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    use crate::core::compiler::artifact::match_artifacts_kind_with_targets;
    use crate::core::compiler::{CompileKind, RustcTargetData};
    use crate::core::dependency::DepKind;
    use crate::core::package::SerializedPackage;
    use crate::core::resolver::{features::CliFeatures, HasDevUnits, Resolve};
    use crate::core::{Package, PackageId, Workspace};
    use crate::ops::{self, Packages};
    use crate::util::interning::InternedString;
    use crate::util::CargoResult;
    use cargo_platform::Platform;
    use serde::Serialize;
    use std::collections::BTreeMap;
    use std::path::PathBuf;

    const VERSION: u32 = 1;

    pub struct OutputMetadataOptions {
        pub cli_features: CliFeatures,
        pub no_deps: bool,
        pub version: u32,
        pub filter_platforms: Vec<String>,
    }

    /// Loads the manifest, resolves the dependencies of the package to the concrete
    /// used versions - considering overrides - and writes all dependencies in a JSON
    /// format to stdout.
    pub fn output_metadata(ws: &Workspace<'_>, opt: &OutputMetadataOptions) -> CargoResult<ExportInfo> {
        if opt.version != VERSION {
            anyhow::bail!(
                "metadata version {} not supported, only {} is currently supported",
                opt.version,
                VERSION
            );
        }
        let (packages, resolve) = if opt.no_deps {
            let packages = ws.members().map(|pkg| pkg.serialized()).collect();
            (packages, None)
        } else {
            let (packages, resolve) = build_resolve_graph(ws, opt)?;
            (packages, Some(resolve))
        };

        Ok(ExportInfo {
            packages,
            workspace_members: ws.members().map(|pkg| pkg.package_id()).collect(),
            workspace_default_members: ws.default_members().map(|pkg| pkg.package_id()).collect(),
            resolve,
            target_directory: ws.target_dir().into_path_unlocked(),
            version: VERSION,
            workspace_root: ws.root().to_path_buf(),
            metadata: ws.custom_metadata().cloned(),
        })
    }

    /// This is the structure that is serialized and displayed to the user.
    ///
    /// See cargo-metadata.adoc for detailed documentation of the format.
    #[derive(Serialize)]
    pub struct ExportInfo {
        packages: Vec<SerializedPackage>,
        workspace_members: Vec<PackageId>,
        workspace_default_members: Vec<PackageId>,
        resolve: Option<MetadataResolve>,
        target_directory: PathBuf,
        version: u32,
        workspace_root: PathBuf,
        metadata: Option<toml::Value>,
    }

    #[derive(Serialize)]
    struct MetadataResolve {
        nodes: Vec<MetadataResolveNode>,
        root: Option<PackageId>,
    }

    #[derive(Serialize)]
    struct MetadataResolveNode {
        id: PackageId,
        dependencies: Vec<PackageId>,
        deps: Vec<Dep>,
        features: Vec<InternedString>,
    }

    #[derive(Serialize)]
    struct Dep {
        // TODO(bindeps): after -Zbindeps gets stabilized,
        // mark this field as deprecated in the help manual of cargo-metadata
        name: InternedString,
        pkg: PackageId,
        dep_kinds: Vec<DepKindInfo>,
    }

    #[derive(Serialize, PartialEq, Eq, PartialOrd, Ord)]
    struct DepKindInfo {
        kind: DepKind,
        target: Option<Platform>,

        // vvvvv The fields below are introduced for `-Z bindeps`.
        /// What the manifest calls the crate.
        ///
        /// A renamed dependency will show the rename instead of original name.
        // TODO(bindeps): Remove `Option` after -Zbindeps get stabilized.
        #[serde(skip_serializing_if = "Option::is_none")]
        extern_name: Option<InternedString>,
        /// Artifact's crate type, e.g. staticlib, cdylib, bin...
        #[serde(skip_serializing_if = "Option::is_none")]
        artifact: Option<&'static str>,
        /// Equivalent to `{ target = "…" }` in an artifact dependency requirement.
        ///
        /// * If the target points to a custom target JSON file, the path will be absolute.
        /// * If the target is a build assumed target `{ target = "target" }`, it will show as `<target>`.
        #[serde(skip_serializing_if = "Option::is_none")]
        compile_target: Option<InternedString>,
        /// Executable name for an artifact binary dependency.
        #[serde(skip_serializing_if = "Option::is_none")]
        bin_name: Option<String>,
        // ^^^^^ The fields above are introduced for `-Z bindeps`.
    }

    /// Builds the resolve graph as it will be displayed to the user.
    fn build_resolve_graph(
        ws: &Workspace<'_>,
        metadata_opts: &OutputMetadataOptions,
    ) -> CargoResult<(Vec<SerializedPackage>, MetadataResolve)> {
        // TODO: Without --filter-platform, features are being resolved for `host` only.
        // How should this work?
        let requested_kinds =
            CompileKind::from_requested_targets(ws.config(), &metadata_opts.filter_platforms)?;
        let target_data = RustcTargetData::new(ws, &requested_kinds)?;
        // Resolve entire workspace.
        let specs = Packages::All.to_package_id_specs(ws)?;
        let force_all = if metadata_opts.filter_platforms.is_empty() {
            crate::core::resolver::features::ForceAllTargets::Yes
        } else {
            crate::core::resolver::features::ForceAllTargets::No
        };

        // Note that even with --filter-platform we end up downloading host dependencies as well,
        // as that is the behavior of download_accessible.
        let ws_resolve = ops::resolve_ws_with_opts(
            ws,
            &target_data,
            &requested_kinds,
            &metadata_opts.cli_features,
            &specs,
            HasDevUnits::Yes,
            force_all,
        )?;

        let package_map: BTreeMap<PackageId, Package> = ws_resolve
            .pkg_set
            .packages()
            // This is a little lazy, but serde doesn't handle Rc fields very well.
            .map(|pkg| (pkg.package_id(), Package::clone(pkg)))
            .collect();

        // Start from the workspace roots, and recurse through filling out the
        // map, filtering targets as necessary.
        let mut node_map = BTreeMap::new();
        for member_pkg in ws.members() {
            build_resolve_graph_r(
                &mut node_map,
                member_pkg.package_id(),
                &ws_resolve.targeted_resolve,
                &package_map,
                &target_data,
                &requested_kinds,
            )?;
        }
        // Get a Vec of Packages.
        let actual_packages = package_map
            .into_iter()
            .filter_map(|(pkg_id, pkg)| node_map.get(&pkg_id).map(|_| pkg))
            .map(|pkg| pkg.serialized())
            .collect();

        let mr = MetadataResolve {
            nodes: node_map.into_iter().map(|(_pkg_id, node)| node).collect(),
            root: ws.current_opt().map(|pkg| pkg.package_id()),
        };
        Ok((actual_packages, mr))
    }

    fn build_resolve_graph_r(
        node_map: &mut BTreeMap<PackageId, MetadataResolveNode>,
        pkg_id: PackageId,
        resolve: &Resolve,
        package_map: &BTreeMap<PackageId, Package>,
        target_data: &RustcTargetData<'_>,
        requested_kinds: &[CompileKind],
    ) -> CargoResult<()> {
        if node_map.contains_key(&pkg_id) {
            return Ok(());
        }
        // This normalizes the IDs so that they are consistent between the
        // `packages` array and the `resolve` map. This is a bit of a hack to
        // compensate for the fact that
        // SourceKind::Git(GitReference::Branch("master")) is the same as
        // SourceKind::Git(GitReference::DefaultBranch). We want IDs in the JSON
        // to be opaque, and compare with basic string equality, so this will
        // always prefer the style of ID in the Package instead of the resolver.
        // Cargo generally only exposes PackageIds from the Package struct, and
        // AFAIK this is the only place where the resolver variant is exposed.
        //
        // This diverges because the SourceIds created for Packages are built
        // based on the Dependency declaration, but the SourceIds in the resolver
        // are deserialized from Cargo.lock. Cargo.lock may have been generated by
        // an older (or newer!) version of Cargo which uses a different style.
        let normalize_id = |id| -> PackageId { *package_map.get_key_value(&id).unwrap().0 };
        let features = resolve.features(pkg_id).to_vec();

        let deps = {
            let mut dep_metadatas = Vec::new();
            let iter = resolve.deps(pkg_id).filter(|(_dep_id, deps)| {
                if requested_kinds == [CompileKind::Host] {
                    true
                } else {
                    requested_kinds.iter().any(|kind| {
                        deps.iter()
                            .any(|dep| target_data.dep_platform_activated(dep, *kind))
                    })
                }
            });
            for (dep_id, deps) in iter {
                let mut dep_kinds = Vec::new();

                let targets = package_map[&dep_id].targets();

                // Try to get the extern name for lib, or crate name for bins.
                let extern_name = |target| {
                    resolve
                        .extern_crate_name_and_dep_name(pkg_id, dep_id, target)
                        .map(|(ext_crate_name, _)| ext_crate_name)
                };

                let lib_target = targets.iter().find(|t| t.is_lib());

                for dep in deps.iter() {
                    if let Some(target) = lib_target {
                        // When we do have a library target, include them in deps if...
                        let included = match dep.artifact() {
                            // it is not an artifact dep at all
                            None => true,
                            // it is also an artifact dep with `{ …, lib = true }`
                            Some(a) if a.is_lib() => true,
                            _ => false,
                        };
                        // TODO(bindeps): Cargo shouldn't have `extern_name` field
                        // if the user is not using -Zbindeps.
                        // Remove this condition ` after -Zbindeps gets stabilized.
                        let extern_name = if dep.artifact().is_some() {
                            Some(extern_name(target)?)
                        } else {
                            None
                        };
                        if included {
                            dep_kinds.push(DepKindInfo {
                                kind: dep.kind(),
                                target: dep.platform().cloned(),
                                extern_name,
                                artifact: None,
                                compile_target: None,
                                bin_name: None,
                            });
                        }
                    }

                    // No need to proceed if there is no artifact dependency.
                    let Some(artifact_requirements) = dep.artifact() else {
                        continue;
                    };

                    let compile_target = match artifact_requirements.target() {
                        Some(t) => t
                            .to_compile_target()
                            .map(|t| t.rustc_target())
                            // Given that Cargo doesn't know which target it should resolve to,
                            // when an artifact dep is specified with { target = "target" },
                            // keep it with a special "<target>" string,
                            .or_else(|| Some(InternedString::new("<target>"))),
                        None => None,
                    };

                    let target_set =
                        match_artifacts_kind_with_targets(dep, targets, pkg_id.name().as_str())?;
                    dep_kinds.reserve(target_set.len());
                    for (kind, target) in target_set.into_iter() {
                        dep_kinds.push(DepKindInfo {
                            kind: dep.kind(),
                            target: dep.platform().cloned(),
                            extern_name: extern_name(target).ok(),
                            artifact: Some(kind.crate_type()),
                            compile_target,
                            bin_name: target.is_bin().then(|| target.name().to_string()),
                        })
                    }
                }

                dep_kinds.sort();

                let pkg = normalize_id(dep_id);

                let dep = match (lib_target, dep_kinds.len()) {
                    (Some(target), _) => Dep {
                        name: extern_name(target)?,
                        pkg,
                        dep_kinds,
                    },
                    // No lib target exists but contains artifact deps.
                    (None, 1..) => Dep {
                        name: InternedString::new(""),
                        pkg,
                        dep_kinds,
                    },
                    // No lib or artifact dep exists.
                    // Ususally this mean parent depending on non-lib bin crate.
                    (None, _) => continue,
                };

                dep_metadatas.push(dep)
            }
            dep_metadatas
        };

        let dumb_deps: Vec<PackageId> = deps.iter().map(|dep| dep.pkg).collect();
        let to_visit = dumb_deps.clone();
        let node = MetadataResolveNode {
            id: normalize_id(pkg_id),
            dependencies: dumb_deps,
            deps,
            features,
        };
        node_map.insert(pkg_id, node);
        for dep_id in to_visit {
            build_resolve_graph_r(
                node_map,
                dep_id,
                resolve,
                package_map,
                target_data,
                requested_kinds,
            )?;
        }

        Ok(())
    }