refactor(package): make a workspace-shared vcs info builder

This is aimed to cache duplicate works like file system or VCS info lookups.

src/cargo/ops/cargo_package/mod.rs

@@ -225,6 +225,7 @@ fn do_package<'a>(
 
     // Packages need to be created in dependency order, because dependencies must
     // be added to our local overlay before we can create lockfiles that depend on them.
+    let mut vcs_info_builder = vcs::VcsInfoBuilder::new(ws, opts);
     let sorted_pkgs = deps.sort();
     let mut outputs: Vec<(Package, PackageOpts<'_>, FileLock)> = Vec::new();
     for (pkg, cli_features) in sorted_pkgs {
@@ -233,7 +234,7 @@ fn do_package<'a>(
             to_package: ops::Packages::Default,
             ..opts.clone()
         };
-        let ar_files = prepare_archive(ws, &pkg, &opts)?;
+        let ar_files = prepare_archive(ws, &pkg, &opts, &mut vcs_info_builder)?;
 
         if opts.list {
             for ar_file in &ar_files {
@@ -368,6 +369,7 @@ fn prepare_archive(
     ws: &Workspace<'_>,
     pkg: &Package,
     opts: &PackageOpts<'_>,
+    vcs_info_builder: &mut vcs::VcsInfoBuilder<'_, '_>,
 ) -> CargoResult<Vec<ArchiveFile>> {
     let gctx = ws.gctx();
     let mut src = PathSource::new(pkg.root(), pkg.package_id().source_id(), gctx);
@@ -386,7 +388,7 @@ fn prepare_archive(
     let src_files = src.list_files(pkg)?;
 
     // Check (git) repository state, getting the current commit hash.
-    let vcs_info = vcs::check_repo_state(pkg, &src_files, gctx, &opts)?;
+    let vcs_info = vcs_info_builder.build(pkg, &src_files)?;
 
     build_ar_list(ws, pkg, src_files, vcs_info)
 }

src/cargo/ops/cargo_package/vcs.rs

@@ -9,6 +9,7 @@ use serde::Serialize;
 use tracing::debug;
 
 use crate::core::Package;
+use crate::core::Workspace;
 use crate::CargoResult;
 use crate::GlobalContext;
 
@@ -31,6 +32,28 @@ pub struct GitVcsInfo {
     dirty: bool,
 }
 
+/// A shared builder for generating [`VcsInfo`] for packages inside the same workspace.
+///
+/// This is aimed to cache duplicate works like file system or VCS info lookups.
+pub struct VcsInfoBuilder<'a, 'gctx> {
+    ws: &'a Workspace<'gctx>,
+    opts: &'a PackageOpts<'gctx>,
+}
+
+impl<'a, 'gctx> VcsInfoBuilder<'a, 'gctx> {
+    pub fn new(
+        ws: &'a Workspace<'gctx>,
+        opts: &'a PackageOpts<'gctx>,
+    ) -> VcsInfoBuilder<'a, 'gctx> {
+        VcsInfoBuilder { ws, opts }
+    }
+
+    /// Builds an [`VcsInfo`] for the given `pkg` and its associated `src_files`.
+    pub fn build(&mut self, pkg: &Package, src_files: &[PathBuf]) -> CargoResult<Option<VcsInfo>> {
+        check_repo_state(pkg, src_files, self.ws.gctx(), self.opts)
+    }
+}
+
 /// Checks if the package source is in a *git* DVCS repository.
 ///
 /// If *git*, and the source is *dirty* (e.g., has uncommitted changes),