_name = path_as_str(crate_path.file_name().unwrap())?;
         into_io_result(NormalizedName::new(normalized_name).ok_or_else(|| {
             format!("unnormalized crate name in path {}", crate_path.to_string_lossy())
         }))?;

         for epoch_dir in fs::read_dir(crate_dir.path())? {
             // Look at each epoch of the crate we have checked in.
             let epoch_dir: fs::DirEntry = epoch_dir?;
             if !crate_dir.file_type()?.is_dir() {
                 continue;
             }

             let epoch_path = epoch_dir.path();
             let epoch_name = path_as_str(epoch_path.file_name().unwrap())?;
             let epoch = match Epoch::from_str(epoch_name) {
                 Ok(epoch) => epoch,
                 // Skip if we can't parse the directory as a valid epoch.
                 Err(_) => continue,
             };

             // Try to read the Cargo.toml, since we need the package name. The
             // directory name on disk is normalized but we need to refer to the
             // package the way Cargo expects.
             let manifest_path = epoch_path.join("crate/Cargo.toml");
             let manifest_contents = match fs::read_to_string(&manifest_path) {
                 Ok(s) => s,
                 Err(e) => match e.kind() {
                     // Skip this directory and log a message if a Cargo.toml
                     // doesn't exist.
                     io::ErrorKind::NotFound => {
                         println!(
                             "Warning: directory name parsed as valid epoch but \
                             contained no Cargo.toml: {}",
                             manifest_path.to_string_lossy()
                         );
                         continue;
                     }
                     _ => return Err(e),
                 },
             };
             let manifest: manifest::CargoManifest = toml::de::from_str(&manifest_contents).unwrap();
             let package_name = manifest.package.name.clone();

             crates.push((ThirdPartyCrate { name: package_name, epoch }, manifest.package));
         }
     }

     Ok(crates)
 }

 /// Utility to read a path as a `&str` with an informative error message if it
 /// had invalid UTF8.
 fn path_as_str<T: AsRef<Path> + ?Sized>(path: &T) -> io::Result<&str> {
     let path = path.as_ref();
     into_io_result(
         path.to_str().ok_or_else(|| format!("invalid utf8 in path {}", path.to_string_lossy())),
     )
 }

 /// Utility to convert a `Result<T, E>` into `io::Result<T>` for any compatible
 /// error type `E`.
 fn into_io_result<T, E: Into<Box<dyn std::error::Error + Send + Sync>>>(
     result: Result<T, E>,
 ) -> io::Result<T> {
     result.map_err(|e| io::Error::new(io::ErrorKind::Other, e))
 }
	// Copyright 2022 The Chromium Authors.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	//! Utilities to handle vendored third-party crates.

	use crate::manifest;

	use std::fmt::{self, Display};
	use std::fs;
	use std::io;
	use std::path::{Path, PathBuf};
	use std::str::FromStr;

	/// A normalized version as used in third_party/rust crate paths.
	///
	/// A crate version is identified by the major version, if it's >= 1, or the
	/// minor version, if the major version is 0. There is a many-to-one
	/// relationship between crate versions and epochs.
	#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
	pub enum Epoch {
	/// Epoch with major version == 0. The field is the minor version. It is an
	/// error to use 0: methods may panic in this case.
	Minor(u64),
	/// Epoch with major version >= 1. It is an error to use 0: methods may
	/// panic in this case.
	Major(u64),
	}

	impl Epoch {
	/// Get the semver version string for this Epoch. This will only have a
	/// non-zero major component, or a zero major component and a non-zero minor
	/// component. Note this differs from Epoch's `fmt::Display` impl.
	pub fn to_version_string(&self) -> String {
	match *self {
	// These should never return Err since formatting an integer is
	// infallible.
	Epoch::Minor(minor) => {
	assert_ne!(minor, 0);
	format!("0.{minor}")
	}
	Epoch::Major(major) => {
	assert_ne!(major, 0);
	format!("{major}")
	}
	}
	}

	/// Compute the Epoch from a `semver::Version`. This is useful since we can
	/// parse versions from `cargo_metadata` and in Cargo.toml files using the
	/// `semver` library.
	pub fn from_version(version: &semver::Version) -> Self {
	match version.major {
	0 => Self::Minor(version.minor.try_into().unwrap()),
	x => Self::Major(x.try_into().unwrap()),
	}
	}

	/// Get the requested epoch from a supported dependency version string.
	/// `req` should be a version request as used in Cargo.toml's [dependencies]
	/// section.
	///
	/// `req` must use the default strategy as defined in
	/// https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html#specifying-dependencies-from-cratesio
	pub fn from_version_req_str(req: &str) -> Self {
	// For convenience, leverage semver::VersionReq for parsing even
	// though we don't need the full expressiveness.
	let req = semver::VersionReq::from_str(req).unwrap();
	// We require the spec to have exactly one comparator, which must use
	// the default strategy.
	assert_eq!(req.comparators.len(), 1);
	let comp: &semver::Comparator = &req.comparators[0];
	// Caret is semver's name for the default strategy.
	assert_eq!(comp.op, semver::Op::Caret);
	match (comp.major, comp.minor) {
	(0, Some(0) \| None) => panic!("invalid version req {req}"),
	(0, Some(x)) => Epoch::Minor(x),
	(x, _) => Epoch::Major(x),
	}
	}
	}

	// This gives us a ToString implementation for free.
	impl Display for Epoch {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
	match *self {
	// These should never return Err since formatting an integer is
	// infallible.
	Epoch::Minor(minor) => {
	assert_ne!(minor, 0);
	f.write_fmt(format_args!("v0_{minor}")).unwrap()
	}
	Epoch::Major(major) => {
	assert_ne!(major, 0);
	f.write_fmt(format_args!("v{major}")).unwrap()
	}
	}

	Ok(())
	}
	}

	impl FromStr for Epoch {
	type Err = EpochParseError;

	/// A valid input string is of the form:
	/// * "v{i}", where i >= 1, or
	/// * "v0_{i}", where i >= 1
	///
	/// Any other string is invalid. If the "v" is missing, there are extra
	/// underscore-separated components, or there are two numbers but both
	/// are 0 or greater than zero are all invalid strings.
	fn from_str(s: &str) -> Result<Self, Self::Err> {
	// Split off the "v" prefix.
	let mut iter = s.split_inclusive('v');
	if iter.next() != Some("v") {
	return Err(EpochParseError::BadFormat);
	}
	let s = iter.next().ok_or(EpochParseError::BadFormat)?;
	if iter.next() != None {
	return Err(EpochParseError::BadFormat);
	}

	// Split the major and minor version numbers.
	let mut parts = s.split('_');
	let major: Option<u64> =
	parts.next().map(\|s\| s.parse().map_err(EpochParseError::InvalidInt)).transpose()?;
	let minor: Option<u64> =
	parts.next().map(\|s\| s.parse().map_err(EpochParseError::InvalidInt)).transpose()?;

	// Get the final epoch, checking that the (major, minor) pair is valid.
	let result = match (major, minor) {
	(Some(0), Some(0)) => Err(EpochParseError::BadVersion),
	(Some(0), Some(minor)) => Ok(Epoch::Minor(minor)),
	(Some(major), None) => Ok(Epoch::Major(major)),
	(Some(_), Some(_)) => Err(EpochParseError::BadVersion),
	(None, None) => Err(EpochParseError::BadFormat),
	_ => unreachable!(),
	}?;

	// Ensure there's no remaining parts.
	if parts.next() == None { Ok(result) } else { Err(EpochParseError::BadFormat) }
	}
	}

	#[derive(Clone, Debug, Eq, PartialEq)]
	pub enum EpochParseError {
	/// An integer could not be parsed where expected.
	InvalidInt(std::num::ParseIntError),
	/// The string was not formatted correctly. It was missing the 'v' prefix,
	/// was missing the '_' separator, or had a tail after the last integer.
	BadFormat,
	/// The epoch had an invalid combination of versions: e.g. "v0_0", "v1_0",
	/// "v1_1".
	BadVersion,
	}

	impl Display for EpochParseError {
	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
	use EpochParseError::*;
	match self {
	InvalidInt(parse_int_error) => parse_int_error.fmt(f),
	BadFormat => f.write_str("epoch string had incorrect format"),
	BadVersion => f.write_str("epoch string had invalid version"),
	}
	}
	}

	impl std::error::Error for EpochParseError {}

	/// A crate name normalized to the format we use in //third_party.
	#[derive(Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
	pub struct NormalizedName(String);

	impl NormalizedName {
	/// Wrap a normalized name, checking that it is valid.
	pub fn new(normalized_name: &str) -> Option<NormalizedName> {
	let converted_name = Self::from_crate_name(normalized_name);
	if converted_name.0 == normalized_name { Some(converted_name) } else { None }
	}

	/// Normalize a crate name. `crate_name` is the name Cargo uses to refer to
	/// the crate.
	pub fn from_crate_name(crate_name: &str) -> NormalizedName {
	NormalizedName(
	crate_name
	.chars()
	.map(\|c\| match c {
	'-' \| '.' => '_',
	c => c,
	})
	.collect(),
	)
	}
	}

	impl fmt::Display for NormalizedName {
	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
	f.write_str(&self.0)
	}
	}

	/// Identifies a vendored third-party crate.
	#[derive(Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
	pub struct ThirdPartyCrate {
	/// The upstream name as specified in its Cargo.toml.
	pub name: String,
	/// The crate's epoch, as defined by `Epoch`.
	pub epoch: Epoch,
	}

	impl ThirdPartyCrate {
	/// The location of this crate's directory, including its source subdir and
	/// build files, relative to the third-party Rust crate directory. Crates
	/// are laid out according to their name and epoch.
	pub fn build_path(&self) -> PathBuf {
	let mut path = PathBuf::new();
	path.push(NormalizedName::from_crate_name(&self.name).0);
	path.push(self.epoch.to_string());
	path
	}

	/// The location of this crate's source relative to the third-party Rust
	/// crate directory.
	pub fn crate_path(&self) -> PathBuf {
	let mut path = self.build_path();
	path.push("crate");
	path
	}

	/// Unique but arbitrary name for this (crate, epoch) pair. Suitable for use
	/// in Cargo.toml [patch] sections.
	pub fn patch_name(&self) -> String {
	format!("{}_{}", self.name, self.epoch)
	}
	}

	impl fmt::Display for ThirdPartyCrate {
	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
	f.write_fmt(format_args!("{} {}", self.name, self.epoch))
	}
	}

	/// Traverse vendored third-party crates and collect the set of names and
	/// epochs. Each `ThirdPartyCrate` entry is paired with the package metadata
	/// from its manifest. The returned list is in unspecified order.
	pub fn collect_third_party_crates<P: AsRef<Path>>(
	crates_path: P,
	) -> io::Result<Vec<(ThirdPartyCrate, manifest::CargoPackage)>> {
	let mut crates = Vec::new();

	for crate_dir in fs::read_dir(crates_path)? {
	// Look at each crate directory.
	let crate_dir: fs::DirEntry = crate_dir?;
	if !crate_dir.file_type()?.is_dir() {
	continue;
	}

	let crate_path = crate_dir.path();

	// Ensure the path has a valid name: is UTF8, has our normalized format.
	let normalized_name = path_as_str(crate_path.file_name().unwrap())?;
	into_io_result(NormalizedName::new(normalized_name).ok_or_else(\|\| {
	format!("unnormalized crate name in path {}", crate_path.to_string_lossy())
	}))?;

	for epoch_dir in fs::read_dir(crate_dir.path())? {
	// Look at each epoch of the crate we have checked in.
	let epoch_dir: fs::DirEntry = epoch_dir?;
	if !crate_dir.file_type()?.is_dir() {
	continue;
	}

	let epoch_path = epoch_dir.path();
	let epoch_name = path_as_str(epoch_path.file_name().unwrap())?;
	let epoch = match Epoch::from_str(epoch_name) {
	Ok(epoch) => epoch,
	// Skip if we can't parse the directory as a valid epoch.
	Err(_) => continue,
	};

	// Try to read the Cargo.toml, since we need the package name. The
	// directory name on disk is normalized but we need to refer to the
	// package the way Cargo expects.
	let manifest_path = epoch_path.join("crate/Cargo.toml");
	let manifest_contents = match fs::read_to_string(&manifest_path) {
	Ok(s) => s,
	Err(e) => match e.kind() {
	// Skip this directory and log a message if a Cargo.toml
	// doesn't exist.
	io::ErrorKind::NotFound => {
	println!(
	"Warning: directory name parsed as valid epoch but \
	contained no Cargo.toml: {}",
	manifest_path.to_string_lossy()
	);
	continue;
	}
	_ => return Err(e),
	},
	};
	let manifest: manifest::CargoManifest = toml::de::from_str(&manifest_contents).unwrap();
	let package_name = manifest.package.name.clone();

	crates.push((ThirdPartyCrate { name: package_name, epoch }, manifest.package));
	}
	}

	Ok(crates)
	}

	/// Utility to read a path as a `&str` with an informative error message if it
	/// had invalid UTF8.
	fn path_as_str<T: AsRef<Path> + ?Sized>(path: &T) -> io::Result<&str> {
	let path = path.as_ref();
	into_io_result(
	path.to_str().ok_or_else(\|\| format!("invalid utf8 in path {}", path.to_string_lossy())),
	)
	}

	/// Utility to convert a `Result<T, E>` into `io::Result<T>` for any compatible
	/// error type `E`.
	fn into_io_result<T, E: Into<Box<dyn std::error::Error + Send + Sync>>>(
	result: Result<T, E>,
	) -> io::Result<T> {
	result.map_err(\|e\| io::Error::new(io::ErrorKind::Other, e))
	}