create helper function project_metadata in bootstrap

Signed-off-by: onur-ozkan <work@onurozkan.dev>

Author: onur-ozkan

src/bootstrap/src/core/metadata.rs

@@ -17,25 +17,29 @@ struct Output {
 /// For more information, see the output of
 /// <https://doc.rust-lang.org/nightly/cargo/commands/cargo-metadata.html>
 #[derive(Debug, Deserialize)]
-struct Package {
-    name: String,
-    source: Option<String>,
-    manifest_path: String,
-    dependencies: Vec<Dependency>,
-    targets: Vec<Target>,
+pub(crate) struct Package {
+    pub(crate) name: String,
+    pub(crate) source: Option<String>,
+    pub(crate) manifest_path: String,
+    pub(crate) dependencies: Vec<Dependency>,
+    pub(crate) targets: Vec<Target>,
 }
 
 /// For more information, see the output of
 /// <https://doc.rust-lang.org/nightly/cargo/commands/cargo-metadata.html>
-#[derive(Debug, Deserialize)]
-struct Dependency {
-    name: String,
-    source: Option<String>,
+#[derive(Debug, Deserialize, PartialEq)]
+pub(crate) struct Dependency {
+    pub(crate) name: String,
+    pub(crate) source: Option<String>,
 }
 
 #[derive(Debug, Deserialize)]
-struct Target {
-    kind: Vec<String>,
+pub(crate) struct Target {
+    pub(crate) name: String,
+    pub(crate) kind: Vec<String>,
+    pub(crate) crate_types: Vec<String>,
+    pub(crate) src_path: String,
+    pub(crate) edition: String,
 }
 
 /// Collects and stores package metadata of each workspace members into `build`,
@@ -70,7 +74,7 @@ pub fn build(build: &mut Build) {
 ///
 /// Note that `src/tools/cargo` is no longer a workspace member but we still
 /// treat it as one here, by invoking an additional `cargo metadata` command.
-fn workspace_members(build: &Build) -> impl Iterator<Item = Package> {
+pub(crate) fn workspace_members(build: &Build) -> impl Iterator<Item = Package> {
     let collect_metadata = |manifest_path| {
         let mut cargo = Command::new(&build.initial_cargo);
         cargo
@@ -99,3 +103,33 @@ fn workspace_members(build: &Build) -> impl Iterator<Item = Package> {
 
     packages.into_iter().chain(cargo_package).chain(ra_packages).chain(bootstrap_packages)
 }
+
+/// Invokes `cargo metadata` to get package metadata of whole workspace including the dependencies.
+pub(crate) fn project_metadata(build: &Build) -> impl Iterator<Item = Package> {
+    let collect_metadata = |manifest_path| {
+        let mut cargo = Command::new(&build.initial_cargo);
+        cargo
+            // Will read the libstd Cargo.toml
+            // which uses the unstable `public-dependency` feature.
+            .env("RUSTC_BOOTSTRAP", "1")
+            .arg("metadata")
+            .arg("--format-version")
+            .arg("1")
+            .arg("--manifest-path")
+            .arg(build.src.join(manifest_path));
+        let metadata_output = output(&mut cargo);
+        let Output { packages, .. } = t!(serde_json::from_str(&metadata_output));
+        packages
+    };
+
+    // Collects `metadata.packages` from all workspaces.
+    let packages = collect_metadata("Cargo.toml");
+    let cargo_packages = collect_metadata("src/tools/cargo/Cargo.toml");
+    let ra_packages = collect_metadata("src/tools/rust-analyzer/Cargo.toml");
+    let bootstrap_packages = collect_metadata("src/bootstrap/Cargo.toml");
+
+    // We only care about the root package from `src/tool/cargo` workspace.
+    let cargo_package = cargo_packages.into_iter().find(|pkg| pkg.name == "cargo").into_iter();
+
+    packages.into_iter().chain(cargo_package).chain(ra_packages).chain(bootstrap_packages)
+}