Module materialize.cargo

A pure Python metadata parser for Cargo, Rust's package manager.

See the Cargo documentation for details. Only the features that are presently necessary to support this repository are implemented.

# Copyright Materialize, Inc. All rights reserved.
#
# Use of this software is governed by the Business Source License
# included in the LICENSE file at the root of this repository.
#
# As of the Change Date specified in that file, in accordance with
# the Business Source License, use of this software will be governed
# by the Apache License, Version 2.0.

"""A pure Python metadata parser for Cargo, Rust's package manager.

See the [Cargo] documentation for details. Only the features that are presently
necessary to support this repository are implemented.

[Cargo]: https://doc.rust-lang.org/cargo/
"""

from materialize import git
from pathlib import Path
from typing import Set
import semver
import toml


class Crate:
    """A Cargo crate.

    A crate directory must contain a `Cargo.toml` file with `package.name` and
    `package.version` keys.

    Args:
        root: The path to the root of the workspace.
        path: The path to the crate directory.

    Attributes:
        name: The name of the crate.
        version: The version of the crate.
    """

    def __init__(self, root: Path, path: Path):
        self.root = root
        with open(path / "Cargo.toml") as f:
            config = toml.load(f)
        self.name = config["package"]["name"]
        self.version = semver.VersionInfo.parse(config["package"]["version"])
        self.path = path
        self.path_dependencies: Set[str] = set()
        for dep_type in ["build-dependencies", "dependencies"]:
            if dep_type in config:
                self.path_dependencies.update(
                    c.get("package", name)
                    for name, c in config[dep_type].items()
                    if "path" in c
                )
        self.bins = []
        if "bin" in config:
            for bin in config["bin"]:
                self.bins.append(bin["name"])
        if (path / "src" / "main.rs").exists():
            self.bins.append(self.name)
        for path in (path / "src" / "bin").glob("*.rs"):
            self.bins.append(path.stem)

    def inputs(self) -> Set[str]:
        """Compute the files that can impact the compilation of this crate.

        Note that the returned list may have false positives (i.e., include
        files that do not in fact impact the compilation of this crate), but it
        is not believed to have false negatives.

        Returns:
            inputs: A list of input files, relative to the root of the
                Cargo workspace.
        """
        # NOTE(benesch): it would be nice to have fine-grained tracking of only
        # exactly the files that go into a Rust crate, but doing this properly
        # requires parsing Rust code, and we don't want to force a dependency on
        # a Rust toolchain for users running demos. Instead, we assume that all†
        # files in a crate's directory are inputs to that crate.
        #
        # † As a development convenience, we omit mzcompose and mzcompose.yml
        # files within a crate. This is technically incorrect if someone writes
        # `include!("mzcompose.yml")`, but that seems like a crazy thing to do.
        return git.expand_globs(
            self.root,
            f"{self.path}/**",
            f":(exclude){self.path}/mzcompose",
            f":(exclude){self.path}/mzcompose.yml",
        )


class Workspace:
    """A Cargo workspace.

    A workspace directory must contain a `Cargo.toml` file with a
    `workspace.members` key.

    Args:
        root: The path to the root of the workspace.
    """

    def __init__(self, root: Path):
        with open(root / "Cargo.toml") as f:
            config = toml.load(f)

        self.crates = {}
        for path in config["workspace"]["members"]:
            crate = Crate(root, root / path)
            self.crates[crate.name] = crate

    def crate_for_bin(self, bin: str) -> Crate:
        """Find the crate containing the named binary.

        Args:
            bin: The name of the binary to find.

        Raises:
            ValueError: The named binary did not exist in exactly one crate in
                the Cargo workspace.
        """
        out = None
        for crate in self.crates.values():
            for b in crate.bins:
                if b == bin:
                    if out is not None:
                        raise ValueError(
                            f"bin {bin} appears more than once in cargo workspace"
                        )
                    out = crate
        if out is None:
            raise ValueError(f"bin {bin} does not exist in cargo workspace")
        return out

    def transitive_path_dependencies(self, crate: Crate) -> Set[Crate]:
        """Collects the transitive path dependencies of the requested crate.

        Note that only _path_ dependencies are collected. Other types of
        dependencies, like registry or Git dependencies, are not collected.

        Args:
            crate: The crate object from which to start the dependency crawl.

        Returns:
            crate_set: A set of all of the crates in this Cargo workspace upon
                which the input crate depended upon, whether directly or
                transitively.

        Raises:
            IndexError: The input crate did not exist.
        """
        deps = set()

        def visit(c: Crate) -> None:
            deps.add(c)
            for d in c.path_dependencies:
                visit(self.crates[d])

        visit(crate)
        return deps

Classes

class Crate (root: pathlib.Path, path: pathlib.Path)

A Cargo crate.

A crate directory must contain a Cargo.toml file with package.name and package.version keys.

Args

root

The path to the root of the workspace.

path

The path to the crate directory.

Attributes

name

The name of the crate.

version

The version of the crate.

Expand source code Browse git

class Crate:
    """A Cargo crate.

    A crate directory must contain a `Cargo.toml` file with `package.name` and
    `package.version` keys.

    Args:
        root: The path to the root of the workspace.
        path: The path to the crate directory.

    Attributes:
        name: The name of the crate.
        version: The version of the crate.
    """

    def __init__(self, root: Path, path: Path):
        self.root = root
        with open(path / "Cargo.toml") as f:
            config = toml.load(f)
        self.name = config["package"]["name"]
        self.version = semver.VersionInfo.parse(config["package"]["version"])
        self.path = path
        self.path_dependencies: Set[str] = set()
        for dep_type in ["build-dependencies", "dependencies"]:
            if dep_type in config:
                self.path_dependencies.update(
                    c.get("package", name)
                    for name, c in config[dep_type].items()
                    if "path" in c
                )
        self.bins = []
        if "bin" in config:
            for bin in config["bin"]:
                self.bins.append(bin["name"])
        if (path / "src" / "main.rs").exists():
            self.bins.append(self.name)
        for path in (path / "src" / "bin").glob("*.rs"):
            self.bins.append(path.stem)

    def inputs(self) -> Set[str]:
        """Compute the files that can impact the compilation of this crate.

        Note that the returned list may have false positives (i.e., include
        files that do not in fact impact the compilation of this crate), but it
        is not believed to have false negatives.

        Returns:
            inputs: A list of input files, relative to the root of the
                Cargo workspace.
        """
        # NOTE(benesch): it would be nice to have fine-grained tracking of only
        # exactly the files that go into a Rust crate, but doing this properly
        # requires parsing Rust code, and we don't want to force a dependency on
        # a Rust toolchain for users running demos. Instead, we assume that all†
        # files in a crate's directory are inputs to that crate.
        #
        # † As a development convenience, we omit mzcompose and mzcompose.yml
        # files within a crate. This is technically incorrect if someone writes
        # `include!("mzcompose.yml")`, but that seems like a crazy thing to do.
        return git.expand_globs(
            self.root,
            f"{self.path}/**",
            f":(exclude){self.path}/mzcompose",
            f":(exclude){self.path}/mzcompose.yml",
        )

Methods

def inputs(self) -> Set[str]

Compute the files that can impact the compilation of this crate.

Note that the returned list may have false positives (i.e., include files that do not in fact impact the compilation of this crate), but it is not believed to have false negatives.

Returns

inputs

A list of input files, relative to the root of the Cargo workspace.

Expand source code Browse git

def inputs(self) -> Set[str]:
    """Compute the files that can impact the compilation of this crate.

    Note that the returned list may have false positives (i.e., include
    files that do not in fact impact the compilation of this crate), but it
    is not believed to have false negatives.

    Returns:
        inputs: A list of input files, relative to the root of the
            Cargo workspace.
    """
    # NOTE(benesch): it would be nice to have fine-grained tracking of only
    # exactly the files that go into a Rust crate, but doing this properly
    # requires parsing Rust code, and we don't want to force a dependency on
    # a Rust toolchain for users running demos. Instead, we assume that all†
    # files in a crate's directory are inputs to that crate.
    #
    # † As a development convenience, we omit mzcompose and mzcompose.yml
    # files within a crate. This is technically incorrect if someone writes
    # `include!("mzcompose.yml")`, but that seems like a crazy thing to do.
    return git.expand_globs(
        self.root,
        f"{self.path}/**",
        f":(exclude){self.path}/mzcompose",
        f":(exclude){self.path}/mzcompose.yml",
    )

class Workspace (root: pathlib.Path)

A Cargo workspace.

A workspace directory must contain a Cargo.toml file with a workspace.members key.

Args

root

The path to the root of the workspace.

Expand source code Browse git

class Workspace:
    """A Cargo workspace.

    A workspace directory must contain a `Cargo.toml` file with a
    `workspace.members` key.

    Args:
        root: The path to the root of the workspace.
    """

    def __init__(self, root: Path):
        with open(root / "Cargo.toml") as f:
            config = toml.load(f)

        self.crates = {}
        for path in config["workspace"]["members"]:
            crate = Crate(root, root / path)
            self.crates[crate.name] = crate

    def crate_for_bin(self, bin: str) -> Crate:
        """Find the crate containing the named binary.

        Args:
            bin: The name of the binary to find.

        Raises:
            ValueError: The named binary did not exist in exactly one crate in
                the Cargo workspace.
        """
        out = None
        for crate in self.crates.values():
            for b in crate.bins:
                if b == bin:
                    if out is not None:
                        raise ValueError(
                            f"bin {bin} appears more than once in cargo workspace"
                        )
                    out = crate
        if out is None:
            raise ValueError(f"bin {bin} does not exist in cargo workspace")
        return out

    def transitive_path_dependencies(self, crate: Crate) -> Set[Crate]:
        """Collects the transitive path dependencies of the requested crate.

        Note that only _path_ dependencies are collected. Other types of
        dependencies, like registry or Git dependencies, are not collected.

        Args:
            crate: The crate object from which to start the dependency crawl.

        Returns:
            crate_set: A set of all of the crates in this Cargo workspace upon
                which the input crate depended upon, whether directly or
                transitively.

        Raises:
            IndexError: The input crate did not exist.
        """
        deps = set()

        def visit(c: Crate) -> None:
            deps.add(c)
            for d in c.path_dependencies:
                visit(self.crates[d])

        visit(crate)
        return deps

Methods

def crate_for_bin(self, bin: str) -> Crate

Find the crate containing the named binary.

Args

bin

The name of the binary to find.

Raises

ValueError

The named binary did not exist in exactly one crate in the Cargo workspace.

Expand source code Browse git

def crate_for_bin(self, bin: str) -> Crate:
    """Find the crate containing the named binary.

    Args:
        bin: The name of the binary to find.

    Raises:
        ValueError: The named binary did not exist in exactly one crate in
            the Cargo workspace.
    """
    out = None
    for crate in self.crates.values():
        for b in crate.bins:
            if b == bin:
                if out is not None:
                    raise ValueError(
                        f"bin {bin} appears more than once in cargo workspace"
                    )
                out = crate
    if out is None:
        raise ValueError(f"bin {bin} does not exist in cargo workspace")
    return out

def transitive_path_dependencies(self, crate: Crate) -> Set[Crate]

Collects the transitive path dependencies of the requested crate.

Note that only path dependencies are collected. Other types of dependencies, like registry or Git dependencies, are not collected.

Args

crate

The crate object from which to start the dependency crawl.

Returns

crate_set

A set of all of the crates in this Cargo workspace upon which the input crate depended upon, whether directly or transitively.

Raises

IndexError

The input crate did not exist.

Expand source code Browse git

def transitive_path_dependencies(self, crate: Crate) -> Set[Crate]:
    """Collects the transitive path dependencies of the requested crate.

    Note that only _path_ dependencies are collected. Other types of
    dependencies, like registry or Git dependencies, are not collected.

    Args:
        crate: The crate object from which to start the dependency crawl.

    Returns:
        crate_set: A set of all of the crates in this Cargo workspace upon
            which the input crate depended upon, whether directly or
            transitively.

    Raises:
        IndexError: The input crate did not exist.
    """
    deps = set()

    def visit(c: Crate) -> None:
        deps.add(c)
        for d in c.path_dependencies:
            visit(self.crates[d])

    visit(crate)
    return deps